Input Current Control; Freeze-Up Protection Control - Daikin FT25CV1A Service Manual

Si01-406
3.4

Input Current Control

Outline Detect an input current by the CT during the compressor is running, and set the frequency
upper limit from such input current.
In case of heat pump model, this control is the upper limit control function of the frequency
which takes priority of the lower limit of four way valve activating guarantee.
Detail The frequency control will be made within the following zones.
When a "stop current" continues for 2.5 seconds after entering the stop zone, the compressor
operation stops.
If a "drooping current" continues for 1.0 second after entering the drooping zone, the frequency
will be 2 Hz drooping.
Repeating the above drooping continues until the current enters the drooping zone without
change.
In the unchanged zone, the frequency limit will remain.
In the return / reset zone, the frequency limit will be cancelled.
Limitation of current drooping and stop value according to the outdoor air temperature
1. In case the operation mode is cooling
2. In case the operation mode is heating (only for heat pump model)
3.5

Freeze-up Protection Control

Outline During cooling operation, the signals being sent from the indoor unit allow the operating
frequency limitation and then prevent freezing of the indoor heat exchanger. (The signal from
the indoor unit must be divided into the zones as the followings.
Detail Conditions for Start Controlling
Judge the controlling start with the indoor heat exchanger temperature after 2 sec from
operation start.
Control in Each Zone
Functions and Control
The current droops when outdoor air temperature becomes higher than a certain level
(model by model).
The current droops when outdoor air temperature becomes higher than a certain level
(model by model).
Control for Heat Pump Models
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