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Heat pump controller RS8GF202 © Danfoss 2015-08
AK-HP 780
• ON/OFF signal for start/stop of speed regulation
• Alarm relay
• On/off signals from general thermostats (1-5), pressure switches
(1-5) or voltage input functions (1-5).
• Oil valves
• Safety relays for cutouts of compressors at oil failure
Solid state outputs
The solid state outputs on the controller module may be used
for the same functions as those mentioned under “relay outputs”.
(The output will always be “OFF” when the controller has a power
failure).
Analog output
• Speed regulation of pump.
• Speed regulation of the compressor
Compressor Group
• Refrigerant CO2 (R744)
• 4 only compressors with "Best fit". Speed control of one.
• Safety monitoring of each compressor
• Common high-pressure monitoring
• Sctrl setting 60°C, Night setback of 5 K
• Oil management of each compressor
• Pulse reset for stopped compressor (lack of oil)
Receiver
• Pump with speed control
• S7 reference 40°C
Oil Receiver:
• Monitoring of liquid level
• Control of pressure in oil receiver
Fan in plant room
• Thermostat control of fan in engine room
Safety functions:
• Monitoring of P0, Pd, Sd and superheat in suction line
• P0 max = 10°C, P0 min = -2°C
• Pd max = 50 °C
• Sd max = 120°C
• SH min = 5 °C, SH max = 35 °C
• Monitoring of low and high level in oil receiver
Other:
• Alarm output used
• External main switch used
Data from this example is used on the next page.
The result is that the following modules should be used:
• AK-HP 780 controller
• AK-XM 102B digital input module
• AK-XM 205B input and output module
• AK-OB 110 analog extension module
Example
