Yikes, why'd this symmetra blow up? (pic attached)

[Anonymous user]

I need help determining why this SY16K backplane blew up. I've come to realize that I'm going to have to replace this very expensive unit, but I don't want to buy a replacement chassis (probably off ebay?) until I know what caused it. If it is a bad symim, syrim, sypm, or sybatt module, I don't want to fry another chassis.

This photo is from the top of the back of the unit, I've removed the card slots to expose the rim/mim backplane. The AC_1 and the feed next to it (can't read the label, it's all burned) have arc'd, and it looks like something in the middle of the mim connector has gone poof.

This unit was recently installed by an electrician with a manual on hand. I spun it up myself, everything looked good. I left it, and when I came back the next day the breaker on the building panel was blown and when I flipped it back on, the unit would not power up. With the manual bypass enabled I have verified the input and output voltages with a meter, so I'm 95% certain the electrician did everything properly.

I hope someone can help pin this down! Thanks!


-edit/add-
I pulled apart the mim and there is no obvious sign of damage inside.

Message was edited by: kattare

[Anonymous user]

Thanks for the info.

I pulled the MIM and tested it in another chassis. It is definitely dead. Pulled the RIM and tested it as well, it too is dead. The other power modules seem ok.

Then I disassembled the MIM, no signs anywhere of burning or popping. Disassembled the RIM next and found the cover blown off of one of the IC's (one of the three prong ones with heatsinks) with various chunks of it loose inside there.

It seems like a pretty bad design flaw if a blown IC in a RIM can take down the MIM and destroy the backplane?

Or if the RIM failure is a side effect of a failure somewhere else, still seems a pretty bad design if failures in any of the swappable modules can take out the entire "redundant" system and fry the pieces of it that are supposed to be permanent... (the backplane) Crazy.

So I've looked at the LX's. They definitely seem to be where I'd like to go. Question now is... are the design flaws worked out? What is the chassis failure rate on the LX vs the previous units?

Thanks!

[Anonymous user · Accepted solution]

Sounds great, thanks a bunch for the info!