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10
Technical
brochure RC8CF102 © Danfoss 08-2014
AK-PC
551
Example: Application
Application: Digital scroll
The configuration and daily operation of the AK-PC 551 will be
explained via an application example:
AK-PC 551 controls a refrigeration system with two suction
groups of compressors and a common air cooled condenser�
Refrigerant: R404A
Suction group MT:
1 digital scroll compressor
2 single step scroll compressors
Control according to suction pressure Po
Set point -15 °C
Monitoring of discharge temperature of digital scroll
Suction group LT:
2 single step scroll compressors
Control according to suction pressure Po
Set point -30°C
Condenser:
Speed control of 4 fans
Common safety monitoring of fans
Relay output for start/stop of VSD
Control according to condensing pressure Pc
Floating reference according to Sc3 outdoor temp�