JOHNSON CONTROLS
247
SECTION 8 - MICROPANEL
FORM 201.23-NM2
ISSUE DATE: 3/9/2015
8
when its oil temperature rises above 225°F. The system
will be inhibited from starting if the oil temperature is
above 175°F. The Status display fault message for this
safety is shown below:
SYS X YYYYYYYY HIGH OIL TEMP
X indicates the system and YYYYYYY indicates the
system is in a “FAULT” condition and will restart when
the fault clears or “LOCKOUT” and will not restart un-
til the operator clears the fault using the keypad.
Low Suction Superheat Cutout Fault
The Low Suction Superheat Cutout helps protect the
compressor from liquid floodback due to low suction
superheat. This safety is ignored for the first 30 sec-
onds of compressor operation. Low suction superheat
will fault a system when any one of the following con-
ditions occur:
• After the rst30 seconds ofrun time, ifthe suc-
tion superheat falls below 2.0°F, the discharge su-
perheat is less than 15°F, and the run time is less
than 5 minutes, the superheat safety will be ignored
for the next 30 seconds followed by setting the su-
perheat cutout to 0°F and linearly ramping it up
to 2.0°F over the next 60 seconds. If at any time
during these 60 seconds the suction superheat falls
below the ramped cutout, the system will fault and
shut down with a controlled ramped shutdown.
• If the suction superheat less than 2°F, the dis-
charge superheat less than 15°F for 10 seconds,
and the run time is equal to or more than 5 min-
utes, the system will fault and shutdown with a
controlled ramped shutdown.
• If the suction superheat less than 0.5°F and dis-
charge superheat is more than 15°F for 60 seconds
and run time equal to or more than 5 minutes, the
system will fault and shutdown with a controlled
ramped shutdown.
• If suction superheat less than 5°F for 10 minutes,
the system will fault and shutdown with a con-
trolled ramped shutdown.
The Status display fault message for this safety is
shown below:
SYS X YYYYYYYY LOW SUCTION SUPERHEAT
X indicates the system and YYYYYYYY indicates the
system is “FAULT” and will restart after the 120 sec-
ond anti-recycle timer times out or “LOCKOUT” and
will not restart until the operator clears the fault.
Low Discharge Superheat Cutout Fault
The Low Discharge Superheat Cutout helps protect the
compressor primarily from liquid floodback through
the economizer line due to a high flash tank level. It
also provides protection from liquid floodback through
the suction line in conjunction with the low superheat
safety. This safety is ignored for the first 5 minutes of
compressor operation.
After the first 5 minutes of run time, if the discharge
superheat falls below 10.0°F for 5 minutes, the sys-
tem will fault and shut down with a controlled ramped
shutdown.
The Status display fault message for this safety is
shown below:
SYS X YYYYYYYY LOW DISCHARGE SUPERHEAT
X indicates the system and YYYYYYY indicates the
system is in a “FAULT” condition and will restart when
the 120 second anti-recycle timer times out or “LOCK-
OUT” and will not restart until the operator clears the
fault using the keypad.
Sensor Failure Cutout Fault
The Sensor Failure Cutout prevents the system from
running when a critical sensor (transducer, level sen-
sor, or motor winding temp sensor) is not function-
ing properly and reading out of range. This safety is
checked at start-up and will prevent the system from
running if one of the sensors has failed.
The sensor failure safety will also fault and shutdown
a system while in operation, if a safety threshold is ex-
ceeded or a sensor reads out of range (high or low).
Following is the Status display fault message.
SYS X YYYYYYYY SENSOR FAILURE:
ZZZZZZZZZZZZ
X indicates the specic system. YYYYYYYY
will either indicate the system is in a
“FAULT” condition and will restart when
the fault clears, or “LOCKOUT” after 3
faults and will not restart until the opera-
tor clears the fault using the keypad.
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