AUX ASW-H09B5B4/FAR3DI-C3, Service Manual

Page: 60 / 101

57
(26) P8–Overcurrent Protection
Explanation of
error
Cause: Controller detects AC bus current exceeding the set protection
value, then limits and reduces the frequency.
Inspection path: system blockage
→
grid voltage
→
outdoor unit
controller
Tools required
for inspection
Multimeter, pressure gauge
Frequent
problematic part
Grid voltage and outdoor unit controller
Inspection
procedure and
key points
1. Use a mutlimeter to detect and check if the bus voltage is too low,
causing the overcurrent protection.
2. Use a pressure gauge to check whether the pressure of the system
exceeds the standard. If the pressure exceeds the standard, it may lead
to dirty blockage of the system.
3. Replace the outdoor unit controller and if the unit returns to normal,
it is the problem of the controller.
Special attention
Generally, such protection occurs at high load, but should not occur at
low load and low temperature, and the priority of this protection is
after the protection of refrigeration against overload and exhaust.