JOHNSON CONTROLS
143
SECTION 2 – OPTIVIEW CONTROL CENTER
FORM 160.79-O3
ISSUE DATE: 11/09/2018
2
“CONTROL PANEL – POWER FAILURE”
A Control Power failure has occurred. If the power
failure duration was < the duration of the applicable
“Coastdown” period (2.5 minutes standard; 15 min-
utes steam turbine), the remainder of the “Coastdown”
is performed upon restoration of power. The chiller can
be started after the Operator presses the Clear Faults
button. This message can indicate a Cycling (auto-re-
start after power failure) or Safety (manual restart af-
ter power failure) shutdown, depending upon Control
Center configuration. It indicates a Cycling shutdown
when displayed in orange characters; Safety shutdown
when displayed in red characters. The Control center
is configured for auto-restart or manual restart after
power failure by a qualified Service technician.
“THRUST BEARING #1 – PROXIMITY PROBE
CLEARANCE”
The chiller (both compressors) has shutdown because
the clearance between Compressor #1 high speed
thrust collar and the tip of the proximity Probe has
increased > +10 mils (instantaneous) or decreased >
-25 mils (for 2 continuous seconds) from the Refer-
ence Position. The minimum allowed clearance is 23
mils. Therefore, if the Reference Position is < 47 mils,
the shutdown will occur when the actual position is
< 22 mils. The chiller cannot be started until the spe-
cial reset procedure is performed as referenced in the
CAUTION below.
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.
The clearance is only checked during the last 20 sec-
onds of “System Prelube”, during “System Run” and
during “Coastdown”. Therefore, the fault is only de-
tected during those periods. Also, the +10 mil thresh-
old must be exceeded for 2 continuous seconds.
“THRUST BEARING #2 – PROXIMITY PROBE
CLEARANCE”
The chiller (both compressors) has shutdown because
the clearance between Compressor #2 high speed
thrust collar and the tip of the proximity Probe has
increased > +10 mils (instantaneous) or decreased >
-25 mils (for 2 continuous seconds) from the Refer-
ence Position. The minimum allowed clearance is 23
mils. Therefore, if the Reference Position is < 47 mils,
the shutdown will occur when the actual position is
< 22 mils. The chiller cannot be started until the spe-
cial reset procedure is performed as referenced in the
CAUTION below.
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.
The clearance is only checked during the last 20 sec-
onds of “System Prelube”, during “System Run” and
during “Coastdown”. Therefore, the fault is only de-
tected during those periods. Also, the +10 mil thresh-
old must be exceeded for 2 continuous seconds (in-
stantaneous with previous software).
This shutdown must be evaluated by a
qualified Service Technician prior to
starting the chiller. Starting the chiller
without this evaluation could result in
severe compressor damage. To prevent the
chiller from starting without the proper
evaluation, restart is inhibited until the
clearance is within acceptable limits and a
special reset procedure is performed by the
Service Technician. The evaluation and
reset procedure are contained in Service
Manual (Form 160.69-M1-C).
