Inputs And Setpoints - Emerson MultiFlex CUB-II Installation And Operation Manual

is a large amount of information on a CUB status
screen, status information is grouped on this
screen in several groups of related information in
order to make the screen easier to read. These
groups are described below.

7.2.1. Inputs and Setpoints

All the major control inputs for a CUB and
the control setpoints are grouped together in the
left side column of the screen.
Case Temp 1-6
The Case Temp fields numbered 1 through 6
show the current value of the case discharge air
temperature sensors. If unused, NONE will be
displayed in the field instead of a temperature
value.
Safety Mode
The Safety Mode field will display whether
the board has any active alarms or failures. If the
system is functioning normally, this field will
show OK. If there is a failure, it will display one
of the Safety mode messages. Refer to Section
6.5., Alarm Conditions (Safety Modes) for more
information about Safety modes.
• OK - No Safety mode failures.
• Phase Fail - A phase loss has been detected and all
systems have been shut down.
• Oil Fail - The compressor has failed due to low oil
pressure.
• Hi Disch Trip - Discharge pressure rose higher than
the discharge trip setpoint, causing refrigeration to
shut down.
• Proof Fail - A compressor proof fail has occurred.
• Door Open Time - The door switch has been open
for longer than the programmed alarm time.
• Clean Time - The clean switch has been ON for lon-
ger than the programmed alarm time.
Control Type
For reference, Control Type shows whether
this CUB is controlling the compressor based on
the suction pressure or case temperature.
24 • MultiFlex CUB-II and CUB-TD I&O Guide
Control Temp
If you are using the Temperature strategy to
control the compressor, the Control Temp field
will show the current temperature value. You can
compare this value to the temperature setpoint
below it to determine if the compressor is sup-
posed to be ON or OFF.
Temp Setpoint
This field shows the current case tempera-
ture control setpoint, which is used in compres-
sor control when using the Temperature strategy.
Suction press
This field shows the current suction pressure
in the CUB. Note that if using the Pressure
compressor control strategy, this is the control
input for the compressor, which you can com-
pare to the Cut In/Cut Out setpoints below it on
the screen to determine if the compressor is sup-
posed to be ON or OFF.
Min SP
This field shows the value of the Minimum
Suction Pressure setpoint, which is used to shut
the compressor OFF before the suction pressure
can become too low. Min SP is used for Temper-
ature Control or Pump Down.
Cut In and Cut Out
The Cut In/Cut Out setpoints are used to turn
the compressor ON and OFF when the CUB is
operating under the Pressure compressor control
strategy. They are also used as fallback setpoints
when the control temperature source fails under
the Temperature strategy.
Disch temp
This field shows the current discharge tem-
perature sensor if defined as one of the 16 CUB
inputs.
Disch press
This field shows the current discharge pres-
sure in the CUB.
Oil press
This field shows the current oil pressure in
the CUB.
026-1705 Rev 7 06-APR-2010