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You would expect a qualified electrician to wire a building to spec, right? Trust... but verify

What could be wrong when two UPSes commit seppuku?

Who, Me? Welcome to an electrifying edition of The Register's regular Who, Me? feature in which a reader rues the day he decided to trust the electrician.

"Harry" (no, not his name) was toiling away in his first IT job back in the late 1990s. "I was working on a Y2K remediation project," he told us, "for a large law firm."

The US-based law company was dealing with Y2K in the time-honoured fashion: new servers and updated PCs for all!

Each branch office was to receive new kit, built by Harry's betters at the mothership. Our hero was tasked with setting up the gear. Once he was done, his more senior colleagues would arrive to deal with the transition from old to new server.

"After setting up several branches," he boasted, "I got into a routine and was quite proficient."

While there is a saying about pride coming before a fall, we can't think of something for what happened next.

"About halfway through the project," he told us, "we got to the branch that happened to be 10 minutes from my apartment. I was thrilled – instead of driving an hour or more to a distant branch, I would have a nice, easy time for this one time on the schedule."

Harry followed the familiar process. A pair of HP servers – one for NetWare and one for Windows NT – were set up. There was a monitor, keyboard, mouse, and KVM switch, a well-specified UPS to keep the juice flowing smoothly, and, bizarrely, a wireframe baker's rack on which to assemble everything. "For some reason," he shrugged, "my company did not do server racks."

He hit the power button on the UPS and... nothing. Bereft of the familiar sound of computer hardware whirring into life, Harry double-checked everything, but the UPS remained dead. Sticking its power lead into another wall outlet to test wasn't an option. This device needed an L5-30 twist-lock plug and required more amperage.

"Diagnosing as best as I could, I guessed that the UPS had a casualty in transport. The thing was built like a tank, but it did have some circuitry inside, so I assumed that something broke between the shop and the branch."


Two clichés, one headline: 'No good deed goes unpunished' and 'It's always DNS'


No problem. He called up the workshop, who agreed with his diagnosis ("speculation, really") and had another unit ferried over by a co-worker. Harry exchanged the tank-like UPS units and was back in business... or so he thought.

"I plugged in the new UPS and hit the power button...

"This time, sparks and flames shot three feet out the back of the UPS! In near-panic (I've always been nervous about electrical shocks, plus it would not do to burn down the client's building), I unplugged the UPS as fast as I could."

Unnerved and, we suspect, possibly in need of a fresh pair of trousers, Harry called the project's tech lead to unload the bad news. The boss took a pragmatic approach and told him to simply plug the servers into the regular wall sockets. The UPS could wait until another day.

Later investigation revealed that the electrician responsible for the building had wired the outlet for 220 volts rather than 110 volts. One UPS had reacted to the difference by quietly dying. The other had taken a more explosive path.

"Several days later, I bumped into the electrician, and he claimed that he had never thought to check the specs, because in his whole career he had never installed an outlet for a twist-lock plug that was anything other than 220 volts.

"I found out later that an L5-30 plug specifically indicates a 110-volt, 30-amperage device, so this electrician might have needed a bit of remedial training."

Indeed. The difference between L5 and L6 would be good for starters. We particularly enjoyed this Reddit thread on the topic, in which one contributor stated bluntly: "And don't hire whoever installed your L5-30R running 220 V, because whoever did that is an idiot."


As for Harry, he bought himself a multimeter the very next day to check future outlets just in case he ran into the work of another electrician who "had never thought to check the specs."

"I never had an issue after that first time," he said, "but I decided to adopt a phrase from the previous decade – trust but verify!"

We prefer the old pilot's adage: "The guy in the other seat is trying to kill you," although when we heard it, the flier telling the tale substituted "guy" with a word not suitable for a family publication like El Reg.

Ever found yourself at the sharp end of another's failure to follow process? Or made your own fireworks with the assistance of the wrong power supply? Share your brush with the reaper in an email to Who, Me? ®

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