Last week my dcs system (1 tiu/ 3aiu) stopped. The Z4000 breaker popped and I'm unable to find a short anywhere.I then discovered no output through any channels in the tiu,even at the bench. It's a Rev L. All 4 fuses appear intact but no juice passes to the outputs. I've read all previous posts on the subject on the forum,but to no avail. Any help would be appreciated.Thanks a lot.
you probably had one of the 4 diodes that are on the input n output for your tiu shorted. check across the red n black terminals on the tiu meter set for ohms and you'll probably find a direst short.
they can be replaced by an asc tech , or if you know how to solder you can replace them yourself. do you know how to use a vom volt ohm meter?
I do. I'm also a pretty good solderer. Just not so familiar with circuit board and tiu anatomy.
ok here is a picture of the tiu inside the tvs diodes are marked TVS if I were you I would change all 4 of them chances are if one is damaged chances are the other 3 could go anytime since they may have been shocked from a voltage spike ! ok
you can purchase the tvs diodes from digikey electronics 1.5ke36ca
if you need other help feel free to ask!
I'll give it a go, but would the diodes short out without the 20amp fuses blowing?
Do the TVS replacements have a polarity issue that we have to watch for? I don't see any markings on mine other that the numbers you stated. Thanks, Joe
There's no need to replace all the TVS diodes if one is shorted, you're just risking PCB damage for no gain.
No polarity on the TVS parts, they're bi-polar.
First step is to check continuity across the outputs with the TIU totally disconnected from everything. If you have a short, or only a couple of ohms, replace that TVS. This is the TVS I use, though if you're running at more than 22 volts input to the TIU, I'd probably bump it up to the next higher voltage level.