York YK-EP, Operation And Maintenance Manual

Page: 200 / 268

same message, if the Liquid Cooled Solid State Starter does not receive a response from the Control
Center after 10 consecutive attempts to communicate with the Control Center after Initialization
has been successfully completed. The Control Center attempts to establish communications until
successful.
LCSSS Shutdown – Requesting Fault Data...
The Liquid Cooled State Starter Logic/Trigger Board has shut down the chiller but the Control
Center has not yet received the cause of the fault from the LCSSS, via the serial communications
link. The LCSSS shuts down the chiller by opening the Motor Controller LCSSS Stop Contacts (K1
relay located on the starter Logic/Trigger Board and connected between TB6-16 and TB6-53 in the
Control Center). The Microboard, in the Control Center then sends a request for the cause of the
fault to the Logic/Trigger Board over the serial communications link. Since serial communications
are initiated every 2 seconds, this message is typically displayed for a few seconds and then
replaced with one of the following fault messages.
LCSSS – Stop Contacts Open
Refer to LCSSS Shutdown – Requesting Fault Data . If the Control Center’s Microboard does not receive
the cause of a starter initiated shutdown with 20 seconds of the shutdown, it is assumed it is not
forthcoming and that message is replaced with this message. The chiller can be started when the
Motor Controller LCSSS Stop Contacts close.
A missing interlock jumper between Starter Logic/ Trigger Board J1-1 and J1-12 will also produce
this message.
LCSSS – Power Fault
The Liquid Cooled Solid State Starter Logic/Trigger Board has detected that the compressor motor
current in one or more phases has decreased to less than 10% of the FLA for a minimum of 1 line
cycle. This check is inhibited during the first 4 seconds of System Run and until the motor current
is greater than 25% of the Job FLA. The chiller will automatically restart upon completion of System
Coastdown.
LCSSS – Low Phase (X) Temperature Sensor
The Liquid Cooled Solid State Starter Logic/Trigger Board has detected that the temperature of the
starter phase A, B or C (designated as X in the message) Silicon Controlled Rectifier (SCR) Module
has decreased to less than 37°F. This would generally be indicative of a disconnected or defective
sensor. If all three SCR Modules are indicating a temperature of less than 37°F, the SCR Module
cooling pump turns on. This is accomplished by disconnecting all three sensors. This feature allows
Service Technicians to run the cooling pump while filling the cooling system by disconnecting plugs
P2, P3 and P4 in the LCSSS.
LCSSS – Run Signal
The Liquid Cooled Solid State Starter receives two start signals from the Control Center
simultaneously; one via the serial communications link and one via the start relay TB6-24 in the
Control Center. If they are not received within 5 seconds of one another, a cycling shutdown is
performed and this message is displayed. This is generally indicative of defective wiring.
LCSSS – Invalid Current Scale Selection
There is an invalid compressor motor current scale jumper combination installed in the Liquid
Cooled Solid Starter Logic/Trigger Board J1. Jumper combination determines allowable “100% FLA”
setpoint range; 7L-35 to 260A, 14L-65 to 510A, 26L-125 to 850A and 33L-215 to 1050A. The chiller will
be permitted to start when the jumpers are configured correctly. Refer to Solid State Starter (Mod
“B”) – Operation and Maintenance (Form 160.00-O2) for valid jumper configurations.
YK-EP Style B Centrifugal Chiller 200