ProSoundWeb Community

Please login or register.

Login with username, password and session length
Advanced search  

Pages: 1 2 [3] 4 5   Go Down

Author Topic: GFCI advice please  (Read 11464 times)

Scott Wagner

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 1020
  • Richmond, VA
Re: GFCI advice please
« Reply #20 on: June 14, 2015, 10:36:47 pm »

Just stumbled across this thread while looking for info as to why my Itech 8k kept tripping the GFI yesterday.

I have 2 reoccurring gigs that are outdoor venues, and they are the only places that have GFI's (I'm guessing it's required for outdoor outlets?).
At both places, my Itech 8K trips the GFI.  I'm using it on JBL SRX subs. 
At one of the venues I swapped out to an XTI4k (and just ran one SRX728), and that also tripped the GFI.
I guess I could also try my CE4000....but could I even expect any different result?

What is the solution here?  Less gear?  Because I know these venues are not going to make any changes to accommodate.

I may give Crown a call to see if I can learn anything.
Sounds like a faulty GFCI to me. They DO go bad from time to time (much more often than a standard outlet). If it's a repeat gig, have them change the GFCI with a new one. If it trips after that, the problem is in the amplifiers.
Logged
Scott Wagner
Big Nickel Audio

Stephen Swaffer

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 2382
Re: GFCI advice please
« Reply #21 on: June 15, 2015, 11:55:35 am »

I agree that it may well be a faulty GFCI.  I would get them to replace the GFCI, but rather than leave to chance tripping during another gig, set up the system on a known good GFCI (even a GFCI  protected cord/power strip would work) to make sure the problem is not your gear-would even give you a stronger case to argue for replacement on their end. 
Logged
Steve Swaffer

Mark Wilkinson

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 1019
Re: GFCI advice please
« Reply #22 on: June 15, 2015, 12:59:14 pm »

Sorry,....... are we talking tripping receptacles or breakers?

I asked because I have not found a GFI receptacle that I can not make trip with a qsc plx 3402 , pl340, or rmx 4050.
Any of these amps in bridge mode, on very big peaks to a sub, have popped all the GFCI receptables I've tried.

But I've never had a problem since ditching the receptacles for breakers....

Dunno..................possible reasons?
Logged

John Roberts {JR}

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 16639
  • Hickory, Mississippi, USA
    • Resotune
Re: GFCI advice please
« Reply #23 on: June 15, 2015, 01:50:39 pm »

I asked because I have not found a GFI receptacle that I can not make trip with a qsc plx 3402 , pl340, or rmx 4050.
Any of these amps in bridge mode, on very big peaks to a sub, have popped all the GFCI receptables I've tried.

But I've never had a problem since ditching the receptacles for breakers....

Dunno..................possible reasons?

I too am curious about this. The typical GFCI spec is 5 mA and these amps are probably not leaking this much. Most mains wiring and outlets are rated for average power, and music is an average power thing... BUT some big dog amps may put serious current spikes on the mains that might saturate the GFCI's sensitive magnetic circuit.

I found some data for RCDs that suggests they will handle 1000A peaks but I did not find a similar spec for cheap US GFCI. An LxC filter in the line may fix that, or a different GFCI..

This is still a guess and I would want to ask the amp manufacturers who will have heard about this if it is a common problem.

JR
Logged
When in doubt do what's right.

Rob Spence

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 3484
  • Boston Metro North/West
    • Lynx Audio Services
Re: GFCI advice please
« Reply #24 on: June 15, 2015, 04:34:50 pm »

I too am curious about this. The typical GFCI spec is 5 mA and these amps are probably not leaking this much. Most mains wiring and outlets are rated for average power, and music is an average power thing... BUT some big dog amps may put serious current spikes on the mains that might saturate the GFCI's sensitive magnetic circuit.

I found some data for RCDs that suggests they will handle 1000A peaks but I did not find a similar spec for cheap US GFCI. An LxC filter in the line may fix that, or a different GFCI..

This is still a guess and I would want to ask the amp manufacturers who will have heard about this if it is a common problem.

JR

Hmm, pretty much most of my amps are PLX3402s but never in bridge mode and never trips GFCIs even with 3 amps per circuit.

In the U.S., outdoor outlets are required to be GFCI protected so get used to it.



Sent from my iPad using Tapatalk HD
Logged
rob at lynxaudioservices dot com

Dealer for: AKG, Allen & Heath, Ashley, Astatic, Audix, Blue Microphones, CAD, Chauvet, Community, Countryman, Crown, DBX, Electro-Voice, FBT, Furman, Heil, Horizon, Intellistage, JBL, Lab Gruppen, Mid Atlantic, On Stage Stands, Pelican, Peterson Tuners, Presonus, ProCo, QSC, Radial, RCF, Sennheiser, Shure, SKB, Soundcraft, TC Electronics, Telex, Whirlwind and others

Lyle Williams

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 1556
Re: GFCI advice please
« Reply #25 on: June 15, 2015, 04:56:01 pm »

You guys need to find a way to use RCD/GFCI with more sensible trip currents.

Find a rule that allows bigger trip currents, or get your electrical rules changed.
Logged

Jay Marr

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 669
Re: GFCI advice please
« Reply #26 on: June 15, 2015, 07:14:50 pm »

You guys need to find a way to use RCD/GFCI with more sensible trip currents.

Find a rule that allows bigger trip currents, or get your electrical rules changed.

Can you explain a bit more of what you mean?
I want to understand what the possible solutions are.
Thank you.
Logged

Jay Marr

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 669
Re: GFCI advice please
« Reply #27 on: June 15, 2015, 07:25:28 pm »

Ok folks, well I called Crown a few minutes ago.

They said it's very common for the iTech 8k to trip the GFI Receptacle because of the amount of ground leakage that the amps have.
I should have written down the amount of leakage he told me it had, but it seems that the Engineers at Crown had to calculate this on the iTech 8k's because lots of folks were tripping GFI receptacles. 
This made me feel better that it's not a problem with my amp....but this does not help with these 2 venues where I trip the receptacle.
Both venues, I have tried multiple circuits (which all have GFI's), and I have the same result....so the suggestion that it is a bad GFI receptacle, does not seem to be the case.

I asked about the leakage on a CE4000, because I could always use two CE4k's instead of one iTech 8k (and put the CE4k's on different circuits).
The support resource (who was really helpful) is going to ask the Engineers if they have a leakage value on the CE4k's.
I'll post those results here when I get them, in case anyone is interested.
Logged

John Roberts {JR}

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 16639
  • Hickory, Mississippi, USA
    • Resotune
Re: GFCI advice please
« Reply #28 on: June 15, 2015, 07:31:14 pm »

You guys need to find a way to use RCD/GFCI with more sensible trip currents.

Find a rule that allows bigger trip currents, or get your electrical rules changed.

I am not a fan of dramatically increasing the trip currents. Humans can experience muscular contraction at low tens of mA so 5mA GFCI threshold seems safe and should be easily reached by modern product design (except maybe by Crown).

People need to just throw away all the cheesy outlet strips that leak due to dodgy spike arrestors.

Crown needs to get their act together if the trip is actual leakage from the mains circuit in excess of 5 mA.

JR
Logged
When in doubt do what's right.

Ed Walters

  • Full Member
  • ***
  • Offline Offline
  • Posts: 191
  • Holland, MI, USA
Re: GFCI advice please
« Reply #29 on: June 15, 2015, 07:31:49 pm »

An LxC filter in the line may fix that, or a different GFCI..

I've run into GFCI's that will trip from the RF hash of a household dimmer on a different circuit. I've tripped a few at home and at other places, with ham radio transmissions.

I'm betting that you're on the right path.  Those who are popping GFCI's with big SMPS amps may want to try a real line filter...

Ed Walters
Logged
The Solution LLC: certified: AMX, Audio Architect, Composer, ControlSpace, CTS, DanteL3/DDM, Tesira, and more.

ProSoundWeb Community

Re: GFCI advice please
« Reply #29 on: June 15, 2015, 07:31:49 pm »


Pages: 1 2 [3] 4 5   Go Up
 



Page created in 0.065 seconds with 22 queries.