JOHNSON CONTROLS
136
FORM 160.79-O3
ISSUE DATE: 11/09/2018
SECTION 2 – OPTIVIEW CONTROL CENTER
and reclosure of the motor starter. When it detects this
condition, the Power Fault LED on the CM-2 board
illuminates and the board’s CM contacts open and au-
tomatically reclose in less than 3 seconds to initiate the
shutdown. The LED will remain illuminated until the
Reset button on the CM-2 board is pressed. The chiller
will automatically restart when at the completion of
“Coastdown”.
“MOTOR CONTROLLER #2 – POWER FAULT”
A motor controller protection device has shutdown the
chiller (both compressors). Normally closed contacts
of locally installed external motor protection devices
(connected between TB6-15 and TB6-54) and the nor-
mally closed “CM” contacts of CM-2 Board #2 (con-
nected between TB6-54 and TB6-82) form a safety cir-
cuit in series with the starter run signal. If any of these
contacts open and reclose in less than 3 seconds, this
shutdown is initiated. The CM-2 board opens its con-
tacts and recloses them in less than 3 seconds when it
detects a motor current Power Fault condition on mo-
tor #2. A Power Fault condition occurs when the motor
current drops below 10% FLA. This protects against
potential compressor damage due to rapid opening
and reclosure of the motor starter. When it detects this
condition, the Power Fault LED on the CM-2 board
illuminates and the board’s CM contacts open and au-
tomatically reclose in less than 3 seconds to initiate the
shutdown. The LED will remain illuminated until the
Reset button on the CM-2 board is pressed. The chiller
will automatically restart when at the completion of
“Coastdown”.
“LEAVING CHILLED LIQUID – LOW TEM-
PERATURE”
The chiller (both compressors) has shutdown because
the leaving Chilled Liquid Temperature has decreased
to the programmed Shutdown Temperature Setpoint.
If the chiller is running when this occurs, the Pre-rota-
tion Vanes on the running compressors are driven fully
closed prior to shutting down the chiller. The chiller will
automatically restart when the temperature increases to
the programmed Restart Temperature Setpoint.
“CONTROL PANEL – SCHEDULE”
The programmed Daily Schedule Setpoint has shut-
down the chiller (both compressors). If the Chiller is
running when this occurs, the Pre-rotation Vanes on
the running compressors are driven fully closed prior
to shutting down the chiller. The chiller will automati-
cally restart at the next scheduled start time.
“OIL PUMP #1 – DRIVE CONTACTS OPEN”
The Oil Pump Variable Speed Drive for compressor #1
has shutdown the chiller (both compressors). It initi-
ates this shutdown by opening its status contacts con-
nected to the I/O Board TB3-70. The drive initiates a
shutdown anytime its internal protection circuits will
not permit the Drive to run. The contacts remain open
until its internal protection circuits are satisfied and
any applicable manual resets are performed. Refer to
YORK Variable Speed Oil Pump Drive Service Manual
160.52-M2
.
If compressor #1 is locked out using the Lockout key
on the Capacity Compressor Cycling Screen, this fault
does not cause compressor #2 to shutdown or prevent
it from starting. When this fault occurs on a locked-out
compressor, it is displayed as a warning. This allows
the user to know that a fault exists on the locked-out
compressor. The condition must be corrected prior to
the lockout being removed from the compressor. If it
is not, the warning condition will revert back to a shut-
down as soon as the lockout is removed and will cause
the chiller to trip.
“OIL PUMP #2 – DRIVE CONTACTS OPEN”
The Oil Pump Variable Speed Drive for compressor #2
has shutdown the chiller (both compressors). It initi-
ates this shutdown by opening its status contacts con-
nected to the I/O Board TB3-71. The drive initiates a
shutdown anytime its internal protection circuits will
not permit the Drive to run. The contacts remain open
until its internal protection circuits are satisfied and
any applicable manual resets are performed. Refer to
YORK Variable Speed Oil Pump Drive Service Manual
160.52-M2
.
If compressor #2 is locked out using the Lockout key
on the Capacity Compressor Cycling Screen, this fault
does not cause compressor #1 to shutdown or prevent
it from starting. When this fault occurs on a locked-out
compressor, it is displayed as a warning. This allows
the user to know that a fault exists on the locked-out
compressor. The condition must be corrected prior to
the lockout being removed from the compressor. If it
is not, the warning condition will revert back to a shut-
down as soon as the lockout is removed and will cause
the chiller to trip.