Protection Control
4.4
Inverter Protection Control
Inverter current protection control and inverter fin temperature control are performed to prevent
tripping due to a malfunction, or transient inverter overcurrent, and fin temperature increase.
[Inverter overcurrent protection control]
Invertercurrent >13.5A
INV upper limit frequency: 1-step down
from current compressor frequency
Invertercurrent > 13.5A
[Inverter fin temperature control]
Tfin>84˚C
INV upper limit frequency: 1-step /
1 min down from current compressor
frequency
Tfin>84˚C
72
In the case of multi-outdoor-unit system, each INV compressor performs these controls in
the following sequence.
Nomal operation
Inverter current < 13.5A
&
INV upper limit frequency = 210 Hz
Under inverter current
protection control
Inverter current > 15.0A continues for 260 sec.
Inverter current standby
Nomal operation
&
Under fin temperature
protection control
Tfin>98˚C
Fin temp. standby
Inverter current<13.5A continues
for 20 sec. or more.
INV upper limit frequency: 1-step up from
current compressor frequency
• When occurring 4 times within 60 min.,
the malfunction code "L8 " is output.
Tfin<81˚C
INV upper limit frequency = 210 Hz
Inverter current<81˚C continues
for 3 min. or more.
INV upper limit frequency: 1-step / 1 min
up from current compressor frequency
Interval
• When occurring 4 times within 60 min.,
the malfunction code "L4" is output.
Si39-502A
Function