28
7. Frequency
release
control
High pressure release control
This function is to correct the operation command of the compressor and suppress the
rise of high pressure.
1)Control contents
The operation frequency is decreased by 1 step when PD pressure 3.4 MPa.
It is decreased by 1 step every 10 seconds until PD pressure drops below 3.4 MPa.
2)Release condition
When PD pressure 3.2 MPa
When refrigerant recovery control starts in all heating mode
During defrost operation, stop, thermostat OFF.
8. A3-IPDU
control
IPDU controls inverter compressor by issuing commands relating to compressor
speeds, speed increases / decreases, and current release control values via the
interface P.C. board.
The main control functions of the IPDU P.C. board are described below.
1. Current release control
To prevent inverter input current from exceeding the specified value, output
frequency is controlled with AC input current as detected by T611 mounted on the
A3-IPDU P.C. board.
Current control values for various outdoor units are shown below.
Item
Description of operation, numerical data, and other information
Remarks
Zone A: Compressor is operated normally.
Zone D: The current operating frequency is maintained.
Zone B: Operating frequency is lowered.
Zone C: The lowering of operating frequency is halted
to maintain the current frequency.
Current
Zone B
Zone D
Zone C
Zone A
I
1
I
2
Outdoor unit
HP capacity
23.5A
23.0A
26.5A
26.0A
4
5
28.0A
27.5A
6
33
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2016/04/08 17:20:31
