32
Capacity
controller RS8HF102 © Danfoss 2017-07
AK-PC 772A
2
AK-PC
772A
Application
Regulation of a compressor group MT
x
Regulation of a condenser group LT
x
Regulation of a parallel compression IT
x
Regulation of a gas cooler
x
Regulation of CO2 receiver pressure
x
Regulation of compressor capacity
Regulation sensor = P0
x
PI-regulation
x
Max. number of compressor steps on MT + IT
3
Max. number of compressor steps on LT
2
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
External start/stop of compressors
x
Oil management
Oil equalisation
x
Suction pressure reference
Override via P0 optimization
x
Override via “night setback”
x
Override via "0 -10 V signal"
x
Regulation of gas cooler
Regulation sensor = Sgc
x
Step regulation
x
Max. number of steps
4
Speed regulation
x
Step and speed regulation
x
Speed regulation first step
x
Limitation of speed during night operation
x
Heat recovery function for domestic water or room
x
Gas cooler pressure reference
Floating pressure reference
x
Setting of references for heat recovery functions
x
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
Follow these 12
steps
Make a sketch of the system in question.
Compressor and condenser functions