YK CENTRIFUGAL LIQUID CHILLER OptiView ... - Johnson Controls

The imbalance is not checked until the unit has been
running for at least 45 seconds and the average of the
three phases of motor current is > 80% of the
programmed 100% unit Full Load Amps.
The average is calculated as:
The imbalance is calculated as:
LCSSS - PHASE (X) SHORTED SCR
(Flash memory Card version C.MLM.01.04 or later)
A shorted SCR in phase A, B or C (designated as X in
the message) has been detected by the LCSSS
logic/trigger board. The voltage across each SCR in
monitored to detect the shorted condition. The shorted
condition must exist for 5 seconds in order to annunciate
the fault.
This check is disabled while the unit is running. The unit
can be started after the condition has been corrected
and the 'COMPRESSOR' switch is cycled to the
'STOP-RESET' (O) position.
LCSSS - OPEN SCR
Iave =
An open SCR has been detected by the LCSSS
logic/trigger board. The open condition must exist for 5
seconds in order to annunciate the fault. The unit can be
started after the condition has been corrected and the
'COMPRESSOR' switch is cycled to the 'STOP-RESET'
(O) position.
This check is disabled when the unit is shut down.
In certain applications, local power supply
conditions could interfere with the open SCR
detection technique. The check should be
disabled by a qualified Service Technician
using manual 160.54-M1.
LCSSS - PHASE ROTATION
(Ia+Ib+Ic)
3
(Ia-Iave) + (Ib-Iave) + (Ic-Iave)
2(Iave)
x 100
(Flash memory Card version C.MLM.01.04 or later)
The LCSSS logic/trigger board has detected the three
phase compressor motor supply voltage phase rotation
is not correct. The unit can be restarted when the phase
rotation is correct and the 'COMPRESSOR' switch is
cycled to the 'STOP-RESET' (O) position.
10.4.2 Safety Shutdown Messages Models with
Compressor Motor Variable Speed Drive
These messages are generated by events that occur
within the Variable Speed Drive (VSD). The unit can be
started after manual resets are performed as detailed
below.
Service and troubleshooting information is
contained in manual 160.00-M1.
VSD SHUTDOWN – REQUESTING FAULT DATA
The VSD has shut down the unit and the control panel
has not yet received the cause of the fault from the VSD,
via the serial communications link. The VSD shuts down
the unit by opening the motor controller 'VSD Stop
Contacts' (located on the VSD logic board and
connected between TB6-16 and TB6-53 in the control
panel).
The microprocessor board in the control panel then
sends a request for the cause of the fault to the VSD
logic board via the Adaptive Capacity Control (ACC)
board, over the serial link. Since serial communications
are initiated every 2seconds, this message is typically
displayed for a few seconds and then replaced with one
of the following fault messages.
VSD – STOP CONTACTS OPEN
160-54-OI-GB0 43
SEE ‘VSD SHUTDOWN – REQUESTING FAULT
DATA‘
If the microprocessor board in the control panel does
not receive the cause of the fault over the serial link
within 20 seconds, it is assumed it is not available and
that message is replaced with this message.
VSD – 105% MOTOR CURRENT OVERLOAD
This shutdown is generated by the VSD logic board and
it indicates that a motor overload has occurred. The
shutdown is generated when the VSD logic board has
detected that at least 1 of the 3 output phase currents
has exceeded 105% of the unit Full Load Amps (FLA)
value for > 7 seconds.
The unit FLA value is set by adjustment of the FLA
potentiometer on the VSD logic board. The unit can be
started after the 'RESET' push-button on the VSD logic
board is pressed and the 'COMPRESSOR' switch is
cycled to the 'STOP-RESET' (O) position.