YORK YK — LCSSS - High supply line voltage

The display reads LCSSS - High supply line voltage. In the control center's list of cycling shutdown messages the same event is printed as LCSSS - HIGH SUPPLY LINE VOLTAGE.

The LCSSS logic/trigger board monitors the compressor motor AC power line voltage. The chiller shuts down when the phase-to-phase RMS input voltage in any phase stays above the high supply limit set for the programmed voltage range for 20 continuous seconds; in the 440-480 V range, for example, the limit is 524 V while running and 523 V stopped. The protection is disabled for the first 20 seconds of the starter run, and it is disabled entirely if no voltage range is programmed.

• The wrong voltage range is selected on the OptiView™ control center.
• Improper line voltage is applied to the starter.

1. Verify that the voltage range selected on the OptiView™ control center is the proper one for the supply.
2. Confirm the line voltage that is being applied to the starter.

The shutdown and restart levels follow the supply voltage range programmed at the control center:

• 200 to 208 V — shutdown at 227 V, restart at 226 V
• 220 to 240 V — shutdown at 262 V, restart at 261 V
• 380 V — shutdown at 415 V, restart at 414 V
• 400 V — shutdown at 436 V, restart at 435 V
• 415 V — shutdown at 454 V, restart at 453 V
• 440 to 480 V — shutdown at 524 V, restart at 523 V
• 550 to 600 V — shutdown at 655 V, restart at 654 V
• Disabled — no shutdown or restart threshold applies

This is a cycling shutdown. The chiller automatically restarts once the voltage in all phases returns to the restart level. After the coastdown period — 150 seconds for centrifugal chillers — it restarts if the shutdown is no longer active and the compressor switch is still in the run position.