Inverter issue with DC short circuit

[M55]

Hi guys.

I need some help.

I have a 3000w 12v inverter. I lent it to a friend and now it doesn't switch on. I opened it and saw all 6 of the 40amp fuses were blown so I replaced them all. Now when I connect the battery to the inverter, there is a huge constant spark at the battery terminals like a short circuit.

what could the problem be? Please give some suggestions

[SunEagle]

Hi guys.

I need some help.

I have a 3000w 12v inverter. I lent it to a friend and now it doesn't switch on. I opened it and saw all 6 of the 40amp fuses were blown so I replaced them all. Now when I connect the battery to the inverter, there is a huge constant spark at the battery terminals like a short circuit.

what could the problem be? Please give some suggestions

It sounds like the fuses weren't the only parts that failed. If there are sparks at the battery then my guess is the inverter is shorted out somewhere and should not be used. I would try to get your friend to replace the inverter.

[M55]

Thanks for the reply.

Could I ask..is it possible that it blew because he may have connected it to the battery in reverse. Like by connecting the positive cord to the negative battery terminal?

[RichardCullip]

This is where you find out how good a friend he is.....

[SunEagle]

Thanks for the reply.

Could I ask..is it possible that it blew because he may have connected it to the battery in reverse. Like by connecting the positive cord to the negative battery terminal?

Depends on where in the circuit are those fuses. Usually they are in the Load end but if a couple are in the Line side it is possible your friend connected the inverter up incorrectly.

[M55]

Could i send a picture of the inside of the inverter? I would like to try and repair it instead of buying another one

[SunEagle]

Could i send a picture of the inside of the inverter? I would like to try and repair it instead of buying another one

A picture may show the issue but IMO you will need to check each component with an ohm meter to see if it is shorted or something else.

[M55]

Picture seems to not want to upload. However, there are 6 transformers inside and next to each one is a fuse.

[bcroe]

You may have blown the main switching transistors. If you need to ask us,
you are outside your expertise. Bruce Roe