SK-6_ADD#7 FACILITY. TORONTO WATER Operational Support - Capital Works Delivery

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4 SCALE: DATE: DRAFTING: NTS 2017/02/23 PR FACILITY GROUP 5 - REHABILITATION AND UPGRADES TO SEVEN(7) SEWAGE PUMPING STATIONS TORONTO WATER Operational Support - Capital Works Delivery DRAWING NUMBER: SK-6_ADD#7

5 - - N.T.S. SCALE: DATE: DRAFTING: NTS 2017/03/01 PR FACILITY GROUP 5 - REHABILITATION AND UPGRADES TO SEVEN(7) SEWAGE PUMPING STATIONS TORONTO WATER Operational Support - Capital Works Delivery DRAWING NUMBER: SK-7_ADD#7

6 SCALE: DATE: DRAFTING: NTS 2017/03/14 PR FACILITY GROUP 5 - REHABILITATION AND UPGRADES TO SEVEN(7) SEWAGE PUMPING STATIONS TORONTO WATER Operational Support - Capital Works Delivery DRAWING NUMBER: SK-8_ADD#7

7 CONCRETE WALL / SLAB OPENING SEALING DETAIL SCALE: DATE: DRAFTING: NTS 2017/03/14 PR FACILITY GROUP 5 - REHABILITATION AND UPGRADES TO SEVEN(7) SEWAGE PUMPING STATIONS TORONTO WATER Operational Support - Capital Works Delivery DRAWING NUMBER: SK-9_ADD#7

8 SCALE: DATE: DRAFTING: NTS 2017/03/14 PR FACILITY GROUP 5 - REHABILITATION AND UPGRADES TO SEVEN(7) SEWAGE PUMPING STATIONS TORONTO WATER Operational Support - Capital Works Delivery DRAWING NUMBER: SK-10_ADD#7

9 WASTEWATER COLLECTION Group 5 Pumping Stations Process Control Testing Procedure Version Date Description of Revision % Review 1.0 Tender (Addendum 7) Strachan Sewage Pumping Station Version 0.1 WSP Inc. Page 1 of 26

10 Strachan Sewage Pumping Station Version 0.1 WSP Inc. Page 2 of 26

11 Table of Contents PURPOSE...4 GLOSSARY OF ACRONYMS...5 SECTION 1 PURPOSE OF INSTRUMENT AND THE TESTING PROCEDURE LEVEL MONITORING Float Switches Ultrasonic Level Transmitter FLOW MONITORING Magnetic Flow Meter (Pumping Rate Out Of Station) Thermal Flow Meter (City Water) Weir Flow Meter (Overflow) PRESSURE MONITORING Pressure Gauges Pressure Transmitter GAS DETECTION / MONITORING Gas Detection Transmitters BUILDING (SECURITY, DOOR CONTACTS AND SMOKE DETECTORS) Door Contacts Smoke Detectors...15 SECTION 2 PURPOSE OF EQUIPMENT AND THE TESTING PROCEDURE HEATING VENTILATION AND AIR CONDITIONING (HVAC) MOTOR OPERATED VALVES AND KNIFE GATES PUMPS Local Mode Remote Mode (RPU Control) Backup (Float Mode) EMERGENCY POWER Generator Automatic Transfer Switch (ATS)...25 LIST OF TABLES Table 1: Referenced Documents...4 Table 2: Float Mismatch Alarm Truth Table...7 Table 3: Valid Float Positions Truth Table...7 Table 4: Interface Test Points...20 LIST OF FIGURES Figure 1: Pump(s) Speed vs. Wet Well Level curves...22 Strachan Sewage Pumping Station Version 0.1 WSP Inc. Page 3 of 26

12 Purpose This document is intended to be used as a guideline of the testing procedure that the system integrator shall perform and demonstrate to Contractor and Owner during the Commissioning Process. The intent is that the expected outcome of the test is described as well as the reasoning and intent. It is expected and intended that all pump stations function and behave in similar standard manner such that the operators can easily and identify abnormal conditions and allow the operator to address and operate the station in a consistent and systematic manner. This document is not location specific but rather a general document to be used for all Group 5 Pump Stations, as such, it is to be used in conjunction with a number of other supporting documents most importantly: the Process Control Narratives and the P&IDs of the particular pump station. Other supporting documents are listed in the table below: Table 1: Referenced Documents Document Name / Title/ Description Document Number Revision Process Control Narratives (Site Specific) (Latest) P&ID (Site Specific) (Latest) Testing Procedure Specification Strachan Sewage Pumping Station Version 0.1 WSP Inc. Page 4 of 26

13 GLOSSARY OF ACRONYMS ACP ACU AHU ATS BL CMMS CSO eops FN GAC HMI HVAC I/O kv kva LCP LED LIMS L/min L/s MCC ML/d ML/h m ma m*g/l mm NFPA820 NPSH OIT PAC PCS P&ID PLC POMS RPU SCADA STS UPS V WAN Area Control Panel Access Control Unit Air Handling Unit Automatic Transfer Switch Blower Computerized Maintenance Management System Combined Sewer Operations Electronic Operations Fan Granular Activated Carbon Human Machine Interface Heating, Ventilation and Air Conditioning Input/Output kilovolt kilovolt-amp Local Control Panel Light Emitting Diode Laboratory Information Management System Litres per minute Litres per second Motor Control Centre Megalitre per day Megalitre per hour meters milliamps milligrams per Litre millimeters Standard for Fire Protection in Wastewater Treatment and Collection Facilities Net Positive Suction Head Operator Interface Terminal Powder Activated Carbon Process Control System Process & Instrumentation Diagram Programmable Logical Controller Process Optimization Management System Remote Processing Unit Supervisory Control and Data Acquisition Sanitary Trunk Sewer Uninterruptible Power Supply Volt Wide Area Network Strachan Sewage Pumping Station Version 0.1 WSP Inc. Page 5 of 26

14 Section 1 Purpose of Instrument and the Testing Procedure The following is a description of the devices, how they work, what their role is in this application, how they are to be tested and what the expectations are. 1.1 Level Monitoring The liquid level in each wetwell is monitored by float level switches and ultrasonic level transmitters Float Switches Description The float level switches are exactly as they sound; devices that hang down when water level is below them (their elevation from the bottom of the wetwell is the set point ) and float up as the liquid level rises, as they float they close a contact and give a signal to the PLC indicating the liquid level has reached them. It is not uncommon for these devices to fail due to buildup of material on the surface of the device, causing it to loose it s buoyancy and not float, or they can float up and get tangled or stuck in an upside down position causing it to falsely report liquid level above its position, or the signal wire can break or short out, or simply they may fail internally as can any other device. Since these instruments are used as a backup system, it is critical that their failure is detected immediately and alarm the operator to investigate and repair the fault. For process control details please review the process Control Narratives (PCN). Testing Procedure It is important to test the normal operation, as well as the abnormal circumstances or failures. In order to test the functionality of the device and the configuration, each float shall be tilted (floating). The liquid level can be raised and lowered to demonstrate the following (noting that manual intervention may be required to demonstrate the Abnormal Conditions/Failure): Normal Operation As the level floats are tilted, their status should be indicated on the OIT/HMI. On the HMI and OIT a hanging float is indicated by a white filled Circle, while a tilted float is indicated by a red filled circle. An alarm condition is indicated by a blinking. Specifically if the High-High float is tilted, it indicates an alarm condition and shall be shown as Blinking Red circle, while a hanging Low-Low float will be indicated by a blinking White circle. If an interlock/action/alarm is triggered (as described in the PCN) then this action is to be confirmed in the field and HMI/OIT. For all alarm conditions, ensure they are correctly reported in the Alarm Summery and Alarm Log (HMI and OIT). Each time a float changes it's state, it the LIT value(indicating the water level in the well) should be picked up and displayed in a box next to Float switch. Abnormal Condition / Failure In order to detect failure, the PLC monitors the sequence in which the floats tilt as the level rises and drops. A Mismatch Alarm is triggered if the floats switch in the wrong sequence. For example, it s not natural for the LSLL to hang while the LSL is tilted as this would indicate the level is above the LSLL elevation but the float has not tilted, conversely it can indicate that the level is below the LSL yet the float is tilted when it should be hanging. It is expected that every combination of float switch failure be tested and confirmed that a Mismatch Alarm is generated and correctly indicated on the HMI/OIT (Blinking). See the Table 2: Float Mismatch Alarm Truth Table for the required test combinations leading to alarm conditions and Table 3: Valid Float Positions Truth Table illustrates all valid combinations. If an interlock/action/alarm is triggered (as described in the PCN) then this action is to be confirmed in the field and HMI/OIT. For all alarm conditions, ensure they are correctly reported in the Alarm Summery and Alarm Log (HMI and OIT). Strachan Sewage Pumping Station Version 0.1 WSP Inc. Page 6 of 26

15 LoLo Alarm Table 2: Float Mismatch Alarm Truth Table Lo Alarm/ Stop Pump(s) Hi Alarm/ Start Pump(s) HiHi Alarm/ Backup Mode Flood Alarm Mismatch Alarm LSLL-0001 LSL-0002 LSH-0003 LSHH-0004 LSHH-0005 Alarm Hanging Tilted Either Either Either TRUE Hanging Either Tilted Either Either TRUE Hanging Either Either Tilted Either TRUE Hanging Either Either Either Tilted TRUE Either Hanging Tilted Either Either TRUE Either Hanging Either Tilted Either TRUE Either Hanging Either Either Tilted TRUE Either Either Hanging Tilted Either TRUE Either Either Hanging Either Tilted TRUE Either Either Either Hanging Tilted TRUE Note: In Table 2, the cells marked with Either require that both the Tilted and Hanging state Amust be checked to ensure both conditions give the same result. LoLo Alarm Table 3: Valid Float Positions Truth Table Lo Alarm/ Stop Pump(s) Hi Alarm/ Start Pump(s) HiHi Alarm/ Backup Mode Flood Alarm Mismatch Alarm LSLL-0001 LSL-0002 LSH-0003 LSHH-0004 LSHH-0005 Alarm Hanging Hanging Hanging Hanging Hanging FALSE Tilted Hanging Hanging Hanging Hanging FALSE Tilted Tilted Hanging Hanging Hanging FALSE Tilted Tilted Tilted Hanging Hanging FALSE Tilted Tilted Tilted Tilted Hanging FALSE Tilted Tilted Tilted Tilted Tilted FALSE Ultrasonic Level Transmitter Description The exact level of liquid in the wetwell is monitored by an ultrasonic level transmitter. This device works on the principle of sending an ultrasonic pulse directed into the wetwell and measuring how long it takes for the echo to bounce of the liquid surface and travel back to the transmitter. Inherently the device is susceptible to failure caused by a number of variables, such as changes in well geometry, articles providing false echoes such as walkways or protrusions from the walls, but most notably build up on the transmitter/receiver element itself. Sludge/dirt coating on the element itself can cause either the ultrasonic pulse to not be transmitted correctly, or not be received correctly. This failure is called Loss or Echo and it indicates that it cannot determine the level in the wetwell. Since this device is the primary device for pump control, it is critical that failure is detected, indicated and an alarm is generated so the operator can investigate and have it repaired. Strachan Sewage Pumping Station Version 0.1 WSP Inc. Page 7 of 26

16 For process control details please review the process Control Narratives (PCN). Testing Procedure It is important to test the normal operation, as well as the abnormal circumstances or failures. The ultrasonic transmitter performance must be tested throughout the entire operating range of the pump station. The Min/Max and engineering units must be configured correctly in the RPU, SCADA, Level transmitter, and they must correspond to the calibration sheet. Testing the failure will require manual intervention. Normal Operation With the wet well liquid level at the lowest point, ensure the reported value on the transmitter itself (loc al display) is in agreement with the OIT and HMI value. Observe and trend as the wetwell level is increased paying particular attention to rate of change and spikes or jumps in level indication or discrepancies between actual physical level and the reported level as this indicative of false echoes and poor signals. Any such abnormalities must be investigated. If an interlock/action/alarm is triggered (as described in the PCN) then this action is to be confirmed in the field and HMI/OIT. For all alarm conditions, ensure they are correctly reported in the Alarm Summery and Alarm Log (HMI and OIT). Abnormal Condition / Failure There are a number of abnormal conditions that must be tested for: - Signal out of range (High) Use 4-20mA simulator to demonstrate An alarm is generated and the condition must be shown on the HMI/OIT by flashing the level indication. - Signal out of range (Low) Use 4-20mA simulator to demonstrate or simply open loop An alarm is generated and the condition must be shown on the HMI/OIT by flashing the level indication. - Loss of Echo (LOE) - Use an object to physically block the US pulse. An alarm is generated and the condition must be shown on the HMI/OIT by flashing the letters LOE beside the level indication. Under all of the above, ensure the correct alarm is generated and that it is reasonably clear to the operator. The intent is that these alarms are used for trouble shooting and must be clear enough to give the operator a clue where to begin his investigation. Strachan Sewage Pumping Station Version 0.1 WSP Inc. Page 8 of 26

17 1.2 Flow Monitoring Sewage flow in and out of the station is monitored in a couple of different ways. Further the city water flowing into the station is also monitored. This section describes the differences and how each must be tested Magnetic Flow Meter (Pumping Rate Out Of Station) Description The sewage being pumped out of the station is monitored by Magnetic Flow Meters. These flow meters are great in that they offer a non-intrusive measuring technology, where there are no moving parts or any obstruction to the flow. The Magnetic Flow Meter operates on the premise that any conductive material (sewage is actually a conductive material) moving through a magnetic field will induce a electric field which in turn will induce an electromagnetic field. The mag-meter will generate a fixed and well calibrated electromagnetic field in path of the fluid, as the fluid passes, it will distort this field. Although minute in amplitude, the magnetic flow meter is designed to detect this distortion or deviation that the moving fluid is creating. Based on this distortion, the magnetic flow meter can determine the velocity at which the liquid is flowing. The full mechanics are much more complex and beyond the scope of this document. The total flow rate being pumped out of the pump station is measured by such device and a 4-20mA analog signal is sent to the RPU representing the current flow rate. Further, the device is also equipped with a built in totalizer to keep track of the total flow being pumped. This totalized value is communicated to the RPU via a serial communication link (Modbus in this case). It is also possible to implement a software totalizer in the RPU however this method is susceptible to error, when the PLC is offline, or the current flow signal is interrupted. For this reason, and to eliminate the possibility of the RPU total and the local total value disagreeing, only the local totalizer shall be used, and the value is simply read into the RPU. It is important to note that if the flow meter is replaced, the total is reset to zero. This is also the case when the total counter overflows (essentially it gets to , and begins again form ). Provision must be made in the RPU programming to detect this scenario, and simply add the new reading to the last valid reading received thus maintaining a total true value. Since the flow meter is a critical instrument in measuring the stations efficiency and use, it is monitored for failure by the RPU. For process control details please review the process Control Narratives (PCN). Testing Procedure It is important to test the normal operation, as well as the abnormal circumstances or failures. Fist item to be confirmed is the range. The Min/Max and engineering units must be configured correctly in the RPU, SCADA, Flow transmitter, and they must correspond to the calibration sheet. Any discrepancies will result in disagreement between actual flow, locally reported flow at the transmitter, and remotely indicated flow at the SCADA. The totalized flow unit of measurement must be noted and correctly configured at the transmitter and in the PLC and SCADA. As this is a complex device and comes with a certificate of calibration, it is not necessary to validate the accuracy but rather its integration into the System. In order to test the functionality of the device and the configuration, fluid must be pumped through the lines and both normal and abnormal conditions must be checked: Normal Operation Zero-flow condition - this is a very critical item as an incorrect value will cause incorrect totalized flow values. With the valve closed downstream, of the flow meter, it can be assumed that no flow exists. The instrument must read true zero (0.0) flow locally, and at the RPU and SCADA. At the same time the flow meter configuration must be checked to ensure the zero flow threshold is set correctly. (Critical to this test is the grounding and installation of the device, for this refer to the manufacturer insulation requirements.) Before the flow check, all the necessary valves upstream and downstream of the flow meter must be opened. Following the proper pump starting procedure, flow can be established by operating one of the pumps. With the flow at steady state, verify that the local reading, the RPU and SCADA reading are all in agreement. Verify the Strachan Sewage Pumping Station Version 0.1 WSP Inc. Page 9 of 26

18 totalizer local reading and RPU/SCADA readings are in agreement. Verify that the correct number of decimal places is shown on the HMI/OIT and that the pop-ups are displayed correctly. Depending on the number of pumps running, the alarm setpoints for the flow transmitter must also change. Ensure that there are separate sets of Lo-Lo, Lo, Hi and Hi-Hi alarm setpoints for different number of running pumps. If an interlock/action/alarm is triggered (as described in the PCN) then this action is to be confirmed in the field and HMI/OIT. For all alarm conditions, ensure they are correctly reported in the Alarm Summery and Alarm Log (HMI and OIT). Abnormal Condition / Failure The flow meter is a fairly robust instrument however it is sensitive to a number of abnormal circumstances: - Reverse flow - Ensure the flow meter does not totalize negative (reverse flow), ensure the flow meter element (tube) is installed in the correct direction. This can be tested by isolating the flow element upstream of flow tube and draining some of the fluid causing a reverse flow. - Partially filled pile or empty pipe Although the station is designed such that the flow meter does not drain, and the pipe is maintained full, it is important that under these conditions the flow meter reading remains true as false readings will corrupt the totalized value. This can be tested by isolating the flow tube and draining some or all the fluid. - General Failure - In order to detect failure, a general fault output is generated at the flow meter and is monitored by the RPU. This is an alarm condition and is indicated at the HMI/OIT. Alarm is generated and correctly indicated on the HMI/OIT (Blinking). If an interlock/action/alarm is triggered (as described in the PCN) then this action is to be confirmed in the field and HMI/OIT. For all alarm conditions, ensure they are correctly reported in the Alarm Summery and Alarm Log (HMI and OIT) Thermal Flow Meter (City Water) Description The thermal flow meter works on the principle that as a fluid passes over a heated element, heat is removed by the passing fluid and the element cools. By measuring the rate at which the element is cooled and comparing this to known heat dissipation model the flow rate of the fluid is calculated. The benefits of such instrument is that is has no moving parts and in clear fluids where scaling and other contamination of the element is reduced the instrument is very reliable. The 4-20mA signal representing flow is read by the RPU. Device failure is identified by the RPU when the signal drops below 4mA or rises above 20mA. Alarms, trends and totalized flow is available at SCADA for operator action. For process control details please review the process Control Narratives (PCN). Testing Procedure Thermal type flow meters generally need to be calibrated for the fluid being measured. After the calibration procedure is complete as per the manufacturer instructions. The instrument must be tested both under normal conditions as well as abnormal/fault conditions. The Min/Max and engineering units must be configured correctly in the RPU, SCADA, Flow transmitter, and they must correspond to the calibration sheet. In order to test the normal conditions, flow will need to be established, for abnormal conditions isolation and draining of the pipe may be required. Normal Operation The intent is to identify flow and ensure the operator is aware of water usage in the station, with the ultimate goal of minimizing water usage (cost savings). Under normal conditions, water usage in the station is zero. The Instrument must be tested to identify this scenario correctly. Consequently it must also detect and measure water Strachan Sewage Pumping Station Version 0.1 WSP Inc. Page 10 of 26

19 flow. The RPU shall be programmed (As per PCN) to identify non-zero flow for extended periods and trigger an alarm alerting the operator of a leak or un-wanted water usage. For all alarm conditions, ensure they are correctly reported in the Alarm Summery and Alarm Log (HMI and OIT). Abnormal Condition / Failure The only abnormal condition that can be tested for is empty pipe. It is important that the instrument can detect this scenario and report correctly (empty pipe means no-flow). Although an abnormal condition, this is not an alarm state. Instrument failure shall be identified by signal outside the 4-20mA envelope. The standard is current below 3.8mA and above 20.5mA indicating an device fault. A fault condition shall be indicated at the OIT/HMI (Blinking) If an interlock/action/alarm is triggered (as described in the PCN) then this action is to be confirmed in the field and HMI/OIT. For all alarm conditions, ensure they are correctly reported in the Alarm Summery and Alarm Log (HMI and OIT) Weir Flow Meter (Overflow) Description This type of measurement is purely computational, and is fully dependent on a level measuring instrument. The measuring concept is based on a) the fact that fluid shall over flow through a fixed area of specific and given dimensions, b) the fluid flows by gravity and c) the fluid level can be measured. Since the calculation is heavily dependent on the level measurement, the testing procedure for the level measurement instrument is covered under the level measurement section; however the computational aspect shall be tested here. For process control details please review the process Control Narratives (PCN). Testing Procedure The testing procedure for the level measurement is discussed in the Level Measurement section. The computational portion can be tested here; however since an overflow condition is undesirable, a simulated scenario shall yield the same results. Normal Operation Under normal conditions the level is far below the weir and thus the overflow rate is zero, however the calculation shall be tested throughout the full range of the level transmitter. This shall be performed by simulating a value, preferably using a 4-20mA generator however software simulation is also acceptable. The overflow rate values shall be verified against the formulae provided at a minimum of 4 points yielding non zero flow (ie. above the overflow elevation). For all alarm conditions, ensure they are correctly reported in the Alarm Summery and Alarm Log (HMI and OIT). Abnormal Condition / Failure The flow rate is dependent on the level instrument, it is important that the calculation is based on the duty level transmitter and that upon instrument failure, the duty transmitter switches and the calculation follows the correct transmitter. Since this is a strictly computational measurement, it is critical that values outside the expected range and the data types are tested for, in particular: - Negative values the indicated flow rate shall be zero - Large numbers the calculation block shall be able to handle the full range of the data type (2^16, 2^32 etc) - Zero the indicated flow rate shall be zero - Loss of Echo or Fault of both transmitters upon loss of echo alarm or fault of both level transmitter the level shall be zero. Strachan Sewage Pumping Station Version 0.1 WSP Inc. Page 11 of 26

20 1.3 Pressure Monitoring Pressure monitoring is critical to all pumping operations. In most cases pressure gauges are the first place to look during commissioning, start up and troubleshooting. Pressure gauges are the most robust and reliable instruments and are generally the fall to device. Having said that, when trending and assessing pump station performance, pressure transmitters are used. For this reason, at all pump stations pressure gauges are used to monitor each pump suction and discharge pressures while the overall station pressure is monitored by a pressure gauge as well as a pressure transmitter mounted on the discharge header of the station Pressure Gauges Description The pressure gauge technology employed is the Bourdon tube type. It is essentially a flattened tube bent into an arc, as the pressure in the tube increases the tube as a tendency to straighten (deflect). This deflection motion is linear with pressure and through mechanical advantage moves the needle on a pressure gauge. It is obvious from that description that if solid objects were to enter this tube it would potentially interfere with the instrument s operation as would plugging of this tube. For this reason diaphragm isolators are used to prevent the fluid (in this case sewage) from entering the gauge. Testing Procedure Gauges come pre calibrated and sealed, there are no field adjustments, however damage can occur during transportation, storage or installation. The pressure gauge calibration certificates must be available. Where the gauge is fitted with a block and bleed valve, the gauge can be checked for zero gauge pressure, by isolating the process fluid and bleeding any pressure in the line. The gauge shall read zero pressure at this point. It is also critical to vent out as much air as possible by first opening the block valve slightly until fluid begins to exit from the bleed port at which point the bleed valve is closed completely and the block valve is opened completely. With the pressure gauge installed and the block valve open, the gauge will most likely not read zero pressure, as it will most likely be exposed to static head pressure in the lines. Normal Operation To test the pressure gauge fully, the pump must be started. During the pump start up the gauge shall indicate increasing pressure until the pump reaches operating speed and the flow stabilizes. Abnormal Condition / Failure Change in pressure during the pump start up and shut down should be clearly visible, if the pressure gauge does not respond to pump start up and shut down, first ensure the block and bleed valves are in the correct position, the gauge is not somehow isolated from the line. Otherwise further investigation is required Pressure Transmitter Description The most common pressure transmitter technology is the piezo resistive technology. It operates on the premise that the sensor material s electrical resistance varies with pressure. Similar to the pressure gauges, the instrument is isolated from the process fluid by a diaphragm. The pressure measurement is displayed locally and the 4-20mA signal is read by the RPU. Device failure is identified by the RPU when the signal drops below 4mA or rises above 20mA. Alarms and trends are available at SCADA for operator action. For process control details please review the process Control Narratives (PCN). Testing Procedure The pressure is monitored locally by a pressure gauge as well as the pressure transmitter. Since the two are installed in proximity to each other and at the same elevation, it is natural that both devices should indicate the same pressure. The Min/Max and engineering units must be configured correctly in the RPU, SCADA, Pressure Strachan Sewage Pumping Station Version 0.1 WSP Inc. Page 12 of 26

21 transmitter, and they must correspond to the calibration sheet. Verifying that the pressure reading at 4 points on the calibration range at the OIT/HMI matches the local display and the local pressure gauge is a good indication that the configuration is correct. Normal Operation To test the pressure transmitter at 4 points throughout the range, the pump must be started and run. It will not be possible to check the full range as the pressure produced by the pumps should not reach that high. It is critical however that the pressure gauge and the pressure transmitter readings match. Depending on the number of pumps running, the alarm setpoints for the pressure transmitter must also change. Ensure that there are separate sets of Lo-Lo, Lo, Hi and Hi-Hi alarm setpoints for different number of running pumps. Abnormal Condition / Failure The pressure transmitter is a robust device and is loop powered however it does not offer a separate fault contact. The device failure is deduced by monitoring the 4-20mA signal. A transmitter failure is represented by a signal below 3.8mA or above 20.5mA. Verify the alarm is generated and correctly indicated on the HMI/OIT (Blinking). If an interlock/action/alarm is triggered (as described in the PCN) then this action is to be confirmed in the field and HMI/OIT. For all alarm conditions, ensure they are correctly reported in the Alarm Summery and Alarm Log (HMI and OIT). 1.4 Gas Detection / Monitoring The ambient air is monitored for combustible gases using an electro chemically sensitive diaphragm material. A complex electronics circuit monitors the diaphragm s electrical characteristics and using complex algorithms translates these changes into gas levels measured as a percentage of the Lower Explosive Limit (LEL). The sensing elements have a finite life and are prone to failure due to contamination and other environmental variables, in most cases they require periodic calibration. For this reason as well as the fact that these devices are categorized as safety devices, they are fitted with self-diagnostics circuitry and measures. A discrete contact is dedicated to indicating Device Failure while separate 4-20mA signals are used for the gas level readings. The gas detectors come pre calibrated and the signed calibration sheets shall be available Gas Detection Transmitters Description The gas detection element s installation location is not arbitrary and must be installed as per manufacturers recommendation specific to the gas. In most applications multiple detectors are used to monitor multiple zones. This is certainly the case for Wet Well and Dry Well. The gas level 4-20mA signal is read by the PLC for indication and trending, however 3 additional dry contacts are also available and configured as follows: - Device Fault ( fixed ) - 5% LEL - 10% LEL These digital signals are used for Alarming (Device Fault) and for hardwired interlocks, visual and audio indication. For process control details please review the process Control Narratives (PCN). Testing Procedure It is important to test the normal operation, as well as the abnormal circumstances or failures. In order to test the functionality of the device and the configuration, calibrating gas canisters of known concentrations are used. The testing procedure is described in the manufacturer provided manual and should be followed closely as these procedures vary somewhat from device to device. The Min/Max and engineering units must be configured correctly in the RPU, SCADA, Pressure transmitter, and they must correspond to the calibration sheet. Strachan Sewage Pumping Station Version 0.1 WSP Inc. Page 13 of 26

22 Normal Operation Under normal operation the LEL readings are very low, practically zero. It is critical that the configured range in the RPU/SCADA matches the range in the gas detector itself. To verify this, calibrating gas of known concentration is used as per the manufacturer instructions. It is critical that the local display, the OIT and HMI all correctly display the same values. Software generated alarms are triggered at 20% and 40% while hardware generated alarms (dry contacts) are generated at 5% and 10%. If an interlock/action/alarm is triggered (as described in the PCN) then this action is to be confirmed in the field and HMI/OIT. For all alarm conditions, ensure they are correctly reported in the Alarm Summery and Alarm Log (HMI and OIT). Abnormal Condition / Failure A dedicated digital contact is generated to indicted an internal fault is present. This signal is monitored by the RPU and indicated in the SCADA. Ensure correct indication (blinking) at both the HMI and the OIT. If an interlock/action/alarm is triggered (as described in the PCN) then this action is to be confirmed in the field and HMI/OIT. For all alarm conditions, ensure they are correctly reported in the Alarm Summery and Alarm Log (HMI and OIT). 1.5 Building (Security, Door Contacts and Smoke Detectors) In addition to process monitoring, building utilities and other devices are also monitored for trending, alarming and even control Door Contacts Description Door contacts are generally magnetic reed type. Where by a magnetic reed filament is used to open or close a contact in the presence of a magnet. These are sealed units with no adjustments other than the physical installation. In general the magnet is installed on the door or hatch while the switch is stationary. Other door switches also exist but the principal is similar: a dry contact is opened or closed when a door/hatch is opened or closed. The signal is monitored by the RPU for door status indication, alarming and logging. For process control details please review the process Control Narratives (PCN). Testing Procedure Door contacts are designed to detect if a door is NOT closed rather than if a door is opened. As such it is critical to test if the device was installed such way that the contact changes state as soon as the door is cracked open. As such, all doors and hatches must be opened slowly in order to detect the switching point and the indication on the HMI and OIT is correct. A security system is also programmed into the RPU which will generate an intrusion alarm if a disarm code is not entered by the operator within a prescribed period from when the door was first opened. Further a 4 hour countdown must begin from the moment the system is disarmed, once the countdown expires, the system is re-armed. The countdown timer duration shall be adjustable from the OIT between the acceptable range of 4 to 8 hours. Normal Operation It is expected that the functionality of the door switches (one at a time) as well as the security system is tested out fully and is in agreement with the PCN description. With the system armed, a door is opened and a 5 minute count down (operator adjustable depending on the station configuration) begins during which the operator must disarm the system from the OIT. If this time expires and the system was not successfully disarmed, an intrusion alarm is generated. The alarm is to be verified at HMI/OIT. For all alarm conditions, ensure they are correctly reported in the Alarm Summery and Alarm Log (HMI and OIT). Abnormal Condition / Failure Door switches cannot be monitored for fault, thus no abnormal condition can be tested. Strachan Sewage Pumping Station Version 0.1 WSP Inc. Page 14 of 26

23 1.5.2 Smoke Detectors Description Most common smoke detector is the ionizing type detector. The operating principal is that when smoke particles enter the ionizing chamber they allow the ionized oxygen and nitrogen particles to bind to them instead of being attracted to the detector plates in the chamber. This causes a change in the normal flow of ions and is detected by the electronics in the detector. The smoke detectors are distributed throughout the station by zones. Each detector is monitored by the RPU for alarm condition (a dry contact) for proper indication, alarming and logging in the OIT and HMI. For process control details please review the process Control Narratives (PCN). Testing Procedure It is critical that each smoke detector is tested individually and that the correct indication and alarm description is configured in the OIT and HMI. Each smoke detector alarm description in the alarm summery must be clear and indicate the location of the detector. Normal Operation Under normal condition the smoke detectors are not in alarm state, one by one, smoke should be introduced to trigger the smoke detectors and verify that the OIT/HMI and alarm summery are in agreement with the triggered detector. If an interlock/action/alarm is triggered (as described in the PCN) then this action is to be confirmed in the field and HMI/OIT. For all alarm conditions, ensure they are correctly reported in the Alarm Summery and Alarm Log (HMI and OIT). Abnormal Condition / Failure Smoke alarms cannot be monitored for fault, thus no abnormal condition can be tested. Strachan Sewage Pumping Station Version 0.1 WSP Inc. Page 15 of 26

24 Section 2 Purpose of Equipment and the Testing Procedure The following is a description of the devices, how they work, what their role is in this application, how they are to be tested and what the expectations are. 2.1 Heating Ventilation and Air Conditioning (HVAC) Ventilation is a critical component of the design as it is used to de-rate the area classification of the dry well. It is a safety system and not designed strictly for equipment protection and creature comfort. This section covers the heating, ventilation, and air conditioning (where applicable). Description The ventilation system comprises of supply fans or blowers as well as exhaust fans or blowers. The system is monitored and controlled by the PLC as well as hardwired interlocks. The Ventilation and HVAC system section of the PCN must be reviewed in conjunction with this testing procedure as the ventilation requirements between the wet well and dry well differ as well as ventilation requirements from station to station. Dry Well For the dry well the ventilation system is designed to maintain constant air exchanges in the dry well in order to de-rate an otherwise Div 1 Calss/Zone 2 area into an unclassified area. The NFPA820 requirements are that 6 air exchanges per hour are maintained in order to maintain the unclassified status. Since the ventilation system is designed to run continually it is designed to start automatically once the power it available (emergency power or utility power alike). In general (please review the PCN for station specifics), hardwired interlocks between the exhaust fan(s) and the associated damper(s) are as follows: - The exhaust fans have associated dampers which are interlocked to the fans. The interlock calls for the damper to open first, and only allow the motor to start once the damper is in the open position. - The damper s position is monitored by limit switches and a Fail to Open alarm is generated if the damper does not travel to the full open position within a predefined time (default 10 sec). A physical timer in the MCC cabinet is used for this function. - The supply fan does not have dampers nor is it interlocked to the exhaust fan in any way. Each fan is monitored by the RPU for the following alarm conditions: - Not Available - Fan Overload - No Flow (contact from flow switch) - Damper failed to open (one alarm per damper) For cooling and humidity control an air-conditioning (A/C) units are provided (Not all statio ns are equipped, please review the PCN for station specifics). The air conditioning units are a split type with an outdoor compressor unit and an indoor cassette complete with four registers and motorized swing vane operation. The air A/C units controlled based on the humidity readings in the dry well. The RPU will issue a start command on humidity readings above 75% (operator adjustable at OIT/HMI) and will continue to operate until the humidity level drops below 65% (operator adjustable). Further, the RPU will automatically start the A/C unit upon temperature readings above 28 C and stop when temperature drops below 25 C. For heating purposes unit heaters, installed throughout the station (Control Room, Pump Room, etc.), will automatically start and stop based on the temperature readings in that particular area and the user defined (at OIT/HMI) temperature set point (typically 18 C) and dead band (typically 2 C). Essentially the heaters will start when temperature drops below 18 C and stop once it reaches 20 C, however the set points (by area) is operator adjustable at the OIT/HMI. Strachan Sewage Pumping Station Version 0.1 WSP Inc. Page 16 of 26

25 Wet Well For the wet well, the ventilation system shall start automatically if the gas detectors register gas levels above a predetermined set point (hardwired interlocks). Further, the wet well ventilation can also be started based on wet well temperature via the RPU (the temperature set point is adjustable at OIT and HMI). The blower fans are equipped with a Hand-Off-Auto selector switch allowing the operator to either run the fans continually (Hand position) or prevent the fans from starting (Off position). However the normal position is Auto, and is a requirement for the above described control to function correctly. The Wet Well blower fans will be automatically commanded to run (hardwire interlock) on elevated LEL reading from the gas sensor (hardwired) or Occupied mode On (hardwired) of if the temperature in the wet well rises above 30 C (operator adjustable) (software interlock). It is important to note the following hardwired interlocks between the supply fans and exhaust fans as well as the associated dampers: - Each pair of supply and exhaust fan are interlocked such that the exhaust fan (master) is commanded to start and the supply fan (slave) starts automatically ba sed on the exhaust fan run contact. In this scenario, the exhaust starts first then the supply fans ensuring a slight negative pressure in the wet well during start up. It also ensures that positive pressure scenarios are eliminated. - Each fan has associated damper(s) which are interlocked to their parent fan. The interlock calls for the dampers to open first, and only allow the motor to start once the damper is in the open position. - The damper s position is monitored by limit switches and a Fail to Open alarm is generated if the damper does not travel to the full open position within a predefined time (default 10 sec). A physical timer in the MCC cabinet is used for this function. Each fan is monitored by the RPU for the following alarm conditions: - Not Available - Fan Overload - No Flow (contact from flow switch and run command) - Damper failed to open (one alarm per damper) - Auto Mode for all exhaust and supply fans (Not in Auto is an Alarm State) Temperature control in the wet well is control as follows: For cooling purposes a software interlock (as described above) will automatically start the ventilation fans and provide fresh outside air when the temperature rises above 30 C, the fans will continue to operate within the dead band (typically 2 C but operator adjustable). For heating purposes the two unit heaters installed in the upper wet well area will automatically start and stop based on the wet well temperature readings and the user defined (at OIT/HMI) temperature set point (typically 15 C) and dead band (ty pically 2 C). Essentially the heaters will start when temperature drops below 15 C and stops once it reaches 17 C, however the set points (by area) is operator adjustable at the OIT/HMI. Testing Procedure It is important to test the normal operation, as well as the abnormal circumstances or failures. Part of the testing procedure is to simulate fan/blower failure for each device. The alarms and interlocks are to be verified against the PCN description. Dry Well Supply Fan Ensure the Fan Not Available indication is correct on OIT/SCADA. Ensure the Fan Overload indication is correct on OIT/SCADA. Ensure the supply fan On/Off switch is operational and lockable in the On position. Ensure the fan starts and stops immediately on the switch position change respectively. Ensure the fan run status is indicated correctly at the OIT/SCADA. Ensure an Alarm is generated by the in duct flow switch under low flow or no flow conditions and that is annunciated correctly in the SCADA. (High Priority Alarm) Dry Well Exhaust Fan Strachan Sewage Pumping Station Version 0.1 WSP Inc. Page 17 of 26

26 Ensure the Fan Not Available indication is correct on OIT/SCADA. Ensure the Fan Overload indication is correct on OIT/SCADA. Ensure the exhaust fan Hand/Off/Auto switch is operational. In Hand the damper opens and then the fan starts immediately regardless of the supply fan status. In Off the damper closes and the fan stops. In Auto the damper opens or closes and the fan starts and stops based on the running status of the supply fan. Ensure the fan does not start until the damper opens. Ensure that if the damper does not reach the fully open position within the predetermined time, a failure to open alarm is triggered and indicated at the OIT/SCADA. Ensure the fan run status is indicated correctly at the OIT/SCADA. Ensure an Alarm is generated by the in duct flow switch under low flow or no flow conditions and that is annunciated correctly in the SCADA. (High Priority Alarm) Dry Well Temperature Control In order to test the temperature control it is required that the temperature set points be temporarily manipulated in each one of the areas (one at a time). Heating From the OIT, note the current temperature in any particular area. Using the OIT, reduce the temperature setpoint to half degree below the current temperature. The heater should be commanded to start and continue to operate until the temperature rises to 2 degrees (dead band) above the SP. Repeat for each area. Once an area is tested, return the setpoints to the original values. Cooling For the drywell the ventilation is continually running, thus unless the station is equipped with an A/C unit, no further cooling capabilities are available. However, where an A/C unit does exist, this functionality can be tested by lowering the upper temperature set point to 0.5 degrees below the current temperature in the drywell. The A/C unit shall start and continue to operate until the temperature drops to 2 degrees below the setpoint. The A/C unit can also be triggered using the humidity setpoint, proceed in a similar manner as the temperature test. Wet Well Temperature Control The wetwell temperature is also monitored and controlled of excessive heat. From the OIT, change the upper temperature setpoint in the wet well to two 0.5 degrees below the current wetwell temperature. The ventilation should start and continue to operate until the temperature drops to 2 degrees below the set point. Once all tests are complete ensure all setpoints are returned to the default values. 2.2 Motor Operated Valves and Knife Gates Description Typically motor operated valves (and knife gates) are not interlocked for automatic control, however there are exceptions such as pump discharge or suction isolation valves. This section describes a general testing procedure for the motor operated valves. It is the intent that the PCN is used to identify any and all interlocks associated with these valves, and these interlocks must be verified alongside of the valve testing. Testing Procedure All motor operated valves (MOVs) are fitted with a local controls and typically also remote controls. It is prudent to first test the Local controls before moving on to remote. Strachan Sewage Pumping Station Version 0.1 WSP Inc. Page 18 of 26

27 Local at Valve (Local) With the Local/Stop/Remote selector switch in the Local position, ensure the indication at OIT/SCADA match. Use the local push button or switch to open the valve and ensure the valve position indication at OIT/SCADA is correct. Next, use the local controls to close the valve and ensure the OIT/SCADA indication matches. Closed valves shall be Green colored, while Opened valves shall be Red colored. Ensure the valve faceplate opens and the valve status is displayed correctly (OIT/SCADA) and no remote control is possible. Local at Valve (Stop) With the Local/Stop/Remote selector switch at the valve in the Stop position, ensure the valve position and mode status is indicated correctly ( Actuator Local ) on the graphics and the faceplates (OIT/SCADA). Ensure no remote control is possible nor local remote from the Open/Close button or switch. Valve Control Panel at MCC With the Local/Stop/Remote selector switch at the valve in the Remote position and the Local/Remote switch at the Valve Control Panel in Local mode. Ensure the valve position and mode of operation indicated correctly and the valve faceplate indicates ( Control Panel Local ) at OIT/SCADA. Further ensure the valve operation from the control panel, and ensure no Remote operation is possible. Computer Auto With the Local/Stop/Remote selector switch at the valve in the Remote position and the Local/Remote switch at the Control Panel in the Remote position, ensure the valve position and mode status is indicated correctly ( Computer Auto ) on the graphics and faceplates (OIT/SCADA) and ensure remote manual operation functions correctly. Some valves may be fitted with further interlocks and may have a Remote Auto mode. This functionality must be tested and must correspond to the PCN. 2.3 Pumps Description The pump operation is the single most critical component of the automation system in the pump station. The pumps are the primary components while all others are support equipment. The main idea is that the pumps will start and stop in order to maintain minimal level of sewage in the wetwell since it s not practical to vary the flow of sewage out of the pump station all the way down to zero flow, a dead band type strategy is employed allowing the pumps to stop completely once the level drops and then allow the level to raise before restarting. This is done for a number of reasons the most critical being that a certain minimum flow rate (fluid veloc ity) through the forcemains is required in order to keep suspended solids suspended and prevent sanding (settling of solids on the bottom of the pipes). Multiple layers of redundancy is implemented in an effort to eliminate the possibility of overflowing or flooding as this equates to flooded basements, a situation that needs to be avoided at all cost. Under normal conditions the wetwell level is maintained by monitoring the wetwell level using the ultrasonic level transmitter. Based on predefined level setpoints (see PCN for exact set points) one or more pumps are started depending on the rate of sewage flow into the pump station. Clearly higher flows demand multiple pumps and longer run times while lower flows may require a single pump starting and stopping at longer intervals. The key concept is that the pump station can fulfill a range of inflow from very low to very high such as during wet weather events. Maintaining this functionality and flexibility during a number of unforeseen circumstances requires a complex control system; the most obvious is power failure as this can very well coincide with high flow event such as during a heavy storm. A diesel generator is used to provide power to the station during such an event, however it is critical that the pumps restart in a controlled manner once the emergency power (from the generator) becomes Strachan Sewage Pumping Station Version 0.1 WSP Inc. Page 19 of 26