York 160.87-OM1, Operation And Maintenance Manual

Page: 214 / 268

Watchdog – Software Reboot
The Microboard’s software Watchdog initiated a Microprocessor reset because it detected that a
portion of the chiller operating program was not being executed. The result of this reset is a safety
shutdown and re-initialization of the program. This is generally indicative of a severe electrical
power disturbance or impending Microboard Failure. The chiller can be started after the Operator
presses the WARNING RESET button.
Surge Protection – Excess Surge
(Applies only if Surge Protection Shutdown feature is Enabled)
The Surge Window Count surge events exceeded the Count Limit Setpoint. If the Surge Protection
Extended Run feature is Disabled, the chiller shuts down as soon as the count exceeds the limit. If
the Extended Run feature is Enabled, this shutdown occurs only if the count exceeds the limit at
completion of the 10 minute Extended Run period. The chiller can be started after the Operator
presses the WARNING RESET button.
Motor – Lack of Bearing Lubrication
The Operating Hours Since Last Motor Lubrication has exceeded set hours. This message replaces
WARNING MOTOR BEARING LUBE REQUIRED above. This safety shutdown remains in effect until
the Operator presses the WARNING RESET button and enters his/her initials, name or user ID in
OPERATOR access level (or higher) using the MOTOR LUBE ACKNOWLEDGE key on the MOTOR
LUBRICATION Screen. Refer to the Motor lubrication screen for entry instructions. The date and
time of this entry is automatically logged as the Date Of Last Motor Lubrication and Time Of Last
Motor Lubrication. It also resets the Operating Hours Since Last Lubrication to zero.
The date this warning occurs is stored as the Date Of Last Motor Lubrication Warning Or Fault.
This message will only be displayed if the Auto Lube Setpoint is disabled. With this setting, if the
Shutdown Setpoint is enabled, this safety shutdown will occur. If shutdown is disabled, this warning
message will be displayed but the safety shutdown will not be performed.
Motor – High Winding Temperature
This safety shutdown occurs when either of the following conditions are present:
• Any of the enabled Motor Winding Temperatures exceeded the programmed High Winding
Temperature Shutdown threshold plus the programmed Winding Hotspot Allowance
threshold for 3 continuous seconds.
-OR-
• The Average Winding Temperature has exceeded the programmed High Winding
Temperature Shutdown threshold for 3 continuous seconds.
The values programmed for the above safety thresholds are displayed as High Winding
Temperature Shutdown and Winding Hotspot Allowance on the MOTOR SETPOINTS Screen. They
are programmed with the Winding Setup Setpoint on that screen. The chiller can be started after
all winding temperatures decrease to at least 18°F (10°C) below the shutdown threshold and
the Operator presses the WARNING RESET button. This safety shutdown will not occur when the
Winding Temperature Protection Setpoint is set to Disabled on the MOTOR DETAILS Screen. Also,
it will not act on any RTD input registering as an open RTD or any individual winding temperature
sensor that has been disabled with the Temperature Disable Setpoint on the MOTOR SETPOINTS
Screen.
YK-EP Style B Centrifugal Chiller 214