T2400h UPS won't switch on...?

[Chris Stoneley]

I have two T2400h UPS that now for some reason will not switch on. The battery boxes in both cases show a slight charge and I've checked the line input voltage is 220V and well within range; I've also tried tripping the 10A input circuit breaker on the back - to no avail. Anyone seen this issue before and know how to fix? At 100lbs total weight they are too heavy to ship anywhere for repar.