EBME Forums Forums Maintenance Technical Assistance xray system LISTEM REX650R Troubleshooting

If somebody can provide help, for x-ray LISTEM REX650R, I have no STATUS LEDs light on HT CONTROL BOARD up after powering system (especially POWER ON LED),
many Thanks,

I don't know this machine, Hamid ... but by the sound of it there is a power supply voltage missing somewhere.

Any other clues? Interruption of mains power supply? Some sort of physical damage? Was the machine working OK before? No error codes, I suppose?

What fault finding have you done so far?

It started with two blown fuses at the main power 220vac, now replaced and all ac and dc voltages (+-12,+5 vdc) seems to be ok, but we haven't schematics !... before, this machine was perfectly running since 2009 ! first issue !...

Blown main fuses? Must have been a short circuit somewhere, then.

That sort of thing usually means something "burned". No sign of anything like that?

What's the present status? Same as given in your first post?

Meanwhile, do you think this machine has any mains voltage compensation on the input side? Has it been "adjusted" (incorrectly, perhaps) - or maybe it's automatic (and now faulty, jammed etc.). Take a look around where the power comes into the machine.

Traditionally, the "line voltage adaptor" was usually found (circuit-wise) immediately after the main input fuses (and before the main auto-transformer).

Im sure your IGBT is shorted causing the fuse to blown..

Does this machine use them?

And if so ... failure of IGBT's is often "catastrophic" (and therefore should be apparent just by looking at - or sniffing - them)!

If they are now open circuit ... how was the failure caused; over-voltage, inductive kick-back - or something else?

.. sometime over use.