EN/07.2013/58/63
In all other conditions, the evaporator fan runs at full speed limited by the value:
M92 + (M93 - M92) * (Free cooling position) / 100
When the parameter M158 is set to YES, the parameter M51 is set to 0 (only by damper) and TI > (S01 + 1°C), then the
evaporator fans status control is a proportional integral (PI) type. When TI < S01 the evaporator fans speed is set to M90.
To enable this function, the parameter M166 must be set to a value greater than zero.
This control uses as regulation parameter (M166 - (TI -TM)). The band is set by parameter M167 while the integral time
is set by parameter M168.
The evaporator fans speed is in any case limited by the value:
M92 + ((M93 - M92)*x) / 100
When parameter M158 is set to YES, the evaporator fans are switched off only when the Danfoss compressor is effectively
OFF (data point Modbus 40301 equal to 0).
When parameter M158 is set to YES and the heater is on, the evaporator fans speed is set to M91.
4.11. Control under high external/internal temperature
The parameters involved are:
• M116 VALUE FOR HIGH INT. TEMPER. MODE ENABLE: pre-set = 35°C
• M117 VALUE FOR HIGH EXT. TEMPER. MODE ENABLE: pre-set = 50°C
• M118 VALUE FOR HIGH EXT. TEMPER. MODE DISABLE: pre-set = 10°C
When the compressor is on and:
– TAE > M117 or TI > M116 °C ---> evaporator fan speed under anti-freezing control
– TAE < (M117 - M118) ---> evaporator fan speed control (as described in par. 4.10) and TI < (M116 -1) °C
4.12. Hot start function
The parameters involved are:
• S11 ALARM LIMIT HIGH TEMPERATURE: pre-set = 40°C
• S12 HYSTERESIS OF HIGH TEMPERATURE ALARM: pre-set = 5°C
• M158 ENABLE DANFOSS COMPRESSOR: pre-set = NO
• M172 MINIMUM INTERNAL TEMPERATURE FOR HOT START FUNCTION: pre-set = 50 °C
• M173 MINIMUM EXTERNAL TEMPERATURE FOR HOT START FUNCTION: pre-set = 45 °C
The “hot start” function is enabled when parameter M158 is set to YES.
When TI > M172 and TAE > M173 then the Danfoss compressor speed is forced to 20%, until TI < (S11 - S12) and the
electrostatic valve is forced to 25% for a time equal to 90 seconds.
4.13. Control under high tc (or pc) (adaptive control)
The parameters involved are:
• M90 MinSpeed (Min Ve Speed)
• M112 TcMaxVe (Tc Value for Max Ve Speed)
• M113 TcMinVe (Tc Value for Min Ve Speed)
• M158 ENABLE DANFOSS COMPRESSOR :pre-set = NO
When the compressor is on and the Tc is over the M112 value, then the Ve speed is limited with the following formula:
New Speed = Speed - (Tc - TcMaxVe)*(Speed - MinSpeed) / (TcMaxVe - TcMinVe);
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