York YK-EP, Operation And Maintenance Manual

Page: 201 / 268

LCSSS – Phase Locked Loop
The Liquid Cooled Solid State Starter Logic/Trigger Board phase locked loop circuit was not able to
maintain lock with phase A of the power line. This could be caused by a power line anomaly such
as sag or jitter. A power line frequency jitter of up to 3 Hz/second can be tolerated. The chiller will
automatically restart when lock has resumed.
LCSSS – Low Supply Line Voltage
The Liquid Cooled Solid State Starter Logic/Trigger Board has detected that the compressor motor
AC Power Line Voltage, in any phase, decreased below the low line voltage threshold continuously
for 20 seconds. The chiller will automatically restart when the voltage in all phases returns to the
restart level. The thresholds are as follows:
Table 203: Voltage thresholds
Supply voltage
range (Volts)
Shutdown (Volts) Restart (Volts)
Disabled None N/A
200-208 160 174
220-240 185 200
380 305 331
400 320 349
415 335 362
440-480 370 400
550-600 460 502
LCSSS – High Supply Line Voltage
The Liquid Cooled Solid State Starter Logic/Trigger Board has detected that the compressor motor
AC Power Line Voltage, in any phase, exceeded the high line voltage threshold continuously for 20
seconds. The chiller will automatically restart when the voltage in all phases returns to the restart
level. The thresholds are as follows:
Table 204: Voltage thresholds
Supply voltage
range (Volts)
Shutdown (Volts) Restart (Volts)
Disabled None N/A
200-208 227 226
220-240 262 261
380 415 414
400 436 435
415 454 453
440-480 524 523
550-600 655 654
LCSSS – Logic Board Processor
Communication between the V25 Microprocessor and Digital Signal Processor (DSP) on the Liquid
Cooled Solid State Starter Logic/Trigger Board has been interrupted. The chiller will automatically
restart when communications are restored.
201 YK-EP Style B Centrifugal Chiller