AK-PC 551 User Guide RS8GY302 © Danfoss 2015-06 11
Comp. 1 min cap.
*: For scroll and CRII
Minimum capacity in the time period (without a minimum capacity the compressor
will not be cooled)
Min: 10%
Max: 50%
Fac: 10%
Comp. 1 start cap
*: For scroll and CRII
Start capacity: the compressor will only start when the capacity requirement reaches
the value
Min: 10%
Max: 60%
Fac: 30%
Comp. 1 Sd temp. *, **: For “Scroll”, “Stream” and CRII
Dene whether the controller should monitor the discharge gas temperature Sd from the
compressor (NTC 86K or Pt 1000 Ohm).
AI-demand
No / Yes
Fac: No
Comp. 1 Sd max. *, **: For Scroll, Stream, CRII and yes to “Comp.1 Sd temp”
Set the maximum Sd temperature
Min: 0°C
Max: 195°C
Fac: 125°C
No.of unloaders ****: For compressor with unloaders
Set how many unloaders there are on the compressor
DO-demand
Min: 1
Max: 3
Fac: 1
Comp. safety input Compressor safety circuit
Dene whether a DI input should be reserved for registration of each compressor safety
circuit
DI-demand
Yes /No
Fac: Yes
LP switch via DI Low pressure safety circuit
Dene whether a DI input should be reserved for registration of the signal from an LP switch
DI-demand
Yes /No
Fac: No
Load shedding via DI Load limitation
Dene whether a DI input should be reserved for registration of the signal from
a power meter
• None:
• DI: Load limitation must follow a DI input
• Night Mode: Load limitation must follow the status of the day/night signal.
(The day/night signal can be received via a DI input, via time schedule or network.)
DI-demand
Yes /No
Fac: No
Sd disch. gas temp. Shared discharge temperature
Dene whether signals from a common Sd sensor on the suction line (Pt 1000) should be
received
AI-demand
Yes /No
Fac: No
Ss suction superheat Monitoring of superheat
Dene whether a signal from a common Ss sensor on the suction line should be received
AI-demand
Yes /No
Fac: No
Injection ON fct. Stop injection into evaporators
If the compressors are prevented from starting, stop injection into the evaporators.
Here dene whether the function should be active and how the signal should be
communicated.
No: The function is not used
Network: The controller sends a signal to the system unit, which then forwards it to
the evaporator controls
Relay: The function reserves a relay that pulls in if all compressors are stopped.
All evaporator controls must be wired to this signal from the relay.
DO-demand
No /Network /Relay
Fac: No
Compressor timers Compressor timers
Lead comp. Min ON Min. On-time for rst compressor
Set a forced On-time here during which the compressor will remain in operation before it
can be switched o again. The setting is to prevent incorrect operation.
To prevent a compressor breakdown, the setting must be made in accordance with the
requirements of the compressor supplier.
Min: 0 min
Max: 60 min
Fac: 0 min
Lead comp. Min OFF Min. O-time for rst compressor
Set the forced O-time during which the compressor must be o before it can be switched
on again. The setting is to prevent incorrect operation.
Min: 0 min.
Max: 30 min
Fac: 0 min
Lead comp. Restart Min. period of time for re-starting the rst compressor.
Set the forced O-time during which the compressor must be o before it can be switched
on again. The setting is to prevent incorrect operation.
To prevent a compressor breakdown, the setting must be made in accordance with the
requirements of the compressor supplier.
Min: 1 min.
Max: 60 min
Fac: 4 min
Lead comp. Safety
delay
Delay time before compressor no. 1 cut out for reasons of safety
The time begins when a signal is received on the DI input (congure the DI input via
“Conguration” and “Comp. safety inlet”).
Min: 1 min.
Max: 10 min
Fac: 1 min
Comp. Min ON Min. On-time for remaining compressors
Set a forced On-time here during which the compressor will remain in operation before it
can be switched o again. The setting is to prevent incorrect operation.
Min: 0 min.
Max: 60 min
Fac: 0 min
Comp. Min OFF Min. O-time for remaining compressors
Set the forced O-time during which the compressor must be o before it can be switched
on again. The setting is to prevent incorrect operation.
Min: 0 min.
Max: 30 min
Fac: 0 min
Comp. Restart Min. period of time for restarting remaining compressors
Set the forced O-time during which the compressor must be o before it can be
switched on again. The setting is to prevent incorrect operation.
Min: 1 min.
Max: 60 min
Fac: 4 min