Rigged up a temp panel for a job in downtown Denver and it almost got me fired

I was working a commercial fit-out on the 14th floor last month and my main panel feed had a delay. I threw together a temporary with some spare breakers and a junction box to keep the lights on. The inspector showed up and told me I bypassed the fire alarm shunt trip, which I totally forgot about. Has anyone else had a close call with a temp setup that made you double check everything?

3 comments

3 Comments

mitchell.wade2mo ago

That shunt trip thing is a pretty common miss though. Technically you only need it if the fire alarm system is actually tied into the elevator lobbies or mechanical equipment on that floor. A lot of inspectors will call it out anyway just to be safe. You could argue it wasn't a bypass if the fire alarm wasn't even active in that zone yet. Its one of those things where the code says one thing but the practical application is different depending on the building.

abbycraig2mo ago

Yeah and half the time the fire alarm guy doesn't even know when the shunt trip is supposed to work either.

hall.quinn21d ago

Doesn't the shunt trip actually kick in before the fire alarm panel even sends the full signal though? Usually the secondary power interruption triggers it, not the main alarm condition. So the sequence is already happening before most people pull out their meters.