Daikin FTX25JVEA9, Руководство по обслуживанию

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System control Si18-201
134 Main Functions
3.16.2 Input Current Control II (High Pressure Control)
Outline Based on the input current and input voltage, the compressor output frequency is regulated to
decrease the compressor capacity in order to prevent abnormal rising of the high pressure.
Note The peak-cut control is similar to this function, but it cannot effectively detect high pressure
during transitional condition due to the thermistor's tracing performance; therefore, the high
pressure can increase abnormally in some cases. This function droops the compressor when a
transitional condition occurs or the high pressure rises suddenly in order to prevent abnormal
rising of the high pressure.
Therefore, the function start area is set higher that the high pressure setting of the peak-cut
control.
The high pressure saturation temperature is estimated from the power consumption (input
voltage, input current), output frequency and suction pressure, and three zones (reset, no-
change and drooping zones). When the high pressure saturation temperature is in one of the
zone, the output frequency limit is varied depending on the type of the zone.
Details The high pressure is estimated based on the high pressure estimation function (operating
frequency, input current, suction pressure), and the estimated high pressure is used to obtain
the saturation temperature. When the heat exchanger intermediate temperature enters the
overcooling zone, if the peak-cut control does not function, this function prevents abnormal
rising of the high pressure.
Cooling
Heating
A change of 2 Hz is made when each zone fluctuates.
The reset zone is set for 30 sec when compressor operation is started, for 30 sec when the
number of operating room units increase, and for 2 sec when the number of operating room
units decrease.
With each operation of the HPS operation counter, the zone judgement temperature is
decreased by 2°C.
Drooping speed : 2Hz/40sec
Reset zone
No-change zone
Drooping zone
58˚C
60˚C
62˚C
Target temperature
of liquid pipe
temperature rise
in cooling SC
control : 60˚C
(M1023)
Drooping speed : 2Hz/40sec
Reset zone
No-change zone
Drooping zone
56˚C
58˚C
60˚C
(M1024)