Kaisai 06RY1, Service Manual

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3. Check the +15V circuit according to corresponding wiring diagram. If IC4/5/6PIN12 on inverter module output voltage is not +15V means the inverter
module is failed. If voltage output of inverter module is +15V means main PCB is failed.
4. Check the bridge rectifier using one of the following two methods (refer to Figure 4-4.11):

Method 1: measure the resistance between any two of the 5 bridge rectifier terminals. If any of the resistances is close to zero, the bridge rectifier
has failed.

Method 2: dial a multimeter to the diode setting:
- Put the red probe on the DC power output negative terminal (terminal 5) and put the black probe onto each of the AC power input terminals
(terminals 1, 2 and 3) in turn. The voltage between terminal 5 and each of terminals 1, 2 and 3 should be around 0.378V. If the voltage is 0, the
bridge rectifier has failed.
- Put the red probe on the DC power output positive terminal (terminal 4), then put black probe onto each of the AC power input terminals
(terminals 1, 2 and 3) in turn. The voltage between terminal 4 and each of terminals 1, 2 and 3 should be infinite. If the voltage is 0, the bridge
rectifier has failed.
Figure 4-4.11: Bridge rectifier
Three phase AC power input
DC power output
Figure 4-4.10: P N +15V te15V
（
IC4/5/6PIN12
）；
N-
（
IC/4/5
、
6
）
PIN13
Schematic diagram
N
+15V
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L4 troubleshooting(the same as L1/L2) 4.21.8
Situation 1: L4 error appears immediately after the outdoor unit is powered-on
L4
Replace the inverter PCB
Condition 2: L4 error appears after the compressor has been running for a period of time and the compressor speed is
over 60rps
L4
Compressor is over-current
2
Yes
Replace the compressor
No
Replace the inverter PCB
Notes:
1. Re-start the unit, use clip-on ammeter to measure the compressor current, if the current is normal indicates the compressor is failed, if the current is
abnormal indicates the inverter PCB is failed..
L5/L8/L9 troubleshooting 4.21.9
L5/L8/L9
The wire is not connected properly
NO
Ensure wire is connected properly
Yes
Inverter module PCB has malfunctioned
Yes
Replace inverter module PCB
No
Replace the compressor
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