Danfoss AK-CH 650 User Manual

AK-CH 650 Capacity controller RS8ER302 © Danfoss 2016-02 3
Application
AK-CH 650 is a water chiller control for capacity control of
compressors and air-cooled condensers on indirect refrigeration
systems within commercial refrigeration.
In addition to capacity control, the controller can control pumps,
injection signals to heat exchangers, defrosting sequences and
safety monitoring, etc.
The controller uses the following signals for control/monitoring:
S4 Charge temperature (control signal)
S3 Return temperature
Ss Suction gas temperature
Sd Discharge gas temperature
Po Suction pressure (frost-proong).
Pc: Condensing pressure
S7 Return temperature for any hot brine
Sc3 Ambient temperature
Compressor capacity is controlled by charge temperature S4 and
by suction pressure P0 as frost protection. Condenser capacity is
controlled by condensing pressure Pc or, alternatively, tempera-
ture sensor S7.
1. Introduction
Among the dierent functions are:
- Capacity control of up to 6 compressors (max. 3 unloads/comp)
– Relay output, which is activated by a request for extra cooling
- Speed control of one or two compressors
- Up to 6 safety inputs for each compressor
- Capacity limitation to minimize consumption peaks
- Twin pump control with automatic operating time equalisation
- Start/stop signal for heat exchanger injection, incl. pump down
function
- Defrost control with time or temperature stop
- Liquid injection into suction line
- Safety monitoring of high pressure / low pressure / discharge
temperature
- Frost protection
- Capacity control of up to 8 fans
- Floating condenser reference with regard to outside temperature
- Heat recovery function
- Fan capacity with regard to Step coupling, speed regulation or a
combination
- Safety monitoring of fans
- Alarm signals can be generated directly from the controller and
via data communication
- Alarms are shown with texts so that the cause of the alarm is
easy to see.
- Plus some completely separate functions that are totally inde-
pendent of the regulation – such as alarm inputs, thermostats,
pressostat and voltage inputs.
Example
If the condenser end needs full control of a dry refrigeration
circuit, AK-CH 650 can be combined with a type AK-PC 420 dry
refrigeration control.
SW = 2.0x

Danfoss AK-CH 650 Specifications

General

Brand	Danfoss
Model	AK-CH 650
Category	Controller
Language	English