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Author Topic: Overloaded Extension Cords  (Read 10356 times)

Mike Sokol

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Re: Overloaded Extension Cords
« Reply #10 on: January 21, 2014, 10:27:41 pm »

It's even worse than that.  You are using half your power to heat up the speaker cable (instead of heating up voice coils  :( ), but because you've added that extra resistance, the amp is now only putting out about half the power you thought it would.

GTD

You're right... so an amplifier rated for 1,000 watts at 4 ohms would probably only deliver around 250 watts to the speakers on stage. That's a lotta loss...
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Mike Sokol
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Mark Cadwallader

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Re: Overloaded Extension Cords
« Reply #11 on: January 21, 2014, 11:14:26 pm »

You're right... so an amplifier rated for 1,000 watts at 4 ohms would probably only deliver around 250 watts to the speakers on stage. That's a lotta loss...

And thus folks can get away with 4 times RMS ratings without burning out drivers.... 
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Lyle Williams

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Re: Overloaded Extension Cords
« Reply #12 on: January 22, 2014, 01:55:29 am »

We had a drum of flex retained as an educational example if what not to do.  Operated at high current, the insulation had melted and flowed like lava out the bottom of the drum.
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Mike Sokol

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Re: Overloaded Extension Cords
« Reply #13 on: January 22, 2014, 08:30:54 am »

We had a drum of flex retained as an educational example if what not to do.  Operated at high current, the insulation had melted and flowed like lava out the bottom of the drum.

Does anyone have pictures of melted/burned wiring or plugs they can share? If so, post them here...
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Jordan Wolf

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Overloaded Extension Cords
« Reply #14 on: January 22, 2014, 10:57:35 am »

Found - still ON and plugged in - at a show last November, I think.  A gift from the overnight cleaning crew...

I don't know if the image is detailed enough, but the prong was still in the Neutral slot.

My take is that the prong was broken inside the molded plug assembly, causing a arc that totaled the strip (and probably the plug housing, too). The carpet was also singed around where the strip was.
« Last Edit: January 22, 2014, 11:00:37 am by Jordan Wolf »
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Tommy Peel

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Re: Overloaded Extension Cords
« Reply #15 on: January 22, 2014, 11:58:00 am »

I don't have a picture and this isn't audio related but a few years ago we had a '96 F250 Diesel pickup(my family owned it from '99-'12 with 280k+ miles on it when  we sold it). Anyway we had to use the 1500 watt engine block heater on it all winter while we had it and the AC cord that ran from  the grill to the heater wasn't heavy enough. We had to replace the cable once while we owned it and had to replace the plug on the cord every few years because they would overheat and get burnt looking.

Sent from my Nexus 4 running OmniROM 4.4 KitKat using Tapatalk Pro

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Greg_Cameron

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Re: Overloaded Extension Cords
« Reply #16 on: January 22, 2014, 12:48:26 pm »

The market for cheap extension cords makes it hard to buy good ones.  Who wants to buy a $200 extension cord when there is a $20 one at the hardware store?

This is why I make them myself from 12AWG SO cord and good connectors. It's hard to find good off the shelf cords that are both hard service rated and black.
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Mike Sokol

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Re: Overloaded Extension Cords
« Reply #17 on: January 22, 2014, 02:22:50 pm »

This is why I make them myself from 12AWG SO cord and good connectors. It's hard to find good off the shelf cords that are both hard service rated and black.

If you got the $$$, then the WW Power Link stuff is great. I use these to distro between my various FOH processing racks. http://whirlwindusa.com/catalog/power-electrical-distribution/default/power-linktm

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Samuel Rees

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Re: Overloaded Extension Cords
« Reply #18 on: January 22, 2014, 02:37:18 pm »

Just got my PowerCon Quads from Ken at O.A. Windsor and they are excellent!
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Mike Sokol

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Re: Overloaded Extension Cords
« Reply #19 on: January 22, 2014, 04:10:24 pm »

Just got my PowerCon Quads from Ken at O.A. Windsor and they are excellent!

Got pics?
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Mike Sokol
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