Sterling 30RA010-055 manual •Cooler Pump Control CPC Configuration, OPT1 ON

Opened During Normal Operation Alarm will be generated and the machine will stop.

If the control detects the chilled water pump interlock open for 25 seconds after initially being closed, a T194 — Cooler Pump 1 Contacts Opened During Normal Operation Alert is generated and the unit is shut down.

If the control detects the chilled water flow switch circuit closed for at least 5 minutes with the pump output OFF, an A202 — Cooler Pump Interlock Closed When Pump is Off Alarm will be generated and the unit will not be allowed to start.

If the control detects that the chilled water pump auxiliary contacts are closed for at least 25 seconds while the pump is OFF, a T198 — Cooler Pump 1 Aux Contacts Closed While Pump Off Alert is generated. The chiller will not be allowed to start.

If the control starts a pump and the wrong interlock circuit closes for at least 20 seconds, an A189 — Cooler Pump and Aux Contact Input Miswire Alarm will be generated. The unit will be prevented from starting.

As part of a pump maintenance routine, the pump can be started to maintain lubrication of the pump seal. To utilize this function, Cooler Pmp Periodic Start (PM.P.S) [Configuration, UNIT] must be set to YES. This option is set to NO as the fac- tory default. With this feature enabled, if the pump is not oper- ating, it will be started and operated for 2 seconds starting at 14:00 hours. If the pump is operating, this routine is skipped. If the pump has failed and an Alarm/Alert condition is active, the pump will not start that day.

DUAL INTEGRAL PUMP CONTROL — With a dual inte- gral pump package, the following options must be configured:

•Cooler Pump Control (CPC) [Configuration, OPT1] ON.

•Cooler Pump 1 Enable (PM1E) [Configuration, UNIT]

YES

•Cooler Pump 2 Enable (PM2E) [Configuration, UNIT]

YES

Pump Start Selection is a field-configurable choice. Cooler Pump Select (PM.SL) [Configuration, UNIT] is factory de- faulted to 0 (Automatic). This value can be changed to 1 (Pump 1 Starts First) or 2 (Pump 2 Starts First). If PM.SL is 0 (Auto- matic), the pump selection is based on two criteria: the alert status of a pump and the operational hours on the pump. If a pump has an active Alert condition, it will not be considered for the lead pump. The pump with the lowest operational hours will be the lead pump. A pump is selected by the control to start and continues to be the lead pump until the Pump Changeover Hours (PM.DT) [Configuration, UNIT] is reached. The Lead Pump (LD.PM) [Run Status, VIEW] indicates the pump that has been selected as the lead pump: 1 (Pump 1), 2 (Pump 2), 3 (No Pump). The Pump Changeover Hours is factory defaulted to 500 hours. Regardless of the Cooler Pump Selection, any pump that has an active alert will not be allowed to start.

With the dual integral pump package, the Cooler Pump Starter will be energized when the machine is in an occupied period. As part of the factory-installed package, an auxiliary set of contacts is wired to the MBB to serve as Chilled Water Pump Interlock, one set for each pump to individual channels on the MBB. With a call for mechanical cooling, the specific pump interlock and flow switch are checked. If the circuits are closed, the machine starts its capacity routine. If Pump 1 starts and the auxiliary contact interlock does not close within 25 seconds of the ON command, a T190 – Cooler Pump 1 Aux Contacts Failed to Close at Start-Up Alert will be generated and the pump shut down. The unit will not be allowed to start. If the chilled water flow switch does not close within 1 minute, two alarms will be generated. A T192 – Cooler Pump 1 Failed to Provide Flow at Start-Up Alert and an A200 – Cooler Flow/ Interlock failed to close at Start-Up will be generated and chiller

will not be allowed to start. In either fault case listed above, Pump 2 will be commanded to start once Pump 1 has failed.

If Pump 2 starts and the auxiliary contact interlock does not close within 25 seconds of the ON command, a T191 — Cooler Pump 2 Aux Contacts Failed to Close at Start-Up Alert will be generated and the pump shut down. The unit will not be allowed to start. If the chilled water flow switch does not close within one (1) minute, two alarms will be generated. A T193

—Cooler Pump 2 Failed to Provide Flow at Start-Up Alert and an A200 – Cooler Flow/Interlock failed to close at Start-Up will be generated and chiller will not be allowed to start. In either fault case listed above, Pump 1 will be commanded to start once Pump 2 has failed.

If the chilled water flow switch opens for at least 3 seconds after initially being closed, a T196 — Flow Lost While Pump 1 Running Alert or T197 — Flow Lost While Pump 2 Running Alert for the appropriate pump and an A201 — Cooler Flow/ Interlock Contacts Opened During Normal Operation Alarm will be generated and the machine will stop. If available, the other pump will be started. If flow is proven, the machine will be allowed to restart.

If the chilled water pump interlock opens for 25 seconds after initially being closed is detected by the control, the appro- priate T194 – Cooler Pump 1 Contacts Opened During Normal Operation Alert or T195 – Cooler Pump 2 Contacts Opened During Normal Operation Alert is generated and the unit is shut down. If available, the other pump will be started. If flow is proven, the machine will be allowed to restart.

If the control detects that the chilled water flow switch circuit is closed for at least 5 minutes with the pump output OFF, an A202 – Cooler Pump Interlock Closed When Pump is Off Alarm will be generated and the unit will not be allowed to start.

If the control detects that the chilled water pump auxiliary contacts are closed for at least 25 seconds while the pump is OFF, the appropriate T198 – Cooler Pump 1 Aux Contacts Closed While Pump Off or Alert T199 – Cooler Pump 2 Aux Contacts Closed While Pump Off Alert is generated. The chiller will not be allowed to start.

If the control starts a pump and the wrong interlock circuit closes for at least 20 seconds, an A189 – Cooler Pump and Aux Contact Input Miswire Alarm will be generated. The unit will be prevented from starting.

The control will allow for pump changeover. Two methods will change the pump sequence. Before the changeover can occur, the unit must be at Capacity Stage 0. During changeover the chilled water flow switch input is ignored for 10 seconds to avoid a nuisance alarm.

With Cooler Pump Select (PM.SL) [Configuration, UNIT] set to 0 (Automatic) and when the differential time limit Pump Changeover Hours (PM.DT) [Configuration, UNIT] is reached, the lead pump will be turned OFF. Approximately one (1) sec- ond later, the lag pump will start. Manual changeover can be ac- complished by changing Rotate Cooler Pump Now (ROT.P) [Configuration, UNIT] to YES only if the machine is at Capac- ity Stage 0 and the differential time limit Pump Changeover Hours (PM.DT) [Configuration, UNIT] is reached. If the PM.DT is not satisfied, the changeover will not occur. With the machine at Capacity Stage 0, the pumps would rotate automati- cally as part of the normal routine.

With Cooler Pump Select (PM.SL) [Configuration, UNIT] set to 1 (Pump 1 Starts First) or 2 (Pump 2 Starts First), a manual changeover can be accomplished by changing PM.SL only. The machine Remote-Off-Enable Switch must be in the OFF posi- tion to change this variable. The Rotate Cooler Pump Now (ROT.P) [Configuration, UNIT] feature does not work for these configuration options.

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