ProSoundWeb Community

Please login or register.

Login with username, password and session length
Advanced search  

Pages: 1 2 [All]   Go Down

Author Topic: Electrical safety question  (Read 4637 times)

Rafi Singer

  • Newbie
  • *
  • Offline Offline
  • Posts: 44
    • Singer Production Company
Electrical safety question
« on: May 19, 2011, 01:58:22 am »

This might be an obvious answer, but I figured I'd ask it anyhow.

I was taking a look at the QSC PL4.0's and saw that they use a twist-lock 30A connector. This would prove to be somewhat impractical, as some of the locations I would want to use it would not have that type of receptacle available. Assuming I could have a separate circuit for the subs, is there anything inherently dangerous/bad about using an adapter to plug it into a standard Edison 20A outlet?
Logged

John Neil

  • SR Forums
  • Newbie
  • *
  • Offline Offline
  • Posts: 44
Re: Electrical safety question
« Reply #1 on: May 19, 2011, 02:40:17 am »

I know "someone" who tripped a 20a with a 4.0.  It wasn't under "normal" conditions. 

Logged

Charlie Zureki

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 1244
  • South Eastern Michigan (near Windsor)
Re: Electrical safety question
« Reply #2 on: May 19, 2011, 07:10:02 am »

This might be an obvious answer, but I figured I'd ask it anyhow.

I was taking a look at the QSC PL4.0's and saw that they use a twist-lock 30A connector. This would prove to be somewhat impractical, as some of the locations I would want to use it would not have that type of receptacle available. Assuming I could have a separate circuit for the subs, is there anything inherently dangerous/bad about using an adapter to plug it into a standard Edison 20A outlet?

  The  QSC specs state that this Amp requires a 30 amp circuit,  Why would you think a 20 amp circuit is appropriate only to you ?

   Hammer
Logged
Do it the right way....don't be a Dino!

Tim McCulloch

  • SR Forums
  • Hero Member
  • *
  • Offline Offline
  • Posts: 20854
  • Wichita, Kansas USA
Re: Electrical safety question
« Reply #3 on: May 19, 2011, 07:33:13 am »

This might be an obvious answer, but I figured I'd ask it anyhow.

I was taking a look at the QSC PL4.0's and saw that they use a twist-lock 30A connector. This would prove to be somewhat impractical, as some of the locations I would want to use it would not have that type of receptacle available. Assuming I could have a separate circuit for the subs, is there anything inherently dangerous/bad about using an adapter to plug it into a standard Edison 20A outlet?

Build an adapter cable.. L5-30 (I think) female to either the 20 or 15 amp Edison male, and accept that you might trip breakers when running hard.  This would be 'safe' in that you are not using wiring devices (the plugs/receptacles) on a service that is protected by a breaker or fuse rated for more than the lowest rated device, presuming the circuit the Edison it on is protected for it's 15/20 amp rating.

Unsafe would be building this adapter or wiring a 15/20 amp Edison to the amp cord and then plugging into a circuit with a 30 amp breaker.

That's the bare bones physics of it; Code may not like this depending on where you are.
Logged
"Practicing an art, no matter how well or badly, is a way to make your soul grow, for heaven's sake. Sing in the shower. Dance to the radio. Tell stories. Write a poem to a friend, even a lousy poem. Do it as well as you possible can. You will get an enormous reward. You will have created something."  - Kurt Vonnegut

Rafi Singer

  • Newbie
  • *
  • Offline Offline
  • Posts: 44
    • Singer Production Company
Re: Electrical safety question
« Reply #4 on: May 19, 2011, 09:49:07 am »

  The  QSC specs state that this Amp requires a 30 amp circuit,  Why would you think a 20 amp circuit is appropriate only to you ?

   Hammer

My thinking is along the lines of what Tim said above. You're dealing with a higher pull, rather than a higher push. The plugging a 20A device into a 30A socket is a no-brainer. However, I am not sure what the risks are of plugging a spec'ed 30A device into a 20A circuit, aside from potentially tripping a breaker. Ergo, I'm asking everyone else!
Logged

Chuck Simon

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 1139
  • Pittsburgh, Pa.
Re: Electrical safety question
« Reply #5 on: May 19, 2011, 10:14:20 am »

Follow Tim's advice.  I do it all the time(and I'll bet many others do also) with a PL 4 and have never blown a 20 amp circuit.  I do make sure it is the only amp on that circuit.
Logged

Franklin Benjamin

  • Jr. Member
  • **
  • Offline Offline
  • Posts: 82
Re: Electrical safety question
« Reply #6 on: May 19, 2011, 10:36:23 am »

This might be an obvious answer, but I figured I'd ask it anyhow.

I was taking a look at the QSC PL4.0's and saw that they use a twist-lock 30A connector. This would prove to be somewhat impractical, as some of the locations I would want to use it would not have that type of receptacle available. Assuming I could have a separate circuit for the subs, is there anything inherently dangerous/bad about using an adapter to plug it into a standard Edison 20A outlet?

I currently have a pair of 4.0's sharing a 30 amp circuit and I have yet to trip a circuit.  The amps are very efficient.  Take Tim's advice and build an adapter.  You should be fine.  disclaimer, I don't use them on subs.  I never did like the way they sounded on subs.
Logged

Rafi Singer

  • Newbie
  • *
  • Offline Offline
  • Posts: 44
    • Singer Production Company
Re: Electrical safety question
« Reply #7 on: May 19, 2011, 10:50:36 am »

I currently have a pair of 4.0's sharing a 30 amp circuit and I have yet to trip a circuit.  The amps are very efficient.  Take Tim's advice and build an adapter.  You should be fine.  disclaimer, I don't use them on subs.  I never did like the way they sounded on subs.

AHA!!! This was my initial thought of application. What in a similar range would recommend?

Logged

Tracy Garner

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 295
Re: Electrical safety question
« Reply #8 on: May 19, 2011, 11:08:02 am »

AHA!!! This was my initial thought of application. What in a similar range would recommend?

...same goes for Crown MA 2400 and higher except they used that camper-type 30Amp plug.
Logged

Chuck Simon

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 1139
  • Pittsburgh, Pa.
Re: Electrical safety question
« Reply #9 on: May 19, 2011, 11:11:07 am »

I think you should try them for subs and draw your own conclussion.  The PL 4.0 has worked for me  and many others with subs!
Logged

Franklin Benjamin

  • Jr. Member
  • **
  • Offline Offline
  • Posts: 82
Re: Electrical safety question
« Reply #10 on: May 19, 2011, 12:00:03 pm »

AHA!!! This was my initial thought of application. What in a similar range would recommend?
I would not be able to give you a good recomendation. I am using a 9.0 for subs.  In that price/ power range I am not sure.  My subs seem to carry a different character (how's that for a description) depending on the amp that drives them.  You might have a better result and opinions are very subjective.  Give it a try and see if you like it.  Because you are planning to run it for subs, be aware that you might trip the 20 amp circuit but it should be able to get pretty loud before that happens.
Logged

Brad Weber

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 2209
  • Marietta, GA
Re: Electrical safety question
« Reply #11 on: May 19, 2011, 01:54:16 pm »

My thinking is along the lines of what Tim said above. You're dealing with a higher pull, rather than a higher push. The plugging a 20A device into a 30A socket is a no-brainer. However, I am not sure what the risks are of plugging a spec'ed 30A device into a 20A circuit, aside from potentially tripping a breaker. Ergo, I'm asking everyone else!
That is assuming there is a properly rated breaker that is functioning correctly.  The problem would seem to be connecting a device that could try to draw more than the installed wiring and receptacle are rated to support, thus basically creating a situation that relies on what is supposed to be a safety device to provide current limiting during 'normal' use.  If you build an adapter you might include a 20A breaker in it so that what you are connecting can't pull more than 20A and you know that you have a working breaker on the line.
Logged

Geoff Doane

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 830
  • Halifax, NS
Re: Electrical safety question
« Reply #12 on: May 19, 2011, 04:40:09 pm »

  If you build an adapter you might include a 20A breaker in it so that what you are connecting can't pull more than 20A and you know that you have a working breaker on the line.

That would be sort of a "belt and suspenders" approach I guess.

Personally, I just wear a belt.  :)

You didn't mention what you are loading the amp with.  If it requires a 30A supply when running at 2 ohms, it will only need about half that when running only 4 ohms per channel, and a 20A circuit should be more than adequate.

GTD
Logged

John Neil

  • SR Forums
  • Newbie
  • *
  • Offline Offline
  • Posts: 44
Re: Electrical safety question
« Reply #13 on: May 19, 2011, 08:13:29 pm »

I know "someone" who tripped a 20a with a 4.0.  It wasn't under "normal" conditions.

That case was four subs per channel with heavily compressed hip-hop backing tracks.

On the other hand, I know of an outfit that has monitor racks with a pair of 4.0 and a pair of 1.0...four biamped mixes on a single 20a supply.  It's never an issue.

I've seen plenty of 4.0 with Edisons on them.  Even know of a few rogue 6.0 and pl380 set up the same.  Probably depends on the use.
« Last Edit: May 19, 2011, 08:20:14 pm by John Neil »
Logged

Josh Billings

  • Full Member
  • ***
  • Offline Offline
  • Posts: 227
Re: Electrical safety question
« Reply #14 on: May 19, 2011, 08:39:58 pm »

Lol I have a PL 6.0 on a 20 amp circuit (15 amp plug) and haven't tripped a breaker. Granted i don't run it very hard, but i've had it like that for years

You're find, just build / buy an adapter (RV / Boat supply Stores sell them)

-Josh Billings
Logged

Brian Jones

  • Full Member
  • ***
  • Offline Offline
  • Posts: 103
  • Modesto, CA
Re: Electrical safety question
« Reply #15 on: May 19, 2011, 09:11:03 pm »

My thinking is along the lines of what Tim said above. You're dealing with a higher pull, rather than a higher push. The plugging a 20A device into a 30A socket is a no-brainer. However, I am not sure what the risks are of plugging a spec'ed 30A device into a 20A circuit, aside from potentially tripping a breaker. Ergo, I'm asking everyone else!
That is assuming there is a properly rated breaker that is functioning correctly.  The problem would seem to be connecting a device that could try to draw more than the installed wiring and receptacle are rated to support, thus basically creating a situation that relies on what is supposed to be a safety device to provide current limiting during 'normal' use.  If you build an adapter you might include a 20A breaker in it so that what you are connecting can't pull more than 20A and you know that you have a working breaker on the line.

This is a very good idea.

For the record, I use an extension cord with a 15A plug and 20A receptacle when using my iTech8000 which is 20A when at home because I'm plugging into a 20A breaker. I didn't really think about this aspect though... although the breaker is 20A, the wiring and receptacle leading to that breaker aren't necessarily. I guess I should rethink that - although TBH, I don't drive it that hard at home. Nonetheless, looking now for an external breaker solution.
Logged

John Livings

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 351
  • Los Angeles, California
Re: Electrical safety question
« Reply #16 on: May 20, 2011, 12:27:43 am »

Lol I have a PL 6.0 on a 20 amp circuit (15 amp plug) and haven't tripped a breaker. Granted i don't run it very hard, but i've had it like that for years

You're find, just build / buy an adapter (RV / Boat supply Stores sell them)

-Josh Billings

+1, Just test things out Prior to the Gig.

This is running 2-QW-218s @ 8 Ohms or 2-QW-4s @ 8 Ohms with a PL 6.0.II, Plus a rack that has 10 wireless, 1 mixer and a 24 channel recorder.

All on 1- 20 Amp Circuit, Pushing things, 16-17 Amps, 90% of the time, under 10 Amps.

I am talking about 120 Volt, 20 Amp, Single Phase

Just take care of your Equipment.

Regards,  John

http://www.amazon.com/Conntek-14200-1-5-Foot-Pigtail-Connector/dp/B002IZKDHK/ref=sr_1_5?ie=UTF8&qid=1305906445&sr=8-5
« Last Edit: May 20, 2011, 11:49:48 am by John Livings »
Logged

ProSoundWeb Community

Re: Electrical safety question
« Reply #16 on: May 20, 2011, 12:27:43 am »


Pages: 1 2 [All]   Go Up
 



Page created in 0.062 seconds with 22 queries.