Protection Control
Mini UM S/M
46
Function
4.2
Low Pressure Protection Control
This low pressure protection control is used to protect compressors against the transient
decrease of low pressure.
[In cooling operation]
[In heating operation]
Pe
<0.25MPa
52Hz
Pe
>0.4MPa
Pe
<0.07MPa
Low pressure not limited
(V3175)
LP pressure sensor detection
value
Pe:
Low pressure
limited
Low pressure
standby
When occurring 3 times within 60 min.,
the malfunction code "E4" is output.
Pe
< 0.07MPa
(V3176)
&
&
SVP = OFF
SVP = ON
Pe>0.25MPa
INV upper limit
frequency
•
•
More than 124Hz
Pe<0.16MPa
Upper limit: 1-step up from
current compressor frequency
Upper limit:
124Hz
Upper limit:
52Hz
Low pressure not limited
Low pressure limited
Pe>0.19MPa(every 20 sec.)
Pe>0.17MPa
Pe<0.13MPa
Pe<0.13MPa
Pe<0.16MPa
Pe<0.10MPa
Pe>0.19MPa
LP pressure sensor detection
value
Pe:
Low pressure
standby
When occurring 3 times within 60 min.,
the malfunction code "E4" is output.
Mini UM.book Page 46 Monday, January 24, 2005 11:32 AM
