HeliosII-485MCP off grid solar inverter has no vac output and the error code is DCBUS-L

HeliosII-485MCP off grid solar inverter has no vac output and the error code is DCBUS-L

Model

HeliosII-485MCP off grid solar inverter


Description

Inverter has no AC output and the error code is DCBUS-L.




Analysis of the possibility of the cause

Customer connected on the output other voltage engine generstor.


Solutions and steps

Check:
As illustrated in above image, the place marked by red box is the actual location of IPM module. The four points within the red ellipse are the points we need to measure. 
Measurement procedures: measure  IPM module-using  multimeter,  and discharge white capacitance at first.



1. Use black probe to connect 0 point, and use red probe to connect 1, 2, 3 point respectively. The value of measurement should be more than 500 normally.




2. Change black probe and red probe connection points, use red probe to connect 0 point, and using black probe respectively connect 1, 2, 3 point, the value should be 1, under normal condition as shown below. In another words, exceeding multimeter’s measurement range. 



If check all display 0V, means AC output part Mosfet (IPM Module) damaged.


Solutions:

1. Send back to factory to check.

2. Change the Mosfet.