INSTRUCTION MANUAL T-935-FO ANALOGUE. TECSYSTEM S.r.l. TECSYSTEM S.r.l. protection relays. 12 protection relays

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TEST CERTIFICATE MOD. T-935 The monitoring unit has been tested according to the following procedure: TEST PROT. TEST DESCRIPTION INSTRUCTION MANUAL 1 A Buttons working 2 A Relays contacts test 3 A General mechanics test 4 A Calibration and linearization at 100 and 200 C 5 A Programming cycle test 6 B/C Accuracy test at 60 C (±1%) 7 A Power supply test at 20/270 Vac-dc 8 A 50 hours working 9 B/C Dielectric test between phase-ground and ground T-935-FO ANALOGUE 10 B/C Electric noise on power supply line and sensor line TEST PROTOCOL DESCRIPTION : A = All the units B = Every 100 units C = Extra-price certificate DATE OF TEST : SERIES NUMBER: RESULT:. VIA VITTORIO ALFIERI, 1 20090 CESANO BOSCONE (MI) TEL (02) 4581861 FAX (02) 48600783. Via V. Alfieri, 1 20090 Cesano Boscone (MI) tel. +39-2 4581861 r.a. Fax: +39-2 48600783 http://www.tecsystem.it 12

ANALOGUE OUTPUT 4-20 ma TRANSMISSION Due to the introduction of more and more sophisticated long-range control devices of variables such as the working temperature of Medium Voltage transformers and to their more elaborate protection system, it was necessary to develop our new monitoring unit, Mod. T-935 FO/ANAL. Through a special electronic circuit this unit sends an analogue signal (4-20 ma) within the set temperature range (0-200 C). This analogue signal can be handled in two different ways: - it can be sent at distance to an analogue temperature display either electromechanical or electronic. - it can be sent to a pc, through an A/D conversion card to be later sent to a more sophisticated monitoring system. FIG.1 ELECTRICAL CONNECTIONS T-935 Pt100 SENSOR CONNECTION CH 1 CH 2 CH 3 CH 4 13 14 15 16 17 18 19 20 21 22 23 24 In order to make the signal transport system more reliable the T935 FO/ANAL unit is equipped with an external power supplier operating the Pt100/4-20 ma signal conversion card inside the unit. There are two kinds of power suppliers: one with a fixed voltage 220VAC input (Mod. A420); the other with the universal voltage input, from 20 to 240 VAC-DC (Mod. AU420). The output voltage is 24 VDC. See figure no.2 for power supplier connection to T935 FO/ANAL unit. ALARM AND FAN RELAYS CONNECTION 1 2 3 4 5 6 7 8 9 10 11 50 51 ALARM TRIP FAULT FAN 1 FAN 2 Pt100 + - Vcc Gnd TECNICAL SPECIFICATION 42 41 40 POWER SUP- PLY WITHE RED RED 70 71 72 73 OUT 4-20 ma MOD.AU420 MOD.A420 Universal input voltage: from 24V to 240V AC/DC 50/60Hz Power required: 1.5 VA Output voltage: 24 VCC ±5% Max. current delivered: 50 ma Dimension: 100 x 105 h 56 mm ABS self-extinguishing housing Galvanic insulation between IN-OUT 2500 VAC Operating temperature: from 0 to 60 C max. Max. ambient humidity: 90%RH no condensing Fault signal relay for lack of input voltage Input voltage: 220VAC 50Hz ±10% Power required: 1.5 VA Output voltage: 24 VCC ±5% Max.current delivered: 50 ma Dimension: 95 x 35 h 58 mm ABS self-extinguishing housing Galvanic insulation between IN-OUT 2500 VAC Operating temperature: from 0 to 60 C max. Max ambient humidity:90%rh no condensing Fault signal relay for lack of input voltage IN 24-240V CA/CC PER AU 4-20 IN 220V CA PER A4-20 FIG.2 AU 4-20/A4-20 40 41 42 72 73 A4-20, AU4-20 ELECTRICAL CONNECTIONS 72 73 IN 24/240V CA/CC 40 41 42 T-935 FO ANALOGI- 70 71 OUT 4-20 ma + - 2 11

FAULT DIAGNOSTIC The unit doesn t switch on even if there is voltage to the terminals The CH4 is in FAULT FOC (Only three Pt100 sensors are connected) One of the 3/4 channels is in FAULT for FOC/FCC During the main switch manoeuvre ON-OFF, the ALARM and TRIP relays energize All the Pt100 sensors are in FCC. The temperature indicated by 1 or more channels is wrong. Sudden release of the main switch with a normanl temperature level. A single channel caused the unhooking. CAUSES AND REMEDIES Connector not well fit in its place. Connection wires not well closed in the clamp Burnt power supplier. Wrong programming of the unit. Check the sensors Pt100 connection. Probable damaged sensor. Strong electrical noises on the power supply line. Plug in the PT-73. Check if the shield of the signal transport cable is connected to the ground on the side of the panel. If you have no shielded cable, you have to put it. (Mod. CT-ES). If it is not available, twist the three connecting Wrong connection of the sensors. Upsidedown terminal board. Check the connections and the terminal Contact Technical Dept. of TECSYSTEM S. r.l. Pt100 sensor defective (Fcd). Substitute the sensor.check the measure signal terminal board. Set Fcd function (see page 5). Should the Fcd Fault signal appear on the display again, AUXILIARY POWER SUPPLY Rated voltage 24-240 Vac-dc Maximum ratings 20-270 Vac-dc INPUTS 4 inputs RTD Pt100 sensors-3 wires removable rear terminals input channels protected against electromagnetic noises and spikes sensors length cables compensation up to 500 m (1 mm²) opt. Analog inputs 4-20 ma (range 0-200 TESTS AND PERFORMANCES Assembling in accordance with CE rules Protection against electrical and magnetic noises CEI-EN50081-250082-2 Dielectric strength: 2500 Vac for 1 minute from relays to sensors,relays to power supply, power supply to sensors Accuracy: ± 1% full scale, ± 1 digit Ambient operating temperature 20 C to +60 C Humidity 90% no-condensing ABS self-extinguishing housing-noryl 94VO Frontal polycarbonate-ip65 Burden 3VA Data storage 10 years minimum Digital linearity of sensors signal Self-diagnostic circuit Opt. Frontal plastic protection Opt. Protection treatment of electronic part DIMENSIONS 96X96MM-DIN43700-prof. 140mm (with rear terminals) COMMUNICATION Not available in this model OUTPUTS 2 alarm relays (ALARM-TRIP) 2 alarm relays for fan control (FAN1-FAN2) 1 alarm relay for sensor fault or working anomaly (FAULT) output contacts capacity: 5A-250Vac res. Output relays test DISPLAYNG AND DATA MANAGEMENT 1 dispaly 13mm high with 3 digits for displaying temperatures led for displaying reference channel led indicating alarm or trip channel led indicating fault temperature monitoring from 0 C to 200 C 2 alarm thresholds 2 alarm ON-OFF thresholds for fan control sensors diagnostic (Fcc-Foc- Fcd) entering the programming by frontal push button automatic output from programming cycle after 1 minute of no-operation wrong programming automatic display programmed data call out possibility of set automatic channel scanning, hottest channel, manual scanning maximum temperatures and alarm reached storage frontal alarm RESET push button possibility of set HOLD function for output relays 10 3

MOUNTING Make a hole with the dimensions of 92x92 mm in the panel plate. Fasten firmly the unit by the fixing blocks you are equipped with. POWER SUPPLY The T-935 unit has a Universal Power Supply: it can be supplied indifferently from 24 to 240 Vac-dc without any respect to the polarities. This feature is obtained by the application of a tried power supplier which provides the installer free from the worries concerning the correct Vac or Vdc power supply. The ground cable must always be fixed to the clamp 41. When the unit is supplied directly from the secondary of the transformers to protect, it can be fulminated by high intensity overvoltage. This happens when the locking of the master switch is connected without charge. This is much more evident when the 220 Vac voltage is obtained directly from the bars of the secondary of the transformers and there is a fixed phase adjustment condenser of the same transformer. In order to protect the electronic apparatus, we recommend the application of the electronic discharges of the series PT-73 - mono or double phase - which have been studied by Tecsystem Srl for this specific purpose. Alternatively, we recommend the application of a power supply by 24 Vac or better 24 Vdc. PROGRAMMING REHABILITATION IN CASE OF BLOCK (Prg no) If the programming has been blocked (step 24), in order to enter again the programming of the unit, it is necessary to carry out the following unblocking procedure : enter the program vision way pushing PRG keep TEST pushed until PRG stops to lighten. ( LED PROGRAM alight ) During the blocking, pushing PRG for more than two seconds, on the display nop appears to indicate the impossibility to program the data. WARRANTY The T series units are under warranty for 12 months from the delivery date marked on the unit. The warranty is recognised when the unit breaks down due to some production faults or insufficient calibration. The warranty is not valid when the unit is tampered with or when it has been damaged for a wrong sensors connection or wrong power supply, out of the max working limits (20 270 Vacdc). The warranty is not valid when the unit has been fulminated by eccessive transitory voltages. In this case TECSYSTEM Srl does not answer for damages caused by faulted or defective units. All the delivery expenses (there and back) of the unit must be payed by the Customer.(ANIMA prices, Col. C.). In case of dispute, the qualified FORUM is the one in Milan. The warranty is always EXW our Company in CESANO BOSCONE. ALARMS AND FAN CONTROL ELECTRICAL CONNECTIONS Carry out the electrical connections on the extractable terminal board after having taken them off from the apparatus (follow the Fig.1). ALARM and TRIP relays energize only when the prefixed temperature limits are reached. The FAULT relay energizes when the apparatus is supplied and it de-energizes when the Pt100 are damaged or when there is no power supply voltage. FAN 1 and FAN 2 relays can be used for cooling-fan control or else they can be fit into the conditioning circuit of the transformer box. THERMOMETRIC SENSORS CONNECTION Each Pt100 sensor has three conductors : one white and two red (CEI 75.8) The Fig.1 shows the disposition in the terminal board of the connection cables to the unit. The CH2 channel must be always refired to the central column of the transfomer. The CH4 channel must be always refired to the core of the transformer or else to the ambient Pt100 sensor, if you want to keep the box of the transformer under thermic control by the T- 935 unit. PT100 EXTENSION CABLE: TECHNICAL SPECIFICATIONS Cable 22xAWG 20/19 cu/stg Section 0,55 mm² Antiflame Insulation PVC105 In accordance with CEI 20.35 IEC 332.1 Max. working temperature: 105 C Conformation : 4 terns of the numbered conductors (1-1-1...4-4-4) WWR twisted and coloured conductors Shield cu/stg PVC Antiflame protecting covering External diameter 9,0 mm Skeins of 100 m 4 9

N PUSH BUT- TONS 1 PRG/SET EFFECT Keep the push button pressed for 7 until Set appears and PRG starts to lighten. When PRG stops lightening the set DEFAULT ALARM temperature will appear on the display 2 set up the established limit 3 PRG/SET TRIP set T appears 4 set up the established limit 5 PRG/SET FAN appears 6 set up FAN YES or NO 7 PRG/SET on the display appears OFF 8 PRG/SET the OFF T appears NOTES Led program alight YES:FAN connected NO: FAN disconnected 9 set up the temperature only if at the step 6 you established YES 10 PRG/SET on the display appears ON 11 PRG/SET the ON T appears 12 set up the temperature only if at the step 6 you established YES 13 PRG/SET on display appears CH4 14 set up CH4 YES or NO 15 PRG/SET way of FAN control on the display appears CHF YES: CH4 connected NO: CH4 disconnected 16 set up CH 1,2,3 or CH4 respective LED alight 17 PRG/SET way of FAN control TEST on the display appears h00 18 set up the number of hours 19 PRG/SET on display appears HLd 20 set up HLd YES or NO 21 PRG/SET on display appears Fcd 22 set up Fcd YES or no 23 PRG/SET Prg appears on display only if at the step 6 you established YES h00=function disconnected with HLd YES function HOLD established Fcd YES= control of damaged Pt100 connected 24 set up Prg YES or NO Prg NO= the programming is blocked 25 ENT out of the programming lamp test 26 PRG/SET return to step 1 to set up FAN2 repeat the same procedure as FAN1 MEASURE SIGNALS TRANSPORT All the transport cables of the Pt100 measure signals must absolutely: be divided from the power ones be realized with shielded cable with twisted conductors have a section of min 0,5 mm² be twisted if you have no shield be firmly fixed in the terminal board have tinned or silvered conductors All the T series units have the sensors linearization with a max error of 0,5% v.f.s.. TECSYSTEM srl has realised a special cable for the measure signal transport with all the protection requirements according to CEI Norms: mod. CT-ES THERMOMETRIC SENSORS DIAGNOSTIC In case of damage of one of the thermometric sensors which are installed on the machine to protect, the FAULT relays energizes immediately, the ALARM and TRIP LED of the damaged channel (Chn) lighten and the FAULT LED is lightening. The kind of sensor damage will automatically appear on the display. It can be: Fcc if the sensor is in short circuit Foc if the sensor is disconnected SENSOR TEST DEVICE Fcd (damaged sensor) During the normal working of the unit, if you programmed Fcd/YES the display will signal by Fcd that a sensor is damaged and the LED which corresponds to the respective channel will lighten (Chn). The FAULT relay energizes giving a signal to the operator. After the replacement of the damaged sensor, you can RESET the alarm pushing RESET until RST appears on the display. TEMPERATURES DIAGNOSTIC When one of the thermometric sensors surveys a temperature which is 1 C above the alarm limit, after 4 seconds the ALARM relay will energize and the ALARM LED of the respective channel (Chn) will switch on. We have the same situation when the TRIP temperature limit is surveyed: we have the energizing of the TRIP relay and the lighting of the LED TRIP of the respective channel (CHn). Then the surveyed temperature falls of 1 C below the prefixed limit for the ALARM and TRIP switching, the relays deenergize and the respective LEDS switch off. 8 5

COOLING-FAN CONTROL The T-935 FO/ANAL unit, if suitably programmed, can control the ON/OFF condition of the transformer fans according to the two different levels of set temperatures. The transformer sidefans or the air-drifting fans can be controlled in two different ways: using the temperatures surveyed by the sensors on the three columns CHF 1.2.3 - CH4 excluded ALARM and TRIP LED CH1.2.3 switched on (ex. F1: ON at 80 C - OFF at 70 C) (ex. F2: ON at 90 C - OFF at 79 C) by an additonal sensor (CH4/YES) for the ambient temperature in the transformer box. CHF 4 ALARM e TRIP LED Ch4 switched on (ex. F1: ON at 40 C - OFF at 30 C) (ex. F2: ON at 45 C - OFF at 35 C) You can select it by UP and DOWN push-buttons. FAN TEST By programming (hxx) you can establish to have the fans set for 5 minutes every xx hours, independently on columns or ambient temperature values. This function has the purpose to verify periodically the fans working, when they are not utilized. Establishing h00 this functions is excluded. HOLD FUNCTION If you set up by programming HLD-YES, ALARM and TRIP relays will be energized until the manual reset when the temperature falls down below the set alarm thresholds. If you do not want this function you have to establish HLD no by up and dowm push-buttons. DISPLAY MODE Pressing on DISPLAY MODE you establish the visualization ways of the display: HOT: the unit visualizes automatically the hottest channel MAN : manual reading of the channels temperature by UP and DOWN push-buttons T.MAX :the unit visualizes the max. temperature reached by the sensors and the possible alarms starting from last reset. To check the channels press UP and DOWN. SCAN : channels are ciclely every 2 seconds WORKING PROGRAM CONROL In order to control the programmed temperature values, you have to push shortly on PRG. By pushing PRG repeatedly the values previously established appear on the display in sequence. In order to end the visualization you have to push ENT. LAMP TEST It is advisable to carry out regularly the LED test of the unit. For this operation you have to push TEST. If one of the LEDS does not work, please send us the unit in order to be repaired. ALARM RELAYS TEST This function allows to test the relays working without any additional instrument. To carry out the test you have to push TEST for 5 seconds: all the LED will switch on and tst lightening will appear on the display. Release it when the RELAY TEST LED will be alight. The first relay to test will be indicated by the display and the respective LED will be alight. The relays to test will be indicated on the display by: Fan 1 : 1st cooling relay Fan 2 : 2nd cooling relay Flt : Pt100 fault relay Alr : alarm relay trp : trip relay Select the relay to test by UP and DOWN push-buttons. Energize it by pushing SET and deenergize it by pushing RESET. In order to stop this procedure, you have to push again TEST and all the relays will be restored to the starting configuration. After 5 minutes of inactivity of the keyboard, the TEST RELAY procedure will be automatically interrupted. ALARM RELAY EXCLUSION If you want to exclude the alarm signal, you have to push RESET: the relay de-energizes and the respective LED, which was alight, starts to lighten. If the transformer temperature is still rising, the ALARM relay will energize again until the temperature value falls down to 5 C below TRIP threshold. In this moment the user can exclude the ALARM again, but in this case, it will not appear any other indication as regards to ALARM relay. The exclusion system will be automatically disconnected when the temperature falls down the ALARM threshold. IMPORTANT NOTICE Before making the insulation test on the electrical panel on which the unit is installed, you must take it off from the power supply in order to keep it out of damage. 6 7