Delta M42U User Manual

Table 6-3D: Fault Codes & Messages
Message Possible cause Action
HW CT B Fail
(F43)
1. Test current loop is broken
2. CTP4 is defective
3. Detection circuit malfunction
HW CT C Fail
(F44)
1. Test current loop is broken
2. CTP5 is defective
3. Detection circuit malfunction
1. Large Grid harmonics
2. Switching device is defective
3. Detection circuit malfunction
1. Check the utility waveform. Grid connection
of inverter needs to be far away from
non-linear load if necessary
2. Check all switching devices in inverter
stage
3. Contact our customer service for
technical support
1. AFCI is not installed.
2. AFCI self-test is fail.
Check the AFCI detection circuit board to
insure proper connections
Contact customer service for technical
support
HW AC OCR
(F45)
AFCI Circuit
Fail
(F58)
One or more DC relays are
abnormal
Contact customer service for technical
support
HW DC RLY
(F76)
The inverter detects Arcing
occurs.
Check PV array cables for replacement
AFCI Fault
(F59)
DC Cur. High
(F60, F61,
F70, F71)
1. Switching device in boost
is defective
2. Driver for boost is defective
3. Input current detection
circuit malfunction
1. Check all switching device in boost
2. Check the driver circuit for boost inside
the inverter
3. Check input current detection circuit
Contact customer service for technical
support
Contact customer service for technical
support
91
Error message and Trouble Shooting

Delta M42U Specifications

General

Brand	Delta
Model	M42U
Category	Inverter
Language	English