Recommendation for amperage on extension cords.

[ahoustondj]

OK I am still encountering a lot of firsts since leaving the Club scene. Its been 8 years now so I can't recall. I'll be doing a wedding in an outside venue about 4 acres behind a house. Client will be supplying me with power in a 40' x 80' tent. I'll more than likely be running 2 power conditioners, 4 power amps, laptop, HD, mixer, dual cd players, EQ, Compressor/Expander, Reverb, 3 way electronic crossover and maybe some misc stuff like a fan etc. What ampage should I request/ensure that I have for safe operation?
Gosh! I long for the days where you just plug the sucker in and hope for the best.

 

[Fred Wright]

What you require and request may be moot, my friend. The available service is what it is. I'd strongly suggest that you make an appointment with the client, drive to the event location and see for yourself what they'll be doing.

You're not gonna run four power amps on a 20 amp branch circuit 4 acres away from the supply, sorry. If you're gonna be set up that far from the house, rent a generator and power your rig with it. Or have the client provide a genny for your use.

This would be my recommendation.

 

[ahoustondj]

What you require and request may be moot, my friend. The available service is what it is. I'd strongly suggest that you make an appointment with the client, drive to the event location and see for yourself what they'll be doing.

You're not gonna run four power amps on a 20 amp branch circuit 4 acres away from the supply, sorry. If you're gonna be set up that far from the house, rent a generator and power your rig with it. Or have the client provide a genny for your use.

This would be my recommendation.

Let me clarify. Sorry I was not clear. The field is 4 acres but the setup is close to the house (Guess the size of the field is irrelevant). I will be going down to see the place and also the setup before the event. I do not like using generators especially if the client is supplying. I have used them in the past in Boston running as much as 6 amps plus all the other electronics and 8 huge bass bins on an outdoor stage with no problem except for the noise from the generator itself. This was back in the 70's. It is my understanding that the generators are now more quiet and stable. I still don't trust them.

 

[Fred Wright]

Ah, OK.

In this case, I'd suggest setting up as close to the house as you can. If you're gonna be set up in a tent, this may be a stretch. Please ensure that you'll have at least two dedicated 20 amp outlets available to you.

I'd suggest splitting the power amp load between the circuits with the frontend equipment shared with the highs/mid amps. The lows amps should be fed with their own AC circuit. Just a reminder ~ you don't need to run power amps through conditioners.

Get a measurement of the distance you'll be running your power. Take into account the extra distance with twists and turns... going around the deck, for example. It's never as the crow flies. Get no smaller than 12 gauge AC cords for your runs.

Do not depend upon the client to provide these... they always say they will but they never do. Leave it to them and you may end up at the end of a pipsqueak AC cord that's better suited for running a hedge trimmer. And they've got the tent festoon lighting on the same damn circuit. We have seen this.

Find the outlets you'll need, make a note of where they are and tell the client that you (and you alone) will be using them for the duration of the engagement. They are not to be used for anything else during the show, that's final. No coffee makers, no freezers, no fridge, no festoon lighting, no nothing. And do not let anyone wheedle you into sharing with catering etc. They can find their own power.

Then obtain 12 gauge extension power cords that will be long enough to get to the tent area. These can be got at Lowes or Home Depot. Ensure that they are 12 gauge before you buy them. The wire gauge is printed on the cable jacket.

I apologize for the long post but I wanted to help you avoid some of the pitfalls we've dealt with at outdoor shows over the years. Bring everything you will need to the show. Please don't take someone else's word that what you need will be there. It rarely is.

The reason I say all this ~ if you are at the end of a pipsqueak cord your bass thump will dim the lighting and quite possibly kill the power altogether. You don't need the headaches. Ensure that you'll have a couple of 20 amp branch circuits dedicated for your use.

Hope it helps.

 

[ahoustondj]

Ah, OK.

In this case, I'd suggest setting up as close to the house as you can. If you're gonna be set up in a tent, this may be a stretch. Please ensure that you'll have at least two dedicated 20 amp outlets available to you.

I'd suggest splitting the power amp load between the circuits with the frontend equipment shared with the highs/mid amps. The lows amps should be fed with their own AC circuit. Just a reminder ~ you don't need to run power amps through conditioners.

Get a measurement of the distance you'll be running your power. Take into account the extra distance with twists and turns... going around the deck, for example. It's never as the crow flies. Get no smaller than 12 gauge AC cords for your runs.

Do not depend upon the client to provide these... they always say they will but they never do. Leave it to them and you may end up at the end of a pipsqueak AC cord that's better suited for running a hedge trimmer. And they've got the tent festoon lighting on the same damn circuit. We have seen this.

Find the outlets you'll need, make a note of where they are and tell the client that you (and you alone) will be using them for the duration of the engagement. They are not to be used for anything else during the show, that's final. No coffee makers, no freezers, no fridge, no festoon lighting, no nothing. And do not let anyone wheedle you into sharing with catering etc. They can find their own power.

Then obtain 12 gauge extension power cords that will be long enough to get to the tent area. These can be got at Lowes or Home Depot. Ensure that they are 12 gauge before you buy them. The wire gauge is printed on the cable jacket.

I apologize for the long post but I wanted to help you avoid some of the pitfalls we've dealt with at outdoor shows over the years. Bring everything you will need to the show. Please don't take someone else's word that what you need will be there. It rarely is.

The reason I say all this ~ if you are at the end of a pipsqueak cord your bass thump will dim the lighting and quite possibly kill the power altogether. You don't need the headaches. Ensure that you'll have a couple of 20 amp branch circuits dedicated for your use.

Hope it helps.

Thanks for all the helpful information. Just to cover myself though (I met with the groom yesterday), I will be including these requirements in my written agreement and when I go to do the rehearsal (I won't be using the big system for the rehearsal), I'll inspect everything to make sure its ready for me the next day.
I was given the legal advise that it is better to have the Client supply ALL the AC/Power and requirements to you at the place/booth where you have your equipment. The reason for this is because if something goes wrong and circuits catch on fire, you will not be held responsible, they will. As a matter of fact, if your gear gets damaged they will have to pay you and not the reverse. So that will be included in the agreement. Yes yes yes, I will still get my own 12 gauge extension cord, just in case! Once again thanks!

 

[DougF]

One other thing to watch out for: BE SURE the outlets ARE all on SEPARATE circuits and not shared with something inside the house!

 

[Balanced Line]

Talk about fun...

It is so much fun to listen to bass notes hit and watch lights dim to the point where it drops to 100V.

This is one of those instances were the old class AB amps with the big filter caps are a better choice. They do better on soft supplies than the latest class D amps that generally require "stiff*" supply. Lights still dim though...

*stiff - meaning the supply voltage doesn't sag

 

[DJ SVO]

I've had good luck when running 50 ft. 10 gauge extensions delivering the proper voltage at a friends house when I'm not able to tap in with my pówer distro.

 

[Balanced Line]

No Luck Necessary

Let's look at the numbers.

A fifty foot cord needs 100 feet of wire. Out on the black hot wire and back on the white neutral wire. One hundred feet of #10 wire is .1 ohm. One hundred feet of #12 is .159 ohms.

What we want to know is what's the voltage drop? E = I*R. Worst case the current will be 20 amps. 20 * .1 = 2 volts drop for the #10 cord. For the #12 cord, the computation is 20 * .159 = 3.18 volts drop. These are the figures while drawing 20 amps. If you draw half this much (10A) the voltage drop would be half that much or 1 and 1.59 volts respectively.

If you carry a #10 versus a #12 cord you "saved" or didn't loose 1.18 volts in I squared R (copper) loses @ 20 amps of current. As you can see, for a cord 50' long the larger wire is hardly worth it. It only becomes critical when the wire is 150 or 200 feet long or longer AND you are drawing large currents. Don't forget the house wire is only #12 and in an old structure may be #14 and limited to 15 amps at the breaker or fuse.

So SVO if you have to go 200 or more feet some time in the future, you have a good start. Kind of heavy though.