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Author Topic: Voltage issue  (Read 5842 times)

Ray Aberle

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Re: Voltage issue
« Reply #10 on: September 05, 2014, 08:42:51 pm »

The nights the other bands have played, there could have been different loading of the electrical service and less voltage swing.  A lack of other complaints could also mean the other bands knew that mentioning it would get no response.

Alternatively, the other bands are idiots and didn't have any problem because they didn't even know enough to look........

-Ray
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frank kayser

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Re: Voltage issue
« Reply #11 on: September 05, 2014, 09:04:39 pm »

Alternatively, the other bands are idiots and didn't have any problem because they didn't even know enough to look........

-Ray
The way I understand a floating neutral problem is sometimes you get lucky, and sometimes you don't. If folks happen to plug in in a  way that keeps both legs +/- 10v, no one is the wiser.  But that can change mid-set when something in the kitchen or an air conditioner kicks in or out. 
frank
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Mike Sokol

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Re: Voltage issue
« Reply #12 on: September 05, 2014, 09:30:12 pm »

The way I understand a floating neutral problem is sometimes you get lucky, and sometimes you don't. If folks happen to plug in in a  way that keeps both legs +/- 10v, no one is the wiser.  But that can change mid-set when something in the kitchen or an air conditioner kicks in or out. 
frank

You'll always remember your first open neutral.  ;D  That's because you'll be paying for the repairs for a  LONG time. Seriously, I've seen entire back-lines taken out when the voltage climbed to 180 volts.

A slightly different cause can be from an undersized neutral in a club that was previously wired for 3-phase industrial power. Many times the POCO would use a smaller neutral to save copper since 3-phase motors don't produce any neutral currents. But in a club with a lot of single-phase loads such as lighting, I've been able to pull the neutral around by 10 or 20 volts just by changing the lighting load on the other phase. If that's indeed the case, then it requires more than tightening a few loose screws, it will need an upgrade by the POCO. You can get an electrician to check for this neutral problem by opening the main service panel and inspecting the incoming wire gauges to make sure they're all sized the same. Don't do this yourself unless you're authorized by the club owner and licensed to open up the panel. There will be live wires inside that also have arc-flash current capabilities. You need to be really careful with this stuff.
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Jamin Lynch

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Re: Voltage issue
« Reply #13 on: September 05, 2014, 09:45:00 pm »

You'll always remember your first open neutral.  ;D  That's because you'll be paying for the repairs for a  LONG time. Seriously, I've seen entire back-lines taken out when the voltage climbed to 180 volts.

A slightly different cause can be from an undersized neutral in a club that was previously wired for 3-phase industrial power. Many times the POCO would use a smaller neutral to save copper since 3-phase motors don't produce any neutral currents. But in a club with a lot of single-phase loads such as lighting, I've been able to pull the neutral around by 10 or 20 volts just by changing the lighting load on the other phase. If that's indeed the case, then it requires more than tightening a few loose screws, it will need an upgrade by the POCO. You can get an electrician to check for this neutral problem by opening the main service panel and inspecting the incoming wire gauges to make sure they're all sized the same. Don't do this yourself unless you're authorized by the club owner and licensed to open up the panel. There will be live wires inside that also have arc-flash current capabilities. You need to be really careful with this stuff.

Me no touchy  ;D

This is not a very large place. I believe it was a convenience store previously.
« Last Edit: September 05, 2014, 09:55:00 pm by Jamin Lynch »
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Stephen Swaffer

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Re: Voltage issue
« Reply #14 on: September 05, 2014, 10:36:35 pm »

Then Mike's suggestion of an undersize neutral might be very possible.  A high percentage of a convenience store's power is refrigeration and commercial refrigeration is often 3 phase, their single phase loads would be relatively light. If it is a small place, a competent electrician should be able to find the problem (and fix it, if it is just loose/corroded) in an hour or 2 at the most-that would be far less costly than replacing gear.

Perhaps if everything is running on universal power supplies it might be ok-but depending the relative locations of the "problem" and the ground/neutral bond it could be a serious safety issue as well.
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Steve Swaffer

Tim McCulloch

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Re: Voltage issue
« Reply #15 on: September 05, 2014, 10:53:58 pm »

Me no touchy  ;D

This is not a very large place. I believe it was a convenience store previously.

I'm liking Mikes undersized neutral hypothesis, especially with Steve's comments added in.
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Tom Bourke

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Re: Voltage issue
« Reply #16 on: September 06, 2014, 09:57:58 pm »

Or a licensed electrician.  Leave the Kryptonite at home, just in case.
Make that a competent licensed electrician. First time I ran into a floating neutral it had burned up a fuse panel.  I had to explain to the kid they sent out how a burned panel could make some lights glow brighter!  It was a four-plex apartment building and the original install had a #14 wire running threw all 4 panels! :o
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Jonathan Johnson

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Re: Voltage issue
« Reply #17 on: September 07, 2014, 01:55:48 am »

If we can't get it fixed, would a voltage regulator do any good? Is there potential for equipment damage or injury?

There is potential for equipment damage. Too high of voltage could case internal arcing or damage to wiring or circuit traces. That in turn could lead to a hot skin condition on equipment. Personnel could receive an electrical shock. (OK, so this is worst-case scenario.)

If you can't get it fixed, you could argue breach of contract -- if your contract specifies electrical requirements. A rider might include something to the effect of "band may require electrical systems to be tested and inspected prior to connection by a licensed electrician at the venue's expense. Any deficiencies shall be corrected at venue's expense prior to connection."
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Stop confusing the issue with facts and logic!

Jeff Bankston

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Re: Voltage issue
« Reply #18 on: September 07, 2014, 05:11:35 am »

Tell 'em to fix it or find someone else.   Hell, call the fire marshall/building inspector.
Just my opinion...
frank
exactly
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Mike Sokol

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Re: Voltage issue
« Reply #19 on: September 07, 2014, 10:55:05 am »

I'm liking Mikes undersized neutral hypothesis, especially with Steve's comments added in.

Any time you see a 3-phase industrial service panel that's been re-purposed for single-phase lighting and amplifier loads, that's the time to be suspicious that the neutral might be sized too small. The POCOs used to do this all the time and it's caught me unawares a few times.
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Mike Sokol
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ProSoundWeb Community

Re: Voltage issue
« Reply #19 on: September 07, 2014, 10:55:05 am »


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