We are having an output limit failure on our power supply unit even when nothing else is plugged in. Our other system kept doing same thing when we did test on components that plug into it we found that our tether had weak insulation and after locating the spot on tether we fixed it and no more problems. But now with this system we have a good tether and we are having output lim fail. We tried unpluging components one by one and it even does it when nothing is plugged in. I’d like to get some ideas on what it could be before I have to get inside the PSU to atleast know where to begin. has anyone experienced this before?
Are you saying the LIM is indicating a fault, even if you have the umbilical unplugged from the surface unit?
When you had the fault on the umbilical did you by any chance use a megger/insulation tester on the power lines while fault finding? And if so, was the LIM still connected to the umbilcal?
If you did, you could have blown the LIM, cos they dont like being zapped with a megger.
When we were testing the umbilical it was on a dif PSU but yes we had it unplugged. now we are on a completely diff. PSU after fixing first system. when the second system output lim fail light comes on it also will display on th A-Isometer / Insulation Monitoring device the little light above the #40 as well as Alarm 2+ will also light up.
But yes we unplugged umbilical from surface unit and it still indicates a fault. Do you know what that could mean
have a look at this thread. Reccomendation is that you offload the manual for hte lim unit and have a good double-check of the dip switch settings on your machine. I think the web-link to the 2-page pdf is on that thread.
Also remegger your umbilical. Do you have anything less than GigOhm?
The tether is ok. The lim fault is happening even when nothing is plugged into power supply unit. I assume its something within the PSU but I’m tryin to get some ideas before getting into it.