Ref.: D Code: 00 MT BM 22 PLUS GB04

Transcription

1 OPERATING AND MAINTENANCE MANUAL Ref.: D Code: 00 MT BM 22 PLUS GB04 OLDHAM S.A. Plant and Head Office Zone Industrielle Est Rue Orfila - B. P ARRAS Cedex - FRANCE Tél : 33 (3) Fax : 33 (3) information@oldham.fr Maj : 13/11/02

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3 OLDHAM SA GAS AND FLAME DETECTION STACK GAS AND DUST MONITORING We thank you for choosing an OLDHAM SA instrument. We have taken every step to ensure that this equipment continues to give you complete satisfaction. Please read the instruction manual carefully before using the instrument. 3

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5 L I M I T S O F R E S P O N S I B I L I T Y * OLDHAM SA hereby rejects any and all responsibility with regard to any person for material damage, bodily injury or death resulting in whole or in part from the inappropriate use, installation or storage of its equipment not conforming to the instructions and to warnings and/or not conforming to standards and regulations in force. * OLDHAM SA does not allow or authorize any company, person or legal entity to assume such responsibility on the part of OLDHAM SA, even if involved in the sale of the products of OLDHAM SA. * OLDHAM SA shall not be liable for any direct or indirect damage, or any direct or indirect legally awarded damages resulting from the sale and use of any of its products, UNLESS THOSE PRODUCTS WERE SPECIFIED AND CHOSEN BY OLDHAM SA FOR THE USE MADE OF THEM. O W N E R S H I P C L A U S E S * Sketches, drawings, specifications and data included herein contain confidential information which is the property of OLDHAM SA. * These information shall not be, in part or in whole, physically, electronically or in any other form whatsoever, reproduced, copied, divulged, translated, used as a basis for the manufacture or sale of OLDHAM SA equipment or used for any other reason without the prior approval of OLDHAM SA. W A R N I N G S * This document is not a contractually binding document, OLDHAM SA reserves the right to make any changes, without notice, to the technical characteristics of its equipment in order to improve performance levels, in the interest of its customers. * CAREFULLY READ THE INSTRUCTIONS BEFORE ALL FIRST USE: This instruction manual must be read by any person who is, or will be, responsible for the use, maintenance or repair of this equipment. * This equipment will conform with the specified performance levels only if it is used, maintained and repaired in accordance with the directives of OLDHAM SA and by OLDHAM SA personnel or personnel authorized by OLDHAM SA. 5

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7 CONTENTS I. DESCRIPTION POWER SUPPLIES General power supply Recharging the battery unit Saving in memory MEASURING CELLS Explosimetric cell: Toxic gas and oxygen metering cells Catharometric cell Carbon dioxide cell REMOTE SAMPLING Manual system BM 22 Plus beacon fitted with a built-in electric pump The various probes USING THE BM 22 PLUS BEACON IN THE FIELD Positioning the appliance Beacon function II. UTILIZATION FUNCTIONS OF KEYPAD IN FIELD FUNCTIONS OF KEYPAD IN WORKSHOP READING OF MEASUREMENTS STARTING UP Starting up in standard mode Starting up with choice of reference explosive gas Starting up with auto-adjustment SHUTTING DOWN LIGHTING OF DISPLAY PANEL SCROLLING THROUGH PARAMETERS STORED IN MEMORY ALARMS "Gas" alarms LEL alarm (explosimetric) Oxygen alarm Toxic gas alarm Fault alarms Acknowledging alarms Acknowledging gas alarms Acknowledging fault alarms Transmission of alarms

8 8.5 Centralguard AC Example of interconnections MEASUREMENTS Display of instantaneous measurements In automatic operation With hand-operated or electric pumping systems Automatic switching to "0-100% GAS" range Memorizing histogram measurements Operating principle Output of histograms III. MAINTENANCE ACCESS TO MAINTENANCE (MENUS) PROGRAMMING MENU Case of an explosimetric cell Case of an oxygen metering cell Case of a toxic gas metering cell CALIBRATION MENU Calibrating an explosimetric cell Calibrating a toxic gas metering cell Calibrating an oxygen metering cell "REPLACE EXPLOSIMETRIC CELL" MENU "CHANGE DATA/TIME" MENU IV. CHARGERS DESCRIPTION RECHARGING THE BATTERY OPERATION V. ACCESSORIES VI. SPARE PARTS VII. TECHNICAL CHARACTERISTICS BEACON BM 22 PLUS CELLS (NON-EXHAUSTIVE LIST)

9 I. DESCRIPTION? The BM 22 Plus beacon is a portable gas detector. It can be used to detect the presence of four gases simultaneously in the air by means of measuring cells specific to each of the gases to be detected. These can be explosive or toxic gases or oxygen. Figure 1 : DESCRIPTION OF THE BM 22 PLUS 9

10 1. POWER SUPPLIES 1.1. General power supply The BM 22 Plus is supplied with power by a unit consisting of a set of rechargeable, interchangeable batteries. In normal operating conditions, the battery unit's running time varies according to the configuration (cells), (> 50 hours). The power supply unit contains a printed circuit and 2 x 3 elements, 1V2 / 1,700 mah. Item.1 FIGURE 2 : BM 22 Plus battery Recharging the battery unit - The rechargeable battery unit is recharged directly via a connector, item 1, Fig. 2. (See the section on CHARGERS) Saving in memory A second battery of the lithium type (nonrechargeable) is used to memorize the data specific to the BM 22 Plus beacon, particularly when the appliance is not in service (switched off) or when the battery unit is not installed (main power supply). This lithium battery has a maximum service life of 5 years. 10

11 Lithium battery IMPORTANT: This appliance is certified for utilization in explosive atmospheres in groups I and II and only when it is equipped with non-rechargeable or rechargeable batteries of a type recommended by the manufacturer. 2. MEASURING CELLS 2.1. Explosimetric cell: This cell detects explosive gases in the range of 0% to 100% LEL. It is fitted with an explosionproof cell body and filaments. It must be placed in the BM22 Plus as described hereinafter. 11

12 Toxic or oxygen cell unit If a catharometric cell is used: it is mandatory to position it in the last place with regard to the explosimetric cell (as in this case showing 4 cells) Mandatory positioning if a CO2 cell is used Figure 3 Explosimetric cell (mandatory position) Figure Toxic gas and oxygen metering cells These removable, interchangeable cell units are equipped with an electrochemical cell and electronic components including an EEPROM memory in which OLDHAM has stored the cell's specific characteristics (such as the measuring range, various correction factors, STEL and TLV alarms, serial number). Another item of data, known as the "wear rate" allows the BM 22 Plus to automatically determine the best time to change the cell. For this reason, cell units of this type are also known as "intelligent units". They are positioned as shown above (Fig. 3). 12

13 2.3. Catharometric cell This removable, interchangeable cell unit is used to detect explosive gases at high content levels within the range from 0% to 100% gas in air (by volume). This unit has the same characteristics as the electrochemical and oxygen units. It must be positioned in last place with regard to the explosimetric cell in position 2, 3 or 4 as applicable (as shown above in Fig. 3) Carbon dioxide cell This removable, interchangeable cell unit is equipped with a semiconductor type infrared detector for the detection of CO2 (carbon dioxide). This "intelligent unit" has the same characteristics as the other units (memory) and can be used for the range of from 0 to 5% CO2 in air. It must be positioned as shown above (Fig. 3). 3. REMOTE SAMPLING The BM 22 PLUS can be equipped with a sampling system for the measurement of gas concentrations either in locations that are normally inaccessible or before entry into premises liable to be polluted by gases (such as tanks, sewers and tunnels). 13

14 3.1. Manual system This kit is equipped with a hand-operated pumping bulb. Gas injection cap Sampling probe Hose Fitting of the hand-operated pumping kit on the BM22 Plus (1) Make sure that the pumping bulb is fitted the right way round (on the probe). CAUTION: Do not forget to remove the "injection cap" from the BM 22 PLUS when you have finished using the remote sampling system BM 22 Plus beacon fitted with a built-in electric pump? In this case, the beacon and the built-in pump are supplied with power from the same battery unit. Circuit and electric pump. 14

15 Utilization:? Connect the sampling system to the olive seal (item 1).? Position the gas input device, item 2, on the cell port.? The pump starts up automatically (magnetic switch).? After carrying out the sampling operations, remove the device. The pump stops automatically. Item 2 Item 1 Remark: When the pump is stopped, the beacon performs detection in normal NATURAL DIFFUSION mode (with the gas input device removed) The various probes The hand-operated and electric sampling systems can be fitted with various types of probe: Rigid probe Semi-rigid probe Telescopic probe 15

16 4. Using the BM 22 Plus beacon in the field 4.1. Positioning the appliance The person carrying the beacon has two possible courses of action:? to go about his or her work, leaving the BM 22 PLUS beacon to monitor the atmosphere,? to carry out spot checks using a sampling system (hand-operated or electric) Beacon function The BM 22 PLUS must be placed in the vertical position with the battery unit as the base. Depending on the type of gas to be detected or which may be present, the appliance must be placed:? on the ground, for the detection of heavy gases (H2S, CO),? at mid height (about 1 metre above the ground) or at the outlet of a ventilation port for the general detection of a maximum number of gases or for oxygen monitoring). II. UTILIZATION 1. FUNCTIONS OF KEYPAD IN FIELD? Appliance on and off switch? Gas audio alarm acknowledgement? Display panel back-lighting (automatically switched off after about 15 seconds)? Selection of menus during the operating phase On/Off Display panel back-lighting Menu scrolling Audio alarm acknowledgement or validation Selection of menus or modification of parameters Function of keys during field operation. 16

17 2. FUNCTIONS OF KEYPAD IN WORKSHOP Access to this level of programming is only possible after inserting the "programming sheet" or by opening the appliance. You can then use the keys on the BM 22 PLUS beacon to:? start up or shut down the appliance? validate an option proposed? move through a menu? select a menu. Key to move through a menu On/off key Key to validate proposed option Key to select menu options Key functions in programming mode. 3. READING OF MEASUREMENTS The gas content measured by each of the cells in service can be viewed on the alphanumeric display panel. This display panel is divided into four separate areas (quadrants), each one corresponding to a specific cell or channel. Data area Channel No. 1 Data area Channel No. 2 Data area Channel No. 3 Data area Channel No. 4 Quadrants displaying data specific to each of the four channels. A maximum of four measurements can be displayed simultaneously. However, as the quantity of data which may be useful to the user is too great to be displayed in each quadrant of the display panel, the measurements are displayed in cyclic mode, as follows (Fig. 4): 17

18 ? measurement - measuring unit,? measurement - gas symbol. The user therefore reads:? the measurement which is displayed in continuous mode,? the measuring unit which is displayed before the gas symbol. Example: The values representing the concentration of methane gas (0% LEL CH4), of CO (10 ppm CO), of NO2 (0.0 ppm NO2) and oxygen (20.9% O2) are clearly displayed. 0 LEL 10 ppm 0.0 ppm 20.9% 0 CH4 10 CO 0.0 NO O2 Figure 4 : Example of alternating display (measurement - type of gas) illustrating the sequence of data displayed after reading. 4. STARTING UP REMINDER: Before starting up the appliance by carrying out the various procedures described above, the beacon must be switched on by placing the general ON / OFF switch to the "ON" position. The cell cover must be removed in order to access this switch (Item 1). ON When the appliance is started up, you have the choice between the following three procedures:? the standard procedure adopted in most cases,? a procedure allowing the reference explosive gas to be selected, which is useful when checking for a specific gas (town gas, methane, etc.),? a procedure known as "auto-adjustment" which allows the automatic adjustment of the zero of explosimetric cells or toxic gas metering cells as well as the setting of the oxygen cell to 20.9%. This procedure must be regularly carried out. 18

19 4.1. Starting up in standard mode? Briefly press the "ON/OFF" key.:? The appliance runs a test phase for a few seconds and displays the message: Tests in progress? If the internal tests on the battery, cells and electronic components, etc., are satisfactory, the values measured by the cells are shown in the display panel. Example: 0 LEL 10 ppm 0.0 ppm 20.9% 0 CH4 10 CO 0.0 NO O2 The display of the gas symbols is replaced by the display of the measuring units (% or ppm) in cyclic mode as shown above.? If the tests are unsatisfactory, the appliance switches to alarm mode (discontinuous rapid audio signal, flashing of the common alarm indicator light and flashing of the indicator light for the relevant channel). See the section on "Alarms" for further details Starting up with choice of reference explosive gas Selecting the mode? Hold down the "Lighting" key.? Start up the appliance by pressing the "ON/OFF" key.? Release both keys? the following message is shown in the display panel for a few seconds: Tests in progress? Then the following display appears Type of gas: Methane LEL 19

20 Choosing the reference gas? Each time you press the key: a different reference gas is displayed. Thirty-one (31) reference gases have been preprogrammed in the 0-100% LEL range. The thirty-second (32) gas ("Other") can be selected by the user to define a specific gas. The data for that gas are entered in the workshop. The list displayed starts with the gas currently programmed.? To confirm your choice: when the selected gas is displayed press the "ENTER" key The display panel indicates "Test in progress" before switching to the working phase. The reference explosive gas will then be the gas that was previously selected.? To abort the procedure: press the "Lighting key" or press "ON/OFF" In this case, the reference gas that was programmed when the appliance was switched on is not modified. Note: If you do not validate any gas, the BM 22 PLUS beacon waits approximately 10 seconds and then switches to the test phase and to the normal scanning phase without changing the reference gas. This has the same effect as aborting the procedure.? If the tests are unsatisfactory, the appliance switches to alarm mode (discontinuous rapid audio signal and flashing of the alarm indicator light). The appliance is ready to use. See the next section. Example: 0 CH4 10 co 0.0 NO O2 0 EXP 10 CO 0.0 NO O2 Example of switching from a "% LEL CH4" range (high) to a "% LEL BUTANE" range (low) Starting up with auto-adjustment Selecting the mode? Make sure that the appliance is located in an area that is free from any trace of explosive or toxic gases and where the oxygen content level is normal (such as a ventilated area outdoors). 20

21 ? Hold down the "ENTER" key? Start up the appliance by pressing the "ON/OFF" key? Release the two areas. The display panel indicates: and then: Auto-adjustment requested Tests in progress Wait for stabilization before displaying the current measurement on each cell in operation. For example: 0 CH4 STOP STOP 20.9 O2? As soon as the measurements have stabilized, press "ENTER" When the auto-adjustment procedure has been successfully completed, the display panel indicates: Auto-adjustment done Auto-adjustment impossible If the ambient temperature is lower than -5 C or higher than +45 C or if the batteries are flat, the auto-adjustment procedure cannot be carried out. The display panel indicates: Auto-adjustment impossible 21

22 Auto-adjustment performed? Oxygen measurement is set to 20.9% but other measurements are automatically set to a value of zero: 0 LEL 0 ppm 0.0 ppm 20.9%? If the tests are unsatisfactory, the appliance switches to alarm mode (discontinuous rapid audio signal and flashing of the alarm indicator light). Otherwise, the appliance is ready to use. See the next section. Note: There is no time limit to the auto-adjustment procedure. It is up to the user to exit from this procedure. 5. SHUTTING DOWN The appliance is shut down by holding down the "ON/OFF" key for three seconds The following countdown appears on the display panel before it is switched off: Stop request 3 Stop request 2 Stop request 1 When the appliance is shut down, the memorized values (cell adjustment data, alarm thresholds, histogram, etc.) are not lost. These values are memorized for a theoretical period of between 3 and 5 years according to the service life of the lithium battery. On return to the workshop, it may be appropriate to carry out the recharging of batteries or the printing of exposure histograms. 22

23 6. LIGHTING OF DISPLAY PANEL It can be made easier to read measurements in dimly lit conditions by pressing the "Lighting" key This operates a back-lighting device which lights up the data on the display panel. This lighting is automatically switched off after 15 seconds. The lighting section can be used in hazardous environments, i.e. environments containing explosive gases: the BM 22 PLUS beacon complies with intrinsic safety requirements. 7. SCROLLING THROUGH PARAMETERS STORED IN MEMORY During normal operation of the appliance, you can consult data sequences regarding, on the one hand, gas measurements and, on the other hand, specific data internal to the appliance (battery voltage, date and time). These displays are selected by pressing the "Up" arrow key the required number of times The data memorized by the appliance are then displayed. Starting from the display of instantaneous measurements and in maximum configuration, the data displayed concerns: Date and time These data are displayed in the form "dd-mm-yy" (day-month-year) and "hh-mm-sec" (hoursminutes-seconds) Date : Time: 18 h03 Example of a display of date and time 23

24 Battery voltage This is expressed in volts and by bar graph Battery: 7.16 v * * * * * * When there is a gradual drop in voltage, the following message is displayed: "Recharge battery". If the voltage drops to below 6.4 V, the appliance is automatically de-energized. The display panel is switched off. Recharge battery Example of the display of battery voltage and warning message Min-Max General data specific to each channel (measuring unit, type of gas and minimum and maximum values) are then displayed. Press key to display the data for each channel in service. Channel 1: Min 1 MAX EXP LEL 15 Channel 2: Min 0 ppm CO Max 8 Channel 3: Min 0 ppm H2S Max 2 The data can be viewed by repeatedly pressing the key: 24

25 STEL and TLV This information, which is programmed by the manufacturer and stored in the internal read-only memory of the measuring cell, is available when at least one toxic gas metering cell is connected and in service ("ON" function).? The STEL (Short Term Exposure Limit) data specific to each toxic gas metering channel (STEL symbol, type of gas, measurement and measuring unit) are displayed, in turn, when you repeatedly press the "UP" arrow key: Then, when you press this key again, the next channel in service is displayed. The STEL values can only be displayed when the appliance has been operating for at least two minutes.? The TLV (Time Limit Value) data specific to each toxic gas metering channel (TLV symbol, type of gas, measurement and measuring unit) are then displayed, in turn, when you repeatedly press the "Up" arrow key: Then, when you press this key again, the next channel in service is displayed. In the same way as above, the TLV values can only be displayed when the appliance has been operating for at least two minutes. Channel 2: STEL CO 15 ppm STEL data are displayed successively. The procedure is the same for Min/Max. Return to user menu The user menu reappears immediately after the last data item in the display of STEL/TLV measurements (BM 22 PLUS beacon fitted with at least one toxic gas metering cell) or, in other cases, of Min/Max data. After pressing the key, you can return to the display of instantaneous measurements in the following ways:? immediately, by pressing the Lighting key? automatically, after a period of 30 seconds. Note: Other displays are available using this procedure but these can only be obtained by connecting the appliance to a printer or computer. 25

26 8. ALARMS The alarms given are of the visual type (indicator lights and display panel) and the audio type. Indicator light: explosimetric measuring range exceeded Channel No. 1 explosimetric alarm indicator light Channel No. 3 alarm indicator light Channel No. 2 explosimetric alarm indicator light Channel No. 4 alarm indicator light Alarm indicator lights "Gas" alarms Depending on the programming and the type of gas, "gas alarms" may be triggered when the following values are exceeded:? instantaneous (on all four channels),? minimum (applicable on the oxygen metering channel only),? maximum (on all four channels),? Short Term Exposure Limit (STEL) corresponding to a sliding mean over 15 minutes on each channel equipped with a toxic gas metering cell,? Time Limit Value (TLV) corresponding to a sliding mean over 8 hours on each channel equipped with a toxic gas metering cell. In this way, as soon as the predefined alarm thresholds are exceeded on at least one channel, the BM 22 PLUS beacon emits a strident and extremely powerful, cyclic audio signal. At the same time, the indicator light for the relevant channel flashes and the alarm message or messages (FAULT, ALARM, TLV, STEL, min., etc.) appear on the display panel along with the value measured in the relevant area. FAULT AL TLV 0.0 ppm 20.9% Example of the display of a fault and an TLV alarm 26

27 LEL alarm (explosimetric) BM 22 PLUS beacon without oxygen metering cell or "Remove doubt" option? Proceed with caution (presence of explosive gases).? Press "ENTER" to acknowledge the audio alarm and reactivate the display. BM 22 PLUS beacon with oxygen metering cell and "Remove doubt" option? Proceed with caution (presence of explosive gases).? Press "ENTER" in order to: - try to acknowledge the audio alarm. (Acknowledgement is possible if the measurement is less than 10% LEL). - and reactivate the display. Display of explosimetric measurement Alarm indicator lights for range 0-100% GAS 0-100% LEL Buzzer acknowledge key Information given in case of an explosimetric alarm. 27

28 Oxygen alarm The oxygen measurement must be between the two oxygen thresholds: excess oxygen and insufficient oxygen. The alarm is triggered as soon as the measurement fails to fall within the "High alarm/low alarm" window.? Leave the area as quickly as possible. Excessive oxygen content and insufficient oxygen content are both hazardous.? Press "ENTER" to acknowledge the audio alarm and reactivate the display. Display of oxygen measurement Buzzer acknowledge key Channel alarm indicator lights Information given in case of an oxygen metering alarm Toxic gas alarm A "toxic" alarm can be triggered by three types of measurement:? measurement exceeding the maximum authorized instantaneous value? measurement exceeding the authorized Time Limit Value (TLV),? measurement exceeding the authorized Short Term Exposure Limit (STEL). In each of these cases, the measurement of the channel concerned is replaced by a specific message in cyclic mode:? "ALARM" when the permitted maximum instantaneous value has been exceeded. The measurement is frozen so that the user can read off the maximum value recorded. 28

29 Display of toxic gas metering measurement Channel alarm indicator lights Buzzer acknowledge key Information given in case of a toxic gas metering alarm.? "STEL AL" when the Short Term Exposure Limit has been exceeded (sliding mean for 15 minutes)? "TLV AL" when the Time Limit Value has been exceeded (sliding mean for 8 hours). Proceed as follows:? Leave the area as quickly as possible. Excessive instantaneous or accumulated content levels (STEL or TLV) are equally dangerous.? Press "ENTER" to acknowledge the audio alarm and reactivate the display Fault alarms Faults can be divided into two groups:? Faults regarding cells (outside range, worn cell, request for calibration on occurrence of a major deviation during auto-adjustment): these faults lead to the generation of individual messages displayed on the relevant quadrant of the display panel and the triggering of a cyclic visual and audio alarm. 29

30 ? Fault regarding the appliance itself (flat batteries or electronic fault): The corresponding fault message appears on the display panel. This message takes priority over all other messages concerning the cells. OUTSIDE RANGE FAULT 0.0 NO O2 Flat battery Examples of information that may be displayed for the user. Actions "Flat batteries" Proceed with the charging of the batteries. The running time is approximately 20 minutes after which the appliance stops automatically. This alarm cannot be acknowledged, i.e. pressing on the "ENTER" tactile area has no effect. "> 100 LEL"? This concerns the explosimetric channel only.? In this case: - the display of the relevant quadrant is locked, - it is impossible to acknowledge the continuous audio signal, - the alarm indicator light for the relevant explosimetric channel and the general alarm indicator light are illuminated in steady mode.? The BM 22 PLUS beacon must be shut down and then started up again in order to restore normal operating conditions.? Proceed with caution in the relevant area owing to the presence of explosive gases with a content level higher than LEL. Note: This alarm is only triggered if the "0-100% GAS" option has not been selected. If the BM22 PLUS is equipped with this option and if it is also equipped with an oxygen metering cell or a katharometric cell, measurement switches directly to the "0-100% GAS" range. "Over range"? This only concerns toxic gas metering channels.? In this case: - it is impossible to acknowledge the continuous audio signal, - the alarm indicator light for the relevant toxic gas metering channel and the general alarm indicator light are illuminated in steady mode, - leave the area immediately owing to the presence of toxic gases at an excessively high content level. 30

31 " New cal "? Automatic zero adjustment is impossible owing to, for example, an excessively great drift in the cell zero.? Proceed with the replacement of the cell concerned. Buzzer acknowledge key (audio alarm) Audio alarm acknowledge button 8.3. Acknowledging alarms Acknowledging gas alarms This does not cancel the gas alarm but only the rapid audio signal. When the tactile "ENTER/Buzzer" area has been pressed, the rapid audio alarm is deactivated but the corresponding alarm indicator light continues to flash until the measurement falls to below the programmed alarm threshold. As soon as the measurement returns to within the defined limits, the visual signal is extinguished automatically Acknowledging fault alarms This happens automatically as soon as the measurement on the relevant channel returns to within the limits defined by the alarm thresholds. This is applicable for instantaneous alarms as well as for mean exposure values (TLV) or limit exposure values (STEL). 31

32 8.4 Transmission of alarms In the case where alarms are triggered (as already described in Chapter 8), the BM 22 PLUS beacon also controls a "positive safety alarm transmission" module (static relay, electronic components). When ordering your appliance, you should specify whether you wish to control an external system supplied with "AC" or "DC" power. USING THE RELAY OUTPUT AL + or AL - Control output (relay) AL or AL - * * IMPORTANT: Parameters to be complied with (1) AC DC I max 150 ma - V max 50 V I max 150 ma - V max 75 V Caution: If the BM 22 Plus beacon is used in an explosive atmosphere, the parameters are modified as the operation of the contact must not adversely affect the intrinsic safety of the beacon. (Users who connect up an external circuit unknown to Oldham shall be solely responsible for any consequences). The parameters are specified in the certificate of compliance.? Apparent characteristics as seen from the relay output: V = 0 I = 0 Ceq = 0 Leq = 0? Characteristics of the external circuit that may be connected to the relay: V Max = 50 V I max = 100 ma 32

33 8.5 Centralguard AC 22? The "Centralguard AC 22" is a beacon which centralizes alarms originating from a number of "BM 22" beacons (maximum of 4). Carrying handle Light flashing device Common relay output (item 1) Audio "screech" device Start-up indicator light (1) Item 3 Alarm indicator light (1) Battery fault indicator light Inputs for alarms entering "BM 22" (max. 4) (item 3) Item 1 Power ON indicator light Battery unit Figure 4 On/Off Charger connector (item 2) (1) There is one start-up and alarm light per channel (maximum of 4).? The AC 22 beacon is equipped with a battery unit, an audio warning device and a light flash device identical to those of the BM 22 beacon.? To recharge the battery unit, the same charger is used as for the BM 22 beacon (CR 22), (item 2 6 Fig. 4).? The AC 22 beacon is equipped with four alarm inputs (item 3 - Fig. 4), for the centralization of alarms from BM 22 beacons, and a common relay output (item 1 - Fig. 4) identical to that of the BM 22 beacon. 33

34 8.5.1 Example of interconnections MULTIGUARD BM 22 CENTRALGUARD AC 22 TRIPOD FOR BM 22 AND AC 22 EQUIPPED REEL EM MEASUREMENTS 9.1. Display of instantaneous measurements In automatic operation All the instantaneous measurements concerning gases are displayed in continuous mode. The display panel is divided into four separate areas (quadrants), each one corresponding to a specific cell or channel Quadrant No. 1 Channel No. 2 Quadrant No. 2 Channel No. 2 0 LEL 10 ppm 0.0 ppm 20.9% Quadrant No. 3 Channel No. 3 Quadrant No. 4 Channel No. 4 The four areas for the display of messages 34

35 As the quantity of information to be displayed is greater than the capacity of each quadrant of the display panel, measurements are displayed in cyclic mode, as follows:? measurement - measuring unit? measurement - gas symbol The user therefore reads:? the measurement which is displayed in continuous mode,? the measuring unit which is displayed before the gas symbol. Example: 0 LEL 10 ppm 0.0 ppm 20.9% 0 CH4 10 CO 0.0 NO With hand-operated or electric pumping systems? Using the pumping handle, pump at least four times to engage the alarm and about eight times for reading the measurement.? Wait for the measurements to stabilize before confirming them. The measurements will be either overestimated (in the case of explosive gases) or under estimated (in the case of oxygen) during pumping owing to the movement of air.? On the electric pump, press the On/Off button and wait a few seconds (10) before reading the measurement. Any fault affecting the pumping system will be indicated by the audio alarm and on the display panel with the following message. PUMP OUTPUT INSUFFICIENT 9.2. Automatic switching to "0-100% GAS" range An option allows automatic switching from the measurement of explosive gases in the "0-100% LEL" range to the "0-100% GAS" range when the measurement is higher than 100% LEL for the selected reference gas. However, this measurement can only be made using an appliance equipped with an "explosive gas" cell and an "oxygen" cell or a katharometric cell. 35

36 In this case, the orange "Remove doubt" indicator light comes on and the measurement is displayed in cyclic mode, as follows: 25% 0 ppm 0.0 ppm 15.6% 25 GAS 0 CO 0.0 NO O2 For channel 1, the display limit shows the "%" sign and the word "GAS" aletrnately. The "Eliminate doubt" indicator light is illuminated. ON/OFF key "Eliminate doubt" indicator light Key to move through menu Key to select from a menu Key to validate proposed choice Position of the orange "Eliminate doubt" indicator light Memorizing histogram measurements Depending on the version, the BM 22 PLUS beacon can memorize measurements so that they can be output subsequently on a printer, on a MINITEL videotex screen or on a computer in the form of histograms. The "Histograms" function allows values and events memorized by the BM 22 PLUS beacon during operation to be output on a printer or a PC type computer (such as a workstation). The data contained in the histogram memory can only be reset during the printout procedure. Switching off the BM 22 PLUS beacon has no effect on the storage of data in memory. 36

37 Operating principle The operating principle of the storage of data in memory has to be understood in order to make best use of the data output when histograms are printed. Memorized items The BM 22 PLUS beacon stores groups of data when it is started up and then on a cyclic basis. Each of these groups has the same structure and contains:? the mean measurement of concentrations on each sensor in service over a period of one minute (one sampling operation per second),? the events on each channel: - resetting - fault - instantaneous or mean alarms - types of maintenance requested (programming, calibration, replacement of cell) - date and time - the discharged condition of the battery - request for auto-adjustment - request for the maintenance function. Memory storage capacity As the physical memory of the BM 22 PLUS beacon is limited, the number of measurements is also limited and, therefore, so are operating times. We can allow for a recording capacity of 48 hours with 8 events per channel and per 24 hours. If the number of data items to be stored exceeds the storage capacity of the BM 22 PLUS beacon, the oldest data items are lost (FIFO procedure: first data item in, first data item out). To put it simply, the memory freed is used to store new data. Readable items The appliance gives a mean value over a period of one minute for each channel in service and every second. These average data items are stored in memory. However, when connected to the serial port of the BM 22 PLUS beacon:? A PC type computer can be used to read the mean values of measurements per minute.? A serial printer, however, will only read the data for the mean value every quarter of an hour. In other words, a printed measurement will give the mean value of measurements over a period of 1/4 hour, with the new mean being calculated by the BM 22 PLUS beacon when printing is performed. 37

38 Data storage period The data stored by the BM 22 PLUS beacon are memorized even if the appliance is not used for a long period (out of service). The storage period is between 3 and 5 years, depending on the lithium battery. Resetting of histograms This is done by means of an explicit request on the display panel when printing out memorized data. RESET tables? Yes: ENTER, No: Display of the request for resetting of histograms after a print request Output of histograms The "Histograms" function is used to output values and events memorized by the BM 22 PLUS beacon on the printer or a PC type computer. Data are memorized during normal operation of the appliance. The data contained in the histograms memory can only be reset during the printing procedure. 38

39 Connection to a printer Reminder The printer must be PC compatible and equipped with an RS 232C interface configured as follows:? 9,600 bauds? 8 bits? even parity? 1 stop bit? XON/OFF protocol. The connecting cable is supplied with the BM 22 PLUS beacon on request. Connections? Connect the DIN connector on the connecting cable to the BM 22 PLUS beacon.? Connect the 25-pin cable to the serial port on the printer.? Check the configuration of the printer switches and position the switches on its front face to "ON" and "ON LINE". See the printer manual. Item 1 Figure 6: Connecting the BM 22 PLUS beacon to a serial printer. Connection to a parallel printer requires the fitting of a serial-to-parallel converter. Connection to a PC compatible computer This requires the utilization of a software package called COM 21.W. See the manual for that software. 39

40 Output of histograms Reminder Histograms can only be output when the BM 22 PLUS beacon has been in operation for at least:? A quarter of an hour for output on a printer,? One minute for output on a PC compatible computer. Choice of printing procedure? Connect the cord linking the BM 22 PLUS beacon to the printer or to the computer, if this has not already been done.? Start up the BM 22 PLUS beacon by pressing the ON/OFF key? Press and release the "Up" arrow key until the following menu is displayed: Print: Quit: ENTER? The printing procedure is started by pressing "Enter".? When you press on any other key, you return to the operating menu without making any modification. Output This concerns both the BM 22 PLUS beacon connected to a serial printer and the BM 22 PLUS beacon connected to the serial port of a PC compatible computer. On output, one of two types of display is automatically selected by the BM 22 PLUS beacon.? If the data memorization period has been less than 15 minutes, the data are set out in the form of tables.? If the memorization period has been at least 16 minutes, the data are set out in graph form. 40

41 Optimal resetting of data memory At the end of the printing procedure, the display panel indicates: RESET tables? Yes: ENTER NO: You then have the choice between the two following options:? Cancelling the data still in memory (memory reset) and which has just been viewed, in order to restart the BM 22 PLUS beacon. This choice is made by pressing the "ENTER" key? Keeping the data and restarting the BM 22 PLUS beacon. This choice is made by pressing any key other than the "ON/OFF" key Return to normal mode This happens automatically when you have pressed a key as in the procedure described above. III. MAINTENANCE IMPORTANT : As the BM 22 PLUS beacon is a safety appliance, it must be calibrated at least twice a year and according to the operating conditions. These calibration operations, described in this chapter, are to be carried out by authorized, qualified personnel as they may adversely affect detection safety. 41

42 1. ACCESS TO MAINTENANCE (MENUS) When the appliance is operating, you can access this main menu in one of the two following manners.? After opening the housing (on the side without the cell openings) and positioning the switch towards the centre of the appliance. (1) Maintenance switch (1)? Pointer positioned to the left: measurement? Pointer positioned to the right: maintenance Without opening the housing, and after inserting the special plug in the DIN connector located on the side of the housing. DIN connector 42

43 These details are given for information only. It is advisable to follow the instructions given in each chapter dealing with maintenance. Indeed, it is sometimes preferable not to open the appliance and so avoid any incorrect handling of certain adjusting components. As soon as one of the two operations described above has been carried out, the display panel shows the message "Program a channel" indicating that the main maintenance menu is being opened. Note: The main menu cannot be accessed if the batteries are flat. Warning of this is given by a display of the message "Maintenance impossible". You can continue, however, by connecting up the mains power supply unit or by replacing the battery. As soon as the maintenance menu has been selected (connector or switch), the first of the four menus available appears on the display panel. This menu is "Program a channel". The other three menus are:? Calibrate a channel? Replace explosimetric cell? Manage date and time. Each time you press the "Up" arrow key the next menu is displayed in loop mode. You select a menu, i.e. enter the desired menu, by pressing the "ENTER" key 43

44 Program a channel Programming menu Calibrate a channel Calibration menu Replace explo. cell Explo. cell replacement menu Manage date and time Date and time menu Block diagram of main menu "Program a channel" menu This menu is used to:? Select the channel to be programmed.? Start up (On) or shut down (Off) the selected channel.? Inform the operator of the type of cell in the measuring range.? In the case of an explosimetric cell: select the type of reference gas from among the 31 preselected gases or enter the coefficient for a 32nd gas.? In the case of an oxygen metering cell, program the "min." and "max." alarm thresholds. 44

45 "Calibrate a channel" menu This menu is used to:? Select the channel to be calibrated.? Calibrate the zero and the sensitivity of cells with a standard gas. The oxygen cell, however, only requires adjustment of its sensitivity in pure air. Replace explo. cell menu This menu is used to:? Select the "explo." channel.? Adjust the zero and the sensitivity of the explosimetric cell by means of a standard mixture (methane). Note: There is no menu for the other cells which are calibrated in the factory. The data specific to each of these cells are stored in a memory contained in the cell unit. "Manage date and time" menu This menu is used to update the internal calendar and clock of the BM 22 PLUS beacon. These data are used to define time scales, especially when the measurements stored in memory (min., max., STEL, TLV) are printed out or downloaded to an external microcomputer. 2. PROGRAMMING MENU Carry out the maintenance access procedure (see III 1). Select the Programming menu.? "Program a channel" appears on the display panel.? Press the "ENTER" key Select the channel to be programmed. The display panel indicates: Select channel: 1 Channel 1 must correspond to an explosimetric cell. 45

46 The other channels (2, 3 and 4) can be allocated to either oxygen metering cell or a toxic gas metering cell.? Press the 'Up" arrow key to increment the channel number and select a channel other than channel number 1.? When reaching the desired channel number, press the "ENTER" key to confirm your choice. Selecting the channel status A channel can be activated (On) or deactivated (Off). When a channel is "On", gas measurement can be performed with the channel's cell. Proceed as follows: Each time you press the "Up" arrow key Press this key to select the channel status. the display switches between "On" and "Off". If you select "Off" for the channel concerned, proceed as described in the section on "Validating data entries". If you select "On", continue with the programming procedure as described in the next section. Channel: 1 On Channel: 1 Off Switching a channel on or off with the arrow key. 46

47 2.1. Case of an explosimetric cell Selecting the type of gas Thirty-one (31) preprogrammed explosive gases can be displayed immediately and another gas described as "other" can be assigned a multiplying coefficient specifically defined by the user. Proceed as follows:? Press the "Up" arrow key to select a gas from the list of 31 gases (see Table 1).? If the gas chosen is not named ""Other", press the "ENTER" key to confirm your choice. Then continue directly with the procedure described in the section on "Adjusting the alarm threshold". Gas Empirical formula LEL UEL Vapour density Coefficient /CH 4 Ethyl acetate C4H8O2 2.1 % 11.5 % Acetone C3H6O 2.15 % 13 % Acetylene C2H2 1.5 % 100 % Butane C4H % 8.5 % , 3 - Butadiene C4H6 1.4 % 16.3 % Butanone C4H8O 1.8 % 11.5 % Dimethyl ether C2H6O 3.0 % 27.0 % Ethanol C2H6O 3.3 % 19.0 % Ethylene C2H4 2.7 % 34.0 % Natural gas CH4 5.0 % 15.0 % Hexane C6H % 7.4 % Hydrogene H2 4.0 % 75.6 % Isobutane C4H % ~15 % Isopropanol C3H8O 2.15 % 13.5 % Methane CH4 5.0 % 15.0 % Ethylene oxide C2H4O 2.6 % 100 % Propylene oxide C3H6O 2.3 %? Pentane C5H % 8.0 % Propane C3H8 2.0 % 9.5 % Propylene C3H6 2.0 % 11.7 % Super SP95 Mixture 1.1 % ~ 6 % 3 à Toluene C7H8 1.2 % 7.0 % Xylene C8H % 7.6 % Diesel Oil Mixture 0.6 % ~ 6.0 % > Methanol CH3OH 5.5 % 44.0 % Kerosene (JP4) C % 5.0 % > Octane C8H % 6.0 % Table 1: List of main preprogrammed gases. The coefficients are defined with respect to methane. 47

48 ? If the gas chosen is named "Other", a multiplying coefficient must be entered. (See Table 2). Table 2 contains the coefficient for gases whose coefficients are not programmed in the appliance on a standard basis. These coefficients, which are to be programmed on the "Other gases" channel, are calculated with respect to methane as the appliance systematically recalculates the values of sensitivity coefficients with reference to methane gas. PLUS. Table 2: Additional sensitivity coefficients to be programmed on the "other gases " channel of the BM 22 Plus beacon Gas Empirical formula LEL UEL Vapour density Coefficient /CH4 Benzene C6H6 1.2 % 8.0 % Cyclohexanone (CH2)5CO 1.3 % 9.4 % High-oxtane Mixture 1.3 % 6.0 % > petrol (gasoline) Ethane C2H6 3.0 % 15.5 % LPG Prop+But 1.65 % ~9.0 % Methylamine CH3NH2 4.9 % 20.7 % Styrene C8H % 8.0 % White spirit Mixture 1.1 % 6.5 % > Example of utilization: Detection of white spirit with BM 22 PLUS: Select "Other gas" on the explosimetric channe. Program the coefficient = 3.0. Choose the standard gas. If it is white spirit, select "Other" as the standard gas. Calibrate the appliance in the normal way, specifying the content level of the standard gas used. Proceed as follows: - The following message is displayed: Other coeff: Select the unit for the coefficient to be displayed by repeatedly pressing the "Up" arrow key - When the desired figure is displayed press the "Right" arrow key - Select the tenths by repeatedly pressing the "Up" arrow key When the desired figure is displayed, press the "Right" arrow key 48

49 - Select the hundredths by repeatedly pressing the "Up" arrow key When the desired figure is displayed, press "ENTER" The whole coefficient is stored in memory. The permitted maximum values for this coefficient are between 0.50 and 9.99.? Adjusting the alarm threshold For all explosive gases except for "methane" - (Range 0 to 5%) - The message displayed may be as follows, for example: Explo. alarm 20 LEL CH4 Proceed as follows to modify the alarm threshold. The permitted alarm values are between 0 and 60% LEL. - Select the tens by repeatedly pressing the "Up" arrow key When the desired value is displayed, press the "Right" arrow key? Select the units by repeatedly pressing the "Up" arrow key. When the desired value is displayed, press "ENTER". For methane - Range 0 to 5% only - The following message may be displayed, for example: Explo. alarm 1.1% CH4 Proceed as follows to modify the alarm threshold. The permitted alarm values are between 0 and 3.0% CH4: Select the tenths by repeatedly pressing the "Up" arrow key 49

50 When the desired value is displayed, press "ENTER" Select the tenths by repeatedly pressing the "Up" arrow key When the desired value is displayed, press "ENTER" Proceed with final validation. (See the end of Chapter 2) Case of an oxygen metering cell The display panel indicates: Type of gas: oxygen? Press the "ENTER" key to display: Measuring range 30.0% O2 When you have pressed the "ENTER" key continue with the procedure described in the section on "Adjusting the alarm threshold". The memories in the cell unit are programmed in the factory with the cell s characteristic values. These data cannot be modified by the user. In this way, the BM 22 PLUS beacon automatically recognizes the type of cell connected to it.? Adjusting the alarm threshold There are two alarm values to be programmed: the upper limit and the lower limit.? The maximum permissible high alarm value is the value at the top of the cell measuring scale.? The minimum permissible low alarm value is the value at the bottom of the cell measuring scale. The maximum low alarm value is the value at the top cell measuring scale. Entering the high alarm value The appliance may display the following message, for example: High alarm 25.0% 02 50

51 ? If you press the "ENTER" key, this confirms the value displayed. Then continue with the section on "Validating data entries".? If you press the "Up" arrow key, this restores the alarm value to "00.0% O2".? When you press the "Up" arrow key, you can modify the alarm value displayed as follows: - Select the tens by repeatedly pressing the "Up" arrow key. When the desired figure is displayed, press the "Right" arrow key - Select the units by repeatedly pressing the "Up" arrow key. When the desired figure is displayed, press the "Right" arrow key - Select the tenths by repeatedly pressing the "Up" arrow key When the desired figure is displayed, press "ENTER" This has the effect of starting the procedure for entry of the low alarm value. Entering the low alarm value Carry out the same procedure as that described in the paragraph on "Entering the high alarm value". Press the "ENTER" key Continue with the following section.? Proceed with final validation. (See the end of Chapter 2). 51

52 2.3. Case of a toxic gas metering cell The display panel may show the following message, for example: Type of gas: Carbon monoxide? If you press the "ENTER" key, the following display appears: Measuring range 1000 ppm CO? When you have pressed the "ENTER" key, continue with the procedure described in the section following "ALARMS". The memories in the cell unit are programmed in the factory with the cell s characteristic values. These data cannot be modified by the user. In this way, the BM 22 PLUS beacon automatically recognizes the type of cell connected to it. Adjusting the alarm threshold There is only one alarm value to be programmed. The appliance may indicate, for example: Alarm 0030 ppm co? If you press the "ENTER" key, this confirms the value displayed. Then continue with the section on "Validating data entries".? If you press the "Up" arrow key, this restores the alarm value to "0000 ppm".? When you press the "Up" arrow key you can modify the alarm value displayed as follows: - Select the value of the first figure on the left by repeatedly pressing the "Up" arrow key 52

53 - When the desired figure is displayed, press the "Right" arrow key Repeat the same procedure until you reach the figure furthest right. When the desired figure is displayed, press "ENTER" alarm value.. This has the effect of starting the procedure for entry of the low Note: The number of figures making up the alarm value depends on the type of cell. This alarm value can therefore be between 1,000 ppm and 0.1 ppm. - Proceed with final validation (See the end of Chapter 2). Validating data entries The data have been stored in memory by the BM 22 PLUS beacon and have not yet been validated, i.e. confirmed. They are confirmed by means of the following procedure. The following message is displayed: Validate? Yes: ENTER No: You then return to main menu and:? The data previously entered is memorized when you press the "ENTER" key The data previously entered is lost and the initial values stored in memory before starting this procedure are preserved if you press any key other than "ENTER" Return to user mode? Remove the programming connector.? The BM 22 PLUS beacon is ready to use. 3. CALIBRATION MENU This menu is used for preventive maintenance (at least every six months) after replacing a cell or after the display of the message "OUTSIDE RANGE" indicating an excessive drift on measurement. This menu is used to:? Select the channel to be calibrated. 53

54 ? Automatically adjust the zero and sensitivity of the selected cell with a cylinder of standard gas and without using a screwdriver. In the case of the oxygen cell, however, the sensitivity is adjusted in pure air. General It is possible to calibrate a channel that is not equipped with a cell. When the erroneous data entries are validated, the message "Maintenance impossible" appears on the display panel.? Carry out the maintenance access procedure (See III 1). Selecting the "Calibration" menu? The display on the display panel is: Program a channel? Press the "Up" arrow key once. The display panel indicates: Calibrate a channel? Validate your choice by pressing the "ENTER" key. The display panel indicates: Select the channel: 1 Selecting the channel to be calibrated A specific channel corresponds to a specific measuring cell. Channel No.1 is mandatorily linked to an explosimetric cell:? To change the channel number, press the "Up" arrow key. 54

55 ? To confirm your choice and proceed with the calibration of the channel displayed, press the "ENTER" key Continue as described in the paragraph dealing with the cell concerned. 3.1 Calibrating an explosimetric cell Equipment required? Injection cap? A flexible vinyl tube, approximately 1 metre long,? A cylinder of standard gas with known content level (2% methane, for example) Preparing the BM 22 Plus beacon? Fit the injection cap of the BM 22 Plus beacon.? Connect the cylinder of standard gas to the injection cap with the flexible vinyl tube.? If the channel has not already been selected, see the section on "Selection the channel to be calibrated". Cylinder of standard gas Injection cap Vinyl tube Pressure gauge and pressurereducing valve Items necessary for the calibration of an explosimetric cell. Entering the value of the standard gas 55

56 This procedure defines the content level of the standard gas which will be injected into the explosimetric cell for the calibrating operation. The maximum permissible content level will be lower than 5.00% CH4. The display panel now indicates: Standard gas 1.00% CH4 To modify the value displayed:? Select the units by repeatedly pressing the "Up" arrow key When the desired figure is displayed, press the "Right" arrow key? Select the tenths by repeatedly pressing the "Up" arrow key When the desired figure is displayed, press the "Right" arrow key? Select the hundredths by repeatedly pressing the "Up" arrow key You can return to the units or tenths by pressing the "Right" arrow key When you have finished entering the value of the standard gas, press "ENTER". The value of the standard gas to be injected is stored in memory. Adjusting the zero This operation must be carried out in an environment that is not contaminated by gases. The display on the display panel may be, for example: MEASUREMENT of Zero -0.12% CH4? Press the "ENTER" key. The zero will be automatically corrected by the electronic components of the BM 22 Plus beacon during subsequent internal calculations. 56

57 Adjusting the sensitivity The display panel still shows the offset value obtained during the zero calibration phase. For example: Sensitivity -0.12% CH4 This value must be given as % CH4.? Inject the standard gas. The flow must be only just audible. The measured value of this flow rate is approximately 60 litres per hour.? As soon as the measurement has stabilized, press "ENTER". The display panel indicates: Validate? Yes: ENTER No:? If you press: - "ENTER", this confirms the measurement and you automatically return to the "Calibrating a channel" starting menu unless a problem occurs. (See the section on Problems). You can then calibrate another channel by pressing the "ENTER" key. It should be noted that the channel number is incremented automatically. If no other cell is to be calibrated, continue with the procedure described in the section on "Return to user mode".autre cellule n'est à calibrer, poursuivre au paragraphe 'Retour au mode Utilisateur' If you press any other key, you return to the "Calibrating a channel" starting menu without saving the values entered during the calibration procedure you have just carried out. Problems When you press the "ENTER" key panel may indicate: after the sensitivity has been measured, the display? "Zero offset too great": Check the local atmosphere (for presence of gas) and repeat the calibration. If the problem persists, replace the cell.? "Scale exceeded": when there is a discrepancy between the value of the injected standard gas and the programmed value, as in the section on "Entering the value of the standard gas". In this case, start the whole calibration procedure over again. If the problem persists, replace the cell. 57

58 "Worn" cell: possible discrepancy between the value of the injected standard gas and the programmed value, as in the section on "Entering the value of the standard gas", or attempt to calibrate without injecting any standard gas. Carry out the whole calibration procedure over again. If the problem persists, replace the cell. 3.2 Calibrating a toxic gas metering cell Carry out the same procedure as that used for the explosimetric cell (see III 3.1) but inject the toxic gas corresponding to the cell to be calibrated. The value of the standard gas will be equal to at least 30% of the measuring scale. 3.3 Calibrating an oxygen metering cell Equipment required? None. Preparing the BM 22 Plus beacon? The injection cap of the BM 22 Plus beacon must not be fitted.? If the "Oxygen" channel has not already been selected, see the section on "Selecting the channel to be calibrated".? Make sure that the surrounding atmosphere is clean and pure. (NORMAL OXYGEN content = 20.9%) Adjusting the sensitivity The display panel shows a value such as: Sensitivity 20.6% 02? As soon as the measurement has stabilized, press "ENTER". The BM 22 Plus beacon will subsequently adjust the oxygen measurement to 20.9% O2. The display panel indicates: Validate? Yes: ENTER NO:? When you press "ENTER", you automatically return to the starting menu ("Calibrating a channel"). You can calibrate another channel by pressing the "ENTER" key It should be noted that the channel number is incremented automatically. 58

59 If no other cell is to be calibrated, continue as described in the section on "Return to user mode".? Return to USER mode Remove the programming connector. The BM 22 Plus beacon is ready to use. 4. "REPLACE EXPLOSIMETRIC CELL" MENU This submenu is used to configure the BM 22 Plus beacon after installing a new explosimetric cell. It is also used to adjust the zero and the sensitivity of the explosimetric cell with a standard mixture (methane). This procedure must never be started without fitting the required cylinder of standard gas. REMINDER: Never connect or disconnect the explosimetric cell without first switching off the BM 22 Plus beacon. Equipment required? A Phillips screwdriver? A new explosimetric cell? Injection cap? A flexible vinyl tube, approximately 1 metre long? A cylinder of standard gas with known content level (2% methane, for example)? A screwdriver (tool kit). Replacing the explosimetric measuring cell? Remove the old explosimetric cell.? Fit the new explosimetric cell. A groove prevents any incorrect fitting.? Close the side of the housing protecting the cells. Selecting the maintenance menu With the appliance in operation, position the switch towards the centre of the appliance or insert the plug (See Figures 7 and 8, section III 1). 59

60 The display panel indicates "Program a channel" which means that the main maintenance menu is being opened. Note: The main menu cannot be accessed if the batteries are flat. The user is warned by the following message: "Maintenance impossible". You can continue by connecting up the mains power supply unit or by replacing the battery. Carry out the maintenance access procedure (See III 1). Selecting the "Replace explosimetric cell" menu? The display panel indicates: Program a channel? Press the "Up" arrow key twice. The display panel indicates: Change explo. cell? Validate that choice by pressing the "ENTER" key. The display panel indicates: Standard gas 1.00% CH4 Entering the value of the standard gas This procedure defines the content level of the standard gas to be injected into the explosimetric cell during this calibrating operation. The maximum permissible content level is 5.00% CH4; The display panel now indicates: "standard gas". You can modify the value displayed, as follows:? Select the units by repeatedly pressing the "Up" arrow key. When the desired figure is displayed, press the "Right" arrow key.? Select the tenths by repeatedly pressing the "Up" arrow key When the desired figure is displayed, press the "Right" arrow key 60

61 ? Select the hundredths by repeatedly pressing the "Up" arrow key You can return to the units or tenths by pressing the "Right" arrow key When you have finished entering the value of the standard gas, press "ENTER" The value of the standard gas that will be injected is stored in memory. Adjusting the zero The following two messages appear alternately on the display panel: Wait for stabilization Then adjust zero? Press the "ENTER" key to display measurement of the zero. The display panel indicates for example: Zero 0.28% CH4? Adjust the zero with the zero adjusting potentiometer. (Turning the potentiometer in the clockwise direction increases the measurement displayed). Adjustment of zero Explosimetric cell (left-hand potentiometer) The display panel should indicate a value close to zero: Zero 0.10% CH4 61

62 If it is impossible to make the adjustment, there is a problem with the new cell. Replace the cell for the test.? Press the "ENTER" key as soon as you obtain a value as close as possible to zero. Adjusting the sensitivity Preparing the peripheral components? Fit the gas injection cap.? Connect the cylinder of standard gas to the injection cap by means of a flexible vinyl tube approximately 1 metre long, as described in Section III (Equipment required). Starting the adjusting procedure The following messages appear on the display panel in cyclic mode: Wait for stabilization Then adjust sensitivity? Press the "ENTER" key to display the measurement of sensitivity. The display panel indicates, for example: Sensitivity 0.10% CH4? Inject the standard gas. The flow must be only just audible. The measured value of this flow rate is approximately 60 litres per our maximum.? As soon as the measurement has stabilized, adjust the value displayed by means of the sensitivity adjusting potentiometer. The value is increased by turning the potentiometer in the clockwise direction.? As soon as the value obtained matches the value of the standard gas or is as close to it as possible, press "ENTER" Sensitivity adjustment Explosimetric cell (right-hand potentiometer) 62

63 Position of sensitivity adjusting device in case of replacement of explosimetric cell.? The display panel indicates: Validate? Yes: ENTER NO:? If no fault is detected and when you press "ENTER", the display panel indicates: Program a channel Problems When you press the "ENTER" key messages may appear on the display panel: after measurement of the sensitivity, the following? "Zero incorrectly adjusted": check the local atmosphere (presence of gas) and repeat the calibration. If the fault persists, replace the cell again.? "Sensitivity incorrectly adjusted": possible discrepancy between the value of the injected standard gas and the value programmed as described in the section on "Entering the value of the standard gas". Carry out the whole calibration procedure over again. If the fault persists, replace the cell again. RETURN TO USER MODE? Return the switch to the left position or remove the plug? Remove the gas injection cap The BM 22 Plus beacon is ready to use. Reminder: For the other measuring channels (OXYGEN or TOXIC GAS METERING), intelligent, precalibrated cell units are used. The appliance therefore automatically recognizes the new unit that is inserted (I) if no new calibration is required. (1) Switch off the BM 22 Plus beacon before connecting a new cell unit. 63

64 5. "CHANGE DATA/TIME" MENU This subroutine is used to update the internal calendar and clock of the BM 22 Plus beacon. These data are used to define time scales for printing or downloading memorized measurements (min., max., STEL, TLV) to a microcomputer or a printer. Selecting the maintenance menu With the appliance in operation, insert the programming plug into the DIN connector on the side of the housing. Note: The main menu cannot be accessed when the batteries are flat. The user is warned by the following message: "Maintenance is impossible". You can continue by connecting up the mains power supply unit or replacing the battery. Selecting the "Manage date and time" menu? The display panel indicates: Program a channel? Press the "Up" arrow key three times. The display panel indicates: Manage date and time? Validate your choice by pressing the "ENTER" key. Changing the date The display panel indicates, for example: Date : 15 : 10 : 93 64

65 ? Select the required position in the date by repeatedly pressing the "right" arrow key.? Display the desired value for the position by repeatedly pressing the "Up" arrow key.? Repeat those two steps until you obtain the desired date and then press "ENTER". Changing the time The time is not incremented on the display./ The display panel indicates hours, minutes and seconds, from left to right. For example: Time: 17 : 23 : 03? Select a position in the number representing the hour by repeatedly pressing the "Right" arrow key? Display the desired value for that position by repeatedly pressing the "Up" arrow key.? Repeat those two operations until you obtain the desired hour and then press "ENTER". Confirming the date and time The following message is displayed: Validate? Oui : ENTER NO: As soon as you press:? the "ENTER" key, the data previously entered is stored in memory and you return to the main menu;? any key other than "ENTER", the data entered during this operation is lost and the initial values stored in memory before starting this procedure are preserved. You then return to the main menu. 65

66 Return to user mode? Remove the programming plug.? The BM 22 Plus beacon is ready to use. Loss of date and time When the BM 22 Plus beacon is switched off, the electronic circuits for the date and time are supplied with power by a separate lithium battery. This battery has an estimated service life of between 3 and 5 years. It must be changed after that period of time, if the time is inaccurate or if it is impossible to store the date in memory. Lithium battery IV. CHARGERS 1. DESCRIPTION The CR 22 charger is a wall-mounted type charger (designed to be fitted on a vertical support). 66

67 2. RECHARGING THE BATTERY Item 4 Battery receptacle (item 1) Battery attaching screws (item 2) Battery fitted on beacon: Switch off the beacon. Hook the beacon onto the wall-mounted charger connected to the 220 V mains power supply. Screw the female connector onto the male connector on the beacon (item 1). Battery removed from beacon: (item 4) Loosen the attaching screws (item 2). Detach the battery from the beacon. Place the battery on top of the charger and proceed as described above. Note: The battery can be changed in explosive environments. Using the master switch located in the cell compartment. 3. OPERATION GREEN LED (1) Item 1 Item 1 67