YORK YK — LCSSS - Run signal

The control center displays LCSSS - Run signal as a cycling shutdown message; the shutdown tables also print it in capitals as LCSSS - RUN SIGNAL. Both spellings refer to the same shutdown of the liquid cooled solid state starter (LCSSS).

The LCSSS receives two start signals from the control center simultaneously: one through the serial communications link, and one through the start relay on the I/O board to TB6-24 in the control center. The hardware member of this pair is the 115 VAC start signal between J5-2 wire #2 and TB1-3 wire #24; the other is the software run signal sent through the serial communications link. The main system microprocessor must receive both signals within 5 seconds of each other. If they are not received within 5 seconds of one another, a cycling shutdown is performed and this message is displayed.

• 115 VAC not applied between J5-2 wire #2 and TB1-3 wire #24.
• Solder cracks around J5 and TB-1.
• A faulty serial communication link cable.

1. Verify that 115 VAC is present between J5-2 wire #2 and TB1-3 wire #24.
2. Inspect around J5 and TB-1 for solder cracks.
3. Check the serial communication link cable.

• Both start signals must arrive within 5 seconds of one another; this 5-second window is the threshold whose miss triggers the cycling shutdown.

The manual gives no separate reset procedure; it classifies the event as a cycling shutdown with the outcome: Cycling shutdown: automatic restart after coastdown if the shutdown is no longer active and the compressor switch is still in the run position. The unit therefore comes back on its own after coastdown once the shutdown is no longer active, as long as the compressor switch is still in the run position.