inverter repairs

[urbantuckerman]

Hi, we have a seven year old boy, and 12v power. unfortunately this has led to two inverters being connected backwards over the years and both are now broken (we have others!). Both blew fuses when connected wrongly but on replacing the fuses the inverters appear to work normally, until you put them under load, when the low battery alarm goes off. Does anyone have any idea what could be wrong with them? it´s probably only one component, and its a shame to chuck them if they can be repaired!

Any and all help greatly appreciated!

p.s. we only get to town once a week to use the public internet in the library, so we´ll be a while replying to posts!

[dave45]

I had a faulty inverter last year... no-one was interested in repairing it. The makers (Trace) were most unhelpful, and wouldn't supply a circuit diagram for me to have a go myself. (I did anyway and failed!) As is the norm these days they only want you to buy a new one.

When I used to repair electronic stuff, I found that a good rule of thumb was to look for the most expensive component and replace it. The cheap components are the survivors ! but that was in the days before surface-mounted bits... if I was to guess I'd say it would be one or more of the power transistors/FETs... these are usually about 1cm x 1cm x 3mm, with 3 legs and are attached to a large metal heat-sink... sometimes they can be very difficult to extract, and may have insulating kits that are easy to damage

beware - my opinion may not be worth much as I am a dabbler rather than an electronic engineer!

[urbantuckerman]

thanks for your reply i ll pass it on to my boyfriend. We ve not been in town for a few weeks hence the late reply