
10 Troubleshooting
Troubleshooting in check mode
SMGB0091 rev.2 - 11/2015
266
Activating condition of protection control code
To monitor the conditions such as the temperature change and others, the control of the frequency and other controls are
performed by the protection control in order to prevent the abnormal operations. The activating conditions of protection
control are shown in the table below:
Code
Protection control
Activating condition
Remarks
P1
Pressure ratio control
Compression ratio ε ≥ 7.5 => frequency decrease
Compression ratio ε ≤ 1.6 => frequency increase
ε = (Pd+0.1)/(Ps+0.1)
P2
High-pressure increase protection
High pressure switch for control is activated
=> Frequency Decrease
-
P3
Inverter current protection
If Inverter PCB secondary current > (*1)A
=> Frequency decrease
-
P4
Inverter fin temperature increase
prevention
If inverter fin temperature is:
RASC-(4-6)HNPE ≥ 70 ºC
RASC-(8/10)HNPE ≥ 80 ºC
=> Frequency decrease
-
P5
Discharge gas temperature increase
protection
Temperature at the top of compressor is high
=> frequency decrease (Maximum temperature is
different depending on the frequency)
Temperature at the top of compressor > 112 ºC
=> Indicate P5
-
P9
High-pressure decrease protection
Discharge pressure of compressor decrease under
1.0 MPa => Frequency increase
Cooling operation and lowest
step fan or heating operation
pA
Demand current control (running
current limit control)
Compressor run current ≥ demand setting value
=> frequency decrease
Demand setting value: upper
limit of total running current is
set to 100%, 80%, 70%, 60%
at normal operation using
input on PCB1
Ps: Suction pressure of compressor (MPa)
Pd: Discharge pressure of compressor (MPa)
(1*)
Connection
3N~ 400V 50Hz
HP
4
5
6
8
10
Current (A)
11.0
11.0
11.0
17.5
20.0
?
N O T E
• During protection control (except during alarm stoppage), the protection control code is indicated.
• The protection control code is indicated during protection control and turns off when cancelling the protection control.
• After retry control, the condition of monitoring is continued for 30 minutes.