Protection Control; High Pressure Protection Control - Daikin RXYQ96PYDN Service Manual

SiUS34-801A_b

8. Protection Control

8.1

High Pressure Protection Control

This high pressure protection control is used to prevent the activation of protection devices due to
abnormal increase of high pressure and to protect compressors against the transient increase of
high pressure.
[In cooling operation]
Pc_max>503.15psi
When high
pressure is limited
Pc_max
>503.15psi
Pc_max
>514.75psi
VRVIII R-410A Heat Pump 60Hz
The following control is performed in the entire system.
Pc_max indicates the maximum value within the system.
Normal Operation
Upper limit
compressor step:
2-step down
After 10 sec.
Current step maintained
After 10 sec.
For multi units:
When STD compressor is in operation
STD compressor standby
When STD compressor stays stopped
52Hz+OFF (upper limit)
Upper limit compressor step=max (Max. Step)
Pc_max
>527.8psi
When occurring 3 times within
30 min., HPS is activated without high
High pressure
pressure standby, and the
standby
malfunction code [E3] is displayed.

Protection Control

Pc_max
<469.8psi
Upper limit
compressor step:
1-step up
After 15 sec.
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