so i learned a lesson today!

[pro]

What would you have done if you did read the voltage at 208 prior ?

[Remoteness]

You experienced an interesting encounter that I bet you will never address the same way again.

I’ve been there and understand everything you encountered.

IMO, just because the person you work for is not forward thinking does mean you have to follow their path.

Upfront I want to say, "I’m sorry if I’m being too heavy, but you ARE dealing with live power that can do much more damage than blowing up sound equipment".

If you don't think I'm being heavy, please read on!

One thing you have to remember is people make mistakes.
Even professionals can be off their game.
I understand the concept of trusting your fellow teammates, but you must verify especially if you never dealt with that person.

I don’t understand why you folks never metered the feed from the generator?
Even if you didn't have a meter, you should have asked the power company to meter your feed.
With that said, I cannot believe the power company didn't meter the distro themselves.
This is so un-cool to say the least.
It's the first thing you should do before you power up your rig.

I designed ASL’s AC isolation transformers have meters and pilot lights before the main breakers so you can see if you’re energized and you have the correct voltage before you flip the breakers. We always meter, so I though why not install a permanent meter and such. Elroy has meters and pilot lights plus banana plug test points to make sure the meters are on point and if they fail we still have a way to easily check the voltage coming to our truck power panel.

Click on the two links to view a couple of pictures of our portable ISO XFMR.
The analog meter and pilot light is wired after the input Cam-Loks and before the main breaker.
http://www.gearslutz.com/board/attac...lexfmr2299.jpg
http://www.gearslutz.com/board/attac...lexfmr2309.jpg

IMO, whether or not you’re using your own equipment you must always meter the feed before you turn power on. It’s simply the only way to deal with power, especially when you’re not familiar with the company supplying it.

Metering the feed (before energizing) should have been the standard method of operation for the sound company you work for. I mean whether or not the guy from the power company is insisting it’s not their fault you should have metered the feed.
A sound company without a multi-meter in their tool box is not a real sound company.

I’m trying to find the logic in all this. I cannot believe the guy you work for asked you to try another amp on another circuit before testing the voltage. This is simply insane behavior to say the least.

Next time if you don’t have a meter try a light bulb before you consider using a power amp and a test set.

Next time consider running to Radio Shack or a hardware store and buy a meter or a light bulb -- it's much cheaper than two power amps.

In any even I still dig you because you walked away learning something very iimportant.

[Remoteness]

Originally Posted by pro

What would you have done if you did read the voltage at 208 prior ?

• I would have not blown up two power amps

• I would have call the power company rep and said, I have 208v on my 120v line

• I would have checked to see if the hot and neutral was reversed

Besides checking for the correct voltage you should also check for ground potential.
Checking the voltage between ground and neutral would have found the problem on the spot.

I hope this hepled.

[Jim vanBergen]

This is the kind of lesson I learned watching a mentor (who had a VERY bad day) in the late 80's, and I think it's SO GREAT to know that the next generation of people can learn this the easy way, not the hard way!

I carry one of the cheap-o Rat Shack analog VU power meters as well as the home depot three-led lights that confirms when your hot, neutral and ground are correctly wired. Those are on a three-way AC plug, it's the first thing plugged in at a new venue or new outlet! I can't control when my gear has a bad day (had a Hafler amp blow and took my Dynaudio monitors with it!) but I can control what I plug in, and if the house power is safe!

[nathanvacha]

yeah. i'm always used to using the same generator/distro usually when i work for this company, but it was different this time. there were already other people up and running, but must have been on a different feed... there were i think three different distro's going. but yeah, felt like a stupid mistake, but i'd never encountered that before. i'll check out those links you posted too, steve. thanks.

[Remoteness]

The items JvB mentioned are excellent (sound engineer) tool box stuffers.
Pretty standard items for our kind of work.

Maybe we should start a thread or add it to my (sticky) beginners thread about items for the ultimate sound & audio survival kit...

Maybe even take a few pictures and stuff.


If any one wants to start a thread I'll merge it into that sticky thread.

[nathanvacha]

that's a really good idea too, to start a sticky like that. i usually carry the voltmeter along when i'm doing a job with any real setup, and i've been meaning to pick up one of those light up outlet testers too. i guess that's motivation to make a trip to the hardware store.

[Testing123]

If you get stuck without a meter you could find an incandescent lamp (60W, 100W, watt-ever) to plug in. It will either:

a) not light
b) light
c) pop like a flashbulb

-Keith

[Remoteness]

Originally Posted by Testing123

If you get stuck without a meter you could find an incandescent lamp (60W, 100W, watt-ever) to plug in. It will either:

a) not light
b) light
c) pop like a flashbulb

-Keith

Great suggestion Keith, especially about popping like a flash bulb!

I did mention this in post #3...

I stated:

Next time if you don’t have a meter try a light bulb before you consider using a power amp and a test set.

Next time consider running to Radio Shack or a hardware store and buy a meter or a light bulb -- it's much cheaper than two power amps.

[Testing123]

Originally Posted by Remoteness

I did mention this in post #3...

Sorry - read right past that...

[Remoteness]

Originally Posted by Testing123

Sorry - read right past that...

No worries, I like the way you broke it down.

Well said and thanks for posting it!

[Nick_1234]

Steve.

I would be real interested in seeing how that "tool kit" thread evolves. Could you provide me with the link? Or should the search cover it?

Respect.

[bove]

I always use one of those Home Depot "3 LED" outlet testers before I plug in, and last week I found my first mis-wired outlet... not as exciting as exploding amplifiers, but I did avoid using a non-grounded outlet!

[peeder]

Don't most power conditioners have voltage readouts? Active before you switch on the power conditioner?

I use a three-LED thing too. Amazing how often incompetent electric is out there.