York YK-EP Operation And Maintenance Manual page 198

Table 199: Manual and automatic shutdown resets
Device Manual reset fault
Overload
CM-2 Module
Overload
High Temp (more than 212°F)
Solid State Starter
Fault Current
Motor Controller – Loss Of Current
The Compressor Motor current decreased to 10% Full Load Amps (FLA) for 25 continuous seconds
while the chiller was running. This could be caused by the starter de-energizing during run or a
defect in the motor current feedback circuitry to the Control Center. The chiller will automatically
restart at the completion of System Coastdown.
Power Fault
The CM-2 Current Module (Electro-Mechanical Starter applications) or Solid State Starter Logic
Board (Mod "A" Solid State Starter applications) has shutdown the chiller because it detected a
fault condition that places the motor at risk. These devices open and close the Motor Controller
"CM" contacts (located on the respective device and connected between TB6-16 and TB6-53 in the
Control Center) in less than 3 seconds to initiate the shutdown and produce this message. An LED
on the respective device illuminates to identify the specific fault that has occurred. Refer to Solid
State Starter (Mod "A") – Operation and Maintenance (Form 160.46-OM3.1) for details of Solid State
Starter initiated shutdowns and OptiView Control Center – Service Instructions (Form 160.54-M1) for
CM-2 initiated shutdowns. The chiller will automatically restart when the contacts close.
Table 200: Device shutdown
Device
CM-2 Module
Solid State Starter
Control Panel – Schedule
The programmed Daily Schedule Setpoint has shutdown the chiller. If this occurs while the chiller is
running, the Pre-Rotation Vanes are driven fully closed prior to shutting down the chiller. The chiller
will automatically restart at the next scheduled start time.
Starter – Low Supply Line Voltage (Mod "A" Solid State Starter)
The voltage in any phase of the AC Power Line Voltage supplying the Solid State Starter has
decreased to the low line voltage threshold for 20 continuous seconds. The chiller will automatically
restart when the voltage returns to the restart level. The thresholds are as follows:
Table 201: Voltage thresholds
Supply voltage
range (Volts)
380
400
415
198
Shutdown
Power Fault
Power Fault
Half Phase
Shutdown Restart
(volts) (volts)
305 331
320 349
335 362
Automatic reset fault
None
Phase Rotation/Loss
High Temp start inhibit (more than 110°F)
Trigger Board Out-of-Lock
YK-EP Style B Centrifugal Chiller