ProSoundWeb Community

Sound Reinforcement - Forums for Live Sound Professionals - Your Displayed Name Must Be Your Real Full Name To Post In The Live Sound Forums => AC Power and Grounding => Topic started by: Ned Ward on October 11, 2019, 12:30:46 pm

Title: Current measurement tool for Lounge Level?
Post by: Ned Ward on October 11, 2019, 12:30:46 pm

OK, so while you can scour the owners manuals and webs to estimate current draw, what tools can be used to check how much current is being drawn on 15 or 20 amp circuits? We recently played at a church fundraiser where the circuits tripped and our keyboard kept resetting due to voltage dips.


Not looking for Fluke tester, but something that plugs into power to help folks understand how much power is being drawn from stage, PA, lights, etc.


This is less for full time show people, and more for those lower-rung fundraisers or festivals so that we know how many amps are being drawn...


thanks!

Title: Re: Current measurement tool for Lounge Level?
Post by: Chris Hindle on October 11, 2019, 12:40:24 pm
Look for the Coffee Pot that was on his circuit......

Seriously though, I have a clamp on ammeter, and I made a handful of 1' long AC "plugs and sockets" that give me access to the inner conductors.
You'd be surprised how little current most audio stuff draws.
Except PM3K's...........
Chris.
Title: Re: Current measurement tool for Lounge Level?
Post by: Andrew Broughton on October 11, 2019, 01:00:00 pm
http://www.p3international.com/products/kaw-chart2.pdf
Title: Re: Current measurement tool for Lounge Level?
Post by: Rick Earl on October 11, 2019, 02:25:15 pm
OK, so while you can scour the owners manuals and webs to estimate current draw, what tools can be used to check how much current is being drawn on 15 or 20 amp circuits? We recently played at a church fundraiser where the circuits tripped and our keyboard kept resetting due to voltage dips.


Not looking for Fluke tester, but something that plugs into power to help folks understand how much power is being drawn from stage, PA, lights, etc.

I keep one of these with me and use my regular clamp on meter: https://www.kleintools.com/catalog/test-measurement-accessories/line-splitter-10x (https://www.kleintools.com/catalog/test-measurement-accessories/line-splitter-10x)


This is less for full time show people, and more for those lower-rung fundraisers or festivals so that we know how many amps are being drawn...


thanks!
Title: Re: Current measurement tool for Lounge Level?
Post by: Jeff Bankston on October 11, 2019, 02:30:38 pm
Look for the Coffee Pot that was on his circuit......

Seriously though, I have a clamp on ammeter, and I made a handful of 1' long AC "plugs and sockets" that give me access to the inner conductors.

Thats the same things I use.

Title: Re: Current measurement tool for Lounge Level?
Post by: Frank Koenig on October 11, 2019, 02:54:56 pm
OK, so while you can scour the owners manuals and webs to estimate current draw, what tools can be used to check how much current is being drawn on 15 or 20 amp circuits? We recently played at a church fundraiser where the circuits tripped and our keyboard kept resetting due to voltage dips.

Kill-a-Watt. I've had one for years. It's awesome.
http://www.p3international.com/products/p4400.html (http://www.p3international.com/products/p4400.html)

--Frank
Title: Re: Current measurement tool for Lounge Level?
Post by: Tim McCulloch on October 11, 2019, 03:07:40 pm
If the problem was tripping breakers the question is "what else was on that circuit?"

No Kill-a-What? is going to tell you that and without opening the service panel you won't get your ammeter clamp around the wire to see what other loading may be on that circuit.

You can know everything about YOUR gear's current demands but unless you supply the distro and get a power tap, you don't know who or what is sharing your circuits.  This is why I went to tapping power long before it became fashionable... ;)
Title: Re: Current measurement tool for Lounge Level?
Post by: Jeff Bankston on October 11, 2019, 03:37:39 pm
I worked as a commercial electrician and wired up new businesses etc. Some of the plans had several receptacles near each other and another(s) some distance away on the same circuit. I have done trouble shooting before and it can take a while finding all the recepts that are on the same breaker. Once the owner/tenant moves in they might have all kinds of stuff running off a circuit that has recepts spread out. Best thing to do is pull the panel cover and clamp a meter on the circuit thats tripping to see if there is a current draw. Could be computer(s), small refrige, etc. I wired up a couple of night clubs and the stages had there own separate circuits but that doesnt mean another electrician hasnt come along and tied a coffee pot recept to a stage j-box.
Title: Re: Current measurement tool for Lounge Level?
Post by: Frank Koenig on October 11, 2019, 03:39:20 pm
No Kill-a-What? is going to tell you that and without opening the service panel you won't get your ammeter clamp around the wire to see what other loading may be on that circuit.

Fair enough. If there's a problem with the building wiring the standard PSW answer is hire an electrician. If you're going to play electrician yourself, a pleasure I would not deny anyone, get the professional tools which would include a good Volt-Ohm-milliammeter, a clamp-on AC current probe, and possibly some sort of power-quality logger.

If you're trying to figure out what YOUR stuff draws, and the loads are less than 15 A, the Kill-a-Watt is an excellent tool. It shows, voltage, current, power, apparent power, power factor, and can integrate power to give total energy. Not bad for ~$30. And no batteries!

--Frank
Title: Re: Current measurement tool for Lounge Level?
Post by: Ed Hall on October 11, 2019, 04:05:42 pm
Look for the Coffee Pot that was on his circuit......

Seriously though, I have a clamp on ammeter, and I made a handful of 1' long AC "plugs and sockets" that give me access to the inner conductors.
You'd be surprised how little current most audio stuff draws.
Except PM3K's...........
Chris.

I have similar. Made it from some spare parts so it cost me nothing except the 5 minutes to assemble it. I’ve tested most of the gear running at FTB so I already have an idea of what it draws.

It lives in my tool kit along with the meter. I meter EVERYTHING before I plug anything in.

I don’t use a PM3K.  ;)
Title: Re: Current measurement tool for Lounge Level?
Post by: Ned Ward on October 11, 2019, 07:52:35 pm
If the problem was tripping breakers the question is "what else was on that circuit?"

No Kill-a-What? is going to tell you that and without opening the service panel you won't get your ammeter clamp around the wire to see what other loading may be on that circuit.

You can know everything about YOUR gear's current demands but unless you supply the distro and get a power tap, you don't know who or what is sharing your circuits.  This is why I went to tapping power long before it became fashionable... ;)


Tim - this is the best answer for most. Finding out what else is plugged into it is half the battle (actually, Knowing is Half the Battle™ but I digress); the remainder is something simple for the volunteers to understand how much power things draw (showmobile lights, PA, band gear) and to block off or plug in dummy cables to prevent the coffee maker from plugging in.



Title: Re: Current measurement tool for Lounge Level?
Post by: Miguel Dahl on October 20, 2019, 10:29:11 pm
Never heard of or thought about it myself. But dummies sounds like a great idea for the jobs where one can risk a tripped breaker caused by someone else that you. Great tip. "run in at half power max" just doesn't work.