Troubleshooting guide
MAGNUM VERSION 8 MANUAL REVISION 3.1
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# of Cond ROs –Total number of Relay Outputs of each compressor, in this example there are 3. The number of fans
in each compressor does not have to be the same.
Starting Condenser RO – The starting condenser Relay Output. All the Relay Outputs specified for each circuit must
follow consecutively to this point. In this example CND FAN 1 is the starting Relay Output for circuit 1 and the other 2
fans follow consecutively in the RO screen.
Condenser Fan AO - If a condenser fan AO was specified in this cell it would function as described in the example in
section 7.74.3.6 RO Step Common with a Fan AO and Condenser Faults. There is no condenser fan AO in this
example.
Starting Condenser Fault - If there were condenser faults specified in this cell they would function as described in the
example in section 7.74.3.6 RO Step Common with a Fan AO and Condenser Faults. There are no condenser faults in
this example.
# Cond Faults – Total number of Condenser Faults.
Cond Fan Bank – In this type of condenser all compressors should have a different fan bank.
Each compressor fan bank is controlled individually. The discharge pressure for each compressor is used to control
condenser logic.
7.74.3.8. RO Step Combined
The RO Step Combined has a bank of fans that are shared by two consecutive circuits. The number and location of
the fans are specified in the Circuit Base screen. This is similar to the RO Step Individual set up except only every
other compressor has a condenser fans associated with it.
Circuit 1 and 2 will share the same fan bank specified in the ‘Cond Fan Bank’ cell. Circuit 3 and 4 will also share the
same fan bank specified. The highest discharge pressure between the two compressors on each respective circuit will
be used as the control pressure for their fan bank.
Condenser Faults
If any of these digital inputs are ON for the time specified in Setpoint #90 if active, then both compressors sharing that
condenser will we will be locked out and an alarm message will be generated. This example has no condenser faults.