Danfoss AK-PC 551 - Compressor timers

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
Dene 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
Dene 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
Dene 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
Dene 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
Dene 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
Dene 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 dene 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 (congure the DI input via
“Conguration” 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