Danfoss AK-PC 351 User Manual page 13

Fan mode
Control type
VSD Start speed
VSD Min speed
Fan status
Fan speed
Fan 1 status
Fan 2.....
Safety monitoring
Po/S4 Min limit
Po/S4 Max alarm
Po/S4 Max delay
Pc max limit
Tc Max limit
S7 max limit
Pc/S7 Max delay
Safety restart time
Sensor alarm reset
AK-PC 351
Configuration of fans:
Fan speed & DO: Speed controled fans via AO2 and start/stop via DO output.
Fan speed: Speed controlled fans via AO2
4 Fan step: step-by-step . Start/stop via 4 pcs. DO outputs
3 Fan step: step-by-step . Start/stop via 3 pcs. DO outputs
2 Fan step: step-by-step . Start/stop via 2 pcs. DO outputs
1 Fan step: step-by-step . Start/stop via 1 pcs. DO outputs
Not used
For step-by-step connection, the fans cut in and out sequentially (e.g. 123-321).
Normally, PI-regulation is used, but this can be changed to a P-regulation if the design of the
system necessitates this.
• PI Ctrl: Regulation is carried out here with as little deviation between the reference and
measurement as possible.
• P-band ctrl: Capacity is cut in here after proportional regulation.
Set the start speed of the frequency converter here.
The value must be higher than the VSD min. speed value.
Set the minimum speed of the frequency converter here.
If lower capacity is required, this minimum speed should be maintained untill the required
capacity reach 0%. Hereafter all fans stops completely
Fan status
Here a reading of the actually condenser fan capacity in % (speed control)
The status of Step 1 (step 1 or relay for frequency transformer) is indicated here
The status of Step 2, 3, etc. is indicated here
Safety limits for min. Po
If a low value is registered, all compressors will cut out
Alarm limit for high Po
If a high value is registered, an alarm will be generated
Delay time for issuing a Po max. alarm
Safety limit for max. Pc
If Pc exceeds the value set here minus 3 K, the entire condenser capacity will cut in,
and compressor capacity will be reduced by 1/3 for every 30 seconds.
If Pc exceeds the threshold value, the entire compressor capacity will immediately cut out,
and an alarm will be generated when the delay time expires.
Safety limit for max. Tc
The setting for PC max. limit, converted to temperature, can be read here.
Safety limit for S7
If S7 exceeds the value set here minus 3 K, the entire condenser capacity will cut in,
and compressor capacity will be reduced by 1/3 for every 30 seconds.
If S7 exceeds the threshold value, the entire compressor capacity will immediately cut out,
and an alarm will be generated when the delay time expires.
Time delay for Pc max. alarm
The alarm will only be generated when the time delay has elapsed.
Delayed start-up following safety cut-out
If a safety cut-out has occurred due to "Pc max. limit" or "Po min. limit",
the compressors must be kept stopped for a defined period of time. The amount of
time can be set here.
Reset alarm after sensor error
When a sensor error has occurred, an O.K. signal must be registered within a specified
number of minutes before the controller resets the alarm. The regulation will be resumed
as soon as the sensor signal is O.K.
User Guide RS8GZ302 © Danfoss 2015-06
DO-demand
AO-demand
Fac: Fan speed&DO
P / PI
Fac: PI
Min: 0%
Max: 40%
Fac: 20%
Min: 0%
Max: 40%
Fac: 10%
Min: -120°C (-1.0 bar)
Max: 30°C (159 bar)
Fac: -40°C (0.5 bar)
Min: -30°C (-1.0 bar)
Max: 100°C (159 bar)
Fac: 100°C (5.0 bar)
Min: 0 min.
Max: 240 min.
Fac: 5 min.
Min: -1 bar
Max: 159 bar
Fac: 40 bar
-
Min: -50°C
Max: 100°C
Fac: 100°C
Min: 0 min.
Max: 240 min.
Fac: 0 min.
Min: 0 min.
Max: 60 min.
Fac: 1 min.
Min: 0 min.
Max: 30 min.
Fac: 10 min.
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