Hello everyone, I am having issues doing installation resistance phase to phase on a ABB tmax xth5 breaker. It is ready a dead short between the phases we took out the the rating plug and it is still reading a short. Has anyone come into this issue? Testing at 1 kv
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There is also nothing connected to the breaker as well.
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I had this problem as well. There is some information in one of the ABB XT5 manuals that explains how to isolate the PTs. Look up manual 1SDH002267A1001. It’s kind of vague. I found a manual a few months ago that described exactly what to take apart but I can’t find it now. With ABB you will have to look at a lot of their manuals to find little parts of the information you need. What kind of trip unit is it?
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Would likely need full part number to tell you exactly what is holding you out but the XT series has a bunch of options for “internal” accessories. The manual will tell you all the accessories that SHOULD be removed to meg. They are kind of a pain to get to so hopefully you only have a few to deal with.
We had one customer that didn’t want us breaking the case open to meg phase to phase.
They wanted us to leave the field blank in the test form and note something like “Unable to perform phase to phase insulation resistance due to breaker internal accessory options installed”
If I remember right, we had YU options for an undervoltage release that was holding us out. There may be a QR code on the breaker that you can scan for info.
Here is a video of the internal options.
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I appreciate all the information guys I will be looking into that and the trip unit is a EKIP touch LSI
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It’s the trip unit. Not worth taking the breaker apart to remove internal pieces for a phase to phase megger test on a UL certified component. Open the breaker and megger phase to phase, then close. I bet it will build voltage just fine with the breaker open, as the trip unit is on the load side. Good luck!
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In all of these newer style breakers, the trip units act as power quality meters. I’m pretty sure there are voltage taps for each phase.
I just responded to an emergency call where some EATON breakers got wet. They are the insulated case breakers equipped with the PXR trip units. After tearing the breaker apart, I found 3 bundles of multicolored wires attached to each phase. Once I separated the connectors, I was able to perform insulation resistance. Of course I was investigating because everything was wet and insulation resistance was 12 megohm phase to phase and phase to ground.
With the trip units and breakers becoming more advanced with technology, it is becoming more difficult to perform basic tests.
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ifr is right. Here is the supporting documentation. ABB does actually do a pretty decent job with those QR code on the front of the breakers. Takes you to a breakdown of what it has and the relevant manuals. You will have to click around a bit.
Here, this is were you will end up ABB Library - 1SDH002267A1001
scan this QR code. if you are using you phone it should take you right in. on a laptop you may need to create an ABB login.
takes you here.
scroll down and you will see all the manuals for the items on the breaker. click manual for the breaker itself
in the manual. go all the way to the bottom “Testing” section. Read note about withstand testing and the doc it points you to. (link above, snip below)
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So I did some research last weekend and ended up having to take the trip unit off of the breaker to meg it phase to phase. The front cover has to come off and there are 3 torx screws that have to be loosened, and then there are 4 more allens on the bottom of the breaker, by the lugs, that have to come out, that hold the trip unit to the breaker. Once you get the trip unit off you can meg the breaker. No way to do it with the breaker installed.
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