Danfoss ADAP-KOOL AK-PC 783, Руководство по конструкции, Страница: 34 / 128

34 Capacity controller RS8GN202 © Danfoss 11-2013 AK-PC 783
Design of a compressor and condenser control
Procedure:
1. Make a sketch of the system in question
2. Check that the controller’s functions cover the required
application
3. Consider the connections to be made
4. Use the planning table. / Note down the number of connections
./ add up
5. Are there enough connections on the controller module? – If
not, can they be obtained by changing an ON/OFF input signal
from voltage signal to contact signal, or will an extension
module be required?
6. Decide which extension modules are to be used
7. Check that the limitations are observed
8. Calculate the total length of modules
9. The modules are linked together
10. The connection sites are established
11. Draw a connection diagram or a key diagram
12. Size of supply voltage/transformer
1
Sketch
2
Compressor and condenser functions
AK-PC 783
Application
Regulation of a compressor groups on MT and LT x
Regulation of a condenser groups on MT x
Regulation of a cascade heat exchanger x
Regulation of compressor capacity
Control sensor = P0 x
PI-regulation x
Max. number of compressors
4 MT+ 4 LT
5 MT + 3 LT
Max. number of unloaders each compressor 3
Identical compressor capacities x
Different compressor capacities x
Speed regulation of 1 or 2 compressors x
Run time equalisation x
Min. restart time x
Min. On-time x
Liquid injection in suction line x
Liquid injection in cascade heat exchanger x
Liquid injection in screw compressor x
External start/stop of compressors x
Make a sketch of the system in question.
Follow these 12
steps
Oil management
Oil injection in compressor. Shared or individual x
Receiver pressure control x
Monitoring of oil level in receiver x
Management of oil level in oil separator x
Reset of oil management x
Cutout of compressors at oil failure x
Safety relays during forced compressor control x
Suction pressure reference
Override via P0 optimization x
Override via “night setback” x
Override via "0 -10 V signal" x
Regulation of condenser capacity
Control sensor = PcMT x
Step regulation x
Max. number of steps 8
Speed regulation x
Step and speed regulation x
Speed regulation first step x