Electrical Safety for newbies - Page 1
Forum section: electronics / general

author: SteveLuck
author_rank: Newbie
timestamp: December 29, 2011, 05:48:05 am
content: Any chance of a blog or two on Electrical Safety for newbies - I've all ready been told measuring amps on an ATX power supply without a load was a bit dodgy, there must be quite a few more like that some obvious - not shorting Nicad batteries etc and some nowhere near as obvious but still a little hazardous.ThanksSteve

author: IanB
author_rank: Super Contributor
timestamp: December 29, 2011, 08:14:15 am
content: Quote from: SteveLuck on December 29, 2011, 05:48:05 amThis is not even a bid dodgy, it simply makes no sense. It's a bit like "measuring the weight of some apples with a ruler".QuoteShorting things is normally and generally bad. The number of times where it is sensible to make a deliberate short circuit can be counted on one hand.IMHO, you can't really be safe without understanding what you are working with. Otherwise you will just be following rules by rote. Richard Feynman was once asked to do a safety course for workers in the atomic bomb lab during the war, but he was not allowed to teach them about the processes they were working with because the information was classified. He responded he couldn't do that; he could not teach the workers how to work safely unless they understood what they were working with.The same with electricity. Learn as much as possible about how electricity works and what you do with it and what it can do to people or equipment, and then you can understand how to be safe.

author: SteveLuck
author_rank: Newbie
timestamp: December 29, 2011, 09:52:12 am
content: “Any man can make mistakes, but only an idiot persists in his error”Unfortunately with electricity you don't always get the chance to repeat your mistakes - better to learn from the mistakes of others!So a few examples for those of us less enlightened wouldn't go amiss!I know what amps volts and resistance are and the relationship between them however - I hadn't considered putting a meter across a power supply output as being the same as shorting it merely checking to see what it would put out before i fried anything connected to it!Newbie mistake

author: Psi
author_rank: Super Contributor
timestamp: December 29, 2011, 12:48:42 pm
content: Quote from: SteveLuck on December 29, 2011, 05:48:05 amheh, its worse than "a bit dodgy".If the powersupply fails to detect the short and stays online it will quite happily pump 30+ amps into the wires and light them up like a Christmas tree.Also turning the insulation on the wire into a room full of horrible burnt PVC smoke.Not to mention serious burns if the wire is touching you at the time.

author: Unknown
author_rank: Unknown
timestamp: December 29, 2011, 04:32:57 pm
content: Which is why all good DMMs have fused current inputs.

author: SteveLuck
author_rank: Newbie
timestamp: December 29, 2011, 08:26:03 pm
content: OK so what else is there that's not blindingly obvious to a Novice -Examples from other industries:If you train as a welder you're taught you don't put grease on oxygen fittings because the grease can combust in the presence of oxygen. Unless you're trained a bit of grease might look like a good idea on a stiff fitting!If you're a machinist you're taught not to wear jewelry because the cutting oils next to the skin cause dermatitis.I'd never heard of solder splash until i watched Dave's video on soldering I'm probably lucky I wear glasses all the time.Whats with the expensive rubber mats on Dave's bench I see they are conductive - are they earthed as well?It's got to be worth a video even if it bores the pants of those that already know what they're doing.