SECTION 3 - DISPLAY MESSAGES
JOHNSON CONTROLS
181
FORM 160.87-OM1
ISSUE DATE: 8/24/2018
3
LCSSS – Phase (X) Shorted SCR
A shorted Silicon Controlled Rectifier (SCR) in phase
A, B or C (designated as X in the message) has been de-
tected by the Liquid Cooled Solid State Starter Logic/
Trigger Board. The voltage across each SCR in moni-
tored to detect the shorted condition. The shorted con-
dition must exist continuously for 5 seconds in order to
annunciate the fault. This check is disabled while the
chiller is running. The chiller can be started after the
condition has been corrected and the Operator presses
the WARNING RESET button.
LCSSS – Open SCR
An open Silicon Controlled Rectifier (SCR) has been
detected by the Liquid Cooled Solid State Starter Log-
ic/Trigger Board. The open condition must exist con-
tinuously for 5 seconds in order to annunciate the fault.
The chiller can be started after the condition has been
corrected and the Operator presses the WARNING
RESET button. This check is disabled when the chiller
is shut down. In certain applications, local power line
conditions could interfere with the open SCR detection
technique. This requires a qualified Service Technician
to disable this check. Refer to
OptiView Control Center
– Service Instructions (Form 160.54-M1).
LCSSS – Phase (X) Open SCR
An open SCR in phase A, B or C (designated as X
in message) has been detected. This safety shutdown
has the same criteria as LCSSS – OPEN SCR above,
however, the phase in which the open SCR occurred is
identified.
LCSSS – Phase Rotation
The Liquid Cooled Solid State Starter Logic/Trigger
Board has detected the three phase compressor motor
power line voltage phase rotation is not correct. The
chiller can be started after the phase rotation is correct
and the Operator presses the WARNING RESET but-
ton.
COMPRESSOR MOTOR VARIABLE SPEED
DRIVE: SAFETY SHUTDOWN MESSAGES
The following safety shutdown messages are displayed
on Compressor Motor Variable Speed Drive (VSD)
applications only. These messages are generated by
events that occur within the VSD. The chiller can be
started after manual resets are performed as detailed
below. Service and troubleshooting information is con-
tained in
Variable Speed Drive – Service Instructions
(Form 160.00-M1)
.
VSD Shutdown – Requesting Fault Data
The VSD has shut down the chiller and the Control
Center has not yet received the cause of the fault from
the VSD, via the serial communications link. The VSD
shuts down the chiller 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 Center). The Microboard in the Control Center
then sends a request for the cause of the fault to the
VSD Logic Board via the Adaptive Capacity Control
Board, over the serial link. Since serial communica-
tions are initiated every 2 seconds, this message is typ-
ically displayed for a few seconds and then replaced
with one of the following fault messages.
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 chiller Full Load Amps
(FLA) value for greater than 7 seconds. The chiller
FLA value is set by adjustment of the FLA potenti-
ometer on the VSD Logic Board. The chiller can be
started after the RESET push-button on the VSD Logic
Board is pressed and the Operator presses the WARN-
ING RESET button.
VSD – High Phase A Inverter Heatsink Tem-
perature
(Style D VSD)
This shutdown will occur if the heatsink temperature
exceeds 158°F on any of the output pole assemblies.
This shutdown will seldom occur. In most cases where
the coolant temperature has risen abnormally, the VSD
will shut down on Ambient Temperature @ 140.0°F
before the heatsinks can reach 158°F. If this message
is displayed, make sure there is adequate coolant level,
ascertain the pump is operating when the chiller is run-
ning, and check the strainer in the primary of the heat
exchanger for clogs and silt. The chiller can be start-
ed after the fault condition clears, the RESET button
on the VSD Logic Board is pressed and the Operator
presses the WARNING RESET button.
VSD – High Phase B Inverter Heatsink
Temperature
(Style D VSD)
See PHASE A message above.
