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[Debbie Dunkley]

I have couple of fixtures - 77w draw each. The NEMA to Powercon cables that came with them are pretty heavy duty and I'd like to make some lighter weight, shorter cables by using a couple of old IEC cables and cutting off the IEC end and replacing with Powecons but wanted to make sure I haven't overlooked anything that could be a problem.
Over the years I seem to have 'collected' far more IEC cables than I will ever need so it makes sense to repurpose this way.
I made some Powercon cables before this way for subs I owned but they were - and needed to be - heavy duty.

[Dave Garoutte]

I have couple of fixtures - 77w draw each. The NEMA to Powercon cables that came with them are pretty heavy duty and I'd like to make some lighter weight, shorter cables by using a couple of old IEC cables and cutting off the IEC end and replacing with Powecons but wanted to make sure I haven't overlooked anything that could be a problem.
Over the years I seem to have 'collected' far more IEC cables than I will ever need so it makes sense to repurpose this way.
I made some Powercon cables before this way for subs I owned but they were - and needed to be - heavy duty.

I do that a lot.

[David Morison]

I have couple of fixtures - 77w draw each. The NEMA to Powercon cables that came with them are pretty heavy duty and I'd like to make some lighter weight, shorter cables by using a couple of old IEC cables and cutting off the IEC end and replacing with Powecons but wanted to make sure I haven't overlooked anything that could be a problem.
Over the years I seem to have 'collected' far more IEC cables than I will ever need so it makes sense to repurpose this way.
I made some Powercon cables before this way for subs I owned but they were - and needed to be - heavy duty.

The cable used for the original IEC leads will almost certainly be rated for less current than the Powercons. Clearly, that wouldn't be an issue for fixtures with <100W draw.
However, I don't know if that could be a code issue in the US, but at the very least you'd need to remember that those cables do not have the full rating of the Powercon, so that you don't inadvertently try and use them for some higher current application in the future (like your aforementioned subs).
Cheers,
David.

[Debbie Dunkley]

The cable used for the original IEC leads will almost certainly be rated for less current than the Powercons. Clearly, that wouldn't be an issue for fixtures with <100W draw.
However, I don't know if that could be a code issue in the US, but at the very least you'd need to remember that those cables do not have the full rating of the Powercon, so that you don't inadvertently try and use them for some higher current application in the future (like your aforementioned subs).
Cheers,
David.

Thank you Dave and David - this is what I needed to know. I will certainly make sure to never use those cables for anything rated much higher than the fixtures. I don't even own anything else that requires Powercon cables anymore.

[Brian Jojade]

Yes, very easy to do.  Hack off the IEC, attach a powercon.  Done.

Of course, just like with IEC cords, it's important to pay attention to the gauge of the wire and the intended use, or you'll be in for a surprise. 

One thing to be cautious about though is to meter the wires to make sure you're wiring them correctly.  The internal color codes may not match US standards, or in some cases not match any standards at all...  Yes, I've run into IEC cords where the internal green piece of wire is tied to the hot leg.  Good times.

[Debbie Dunkley]

Yes, very easy to do.  Hack off the IEC, attach a powercon.  Done.

Of course, just like with IEC cords, it's important to pay attention to the gauge of the wire and the intended use, or you'll be in for a surprise. 

One thing to be cautious about though is to meter the wires to make sure you're wiring them correctly.  The internal color codes may not match US standards, or in some cases not match any standards at all...  Yes, I've run into IEC cords where the internal green piece of wire is tied to the hot leg.  Good times.

Thanks Brian - Yes, I'd never just assume... I will test continuity end to end pre and post wiring.

[Patrick Tracy]

I know you can buy an IEC C14 to Powercon cable. I'm not sure it's a particularly good idea, but they exist. I'm bringing it up because if it's a bad idea, someone here is bound to know and say so, which would be useful information.

[Erik Jerde]

Yes, very easy to do.  Hack off the IEC, attach a powercon.  Done.

Of course, just like with IEC cords, it's important to pay attention to the gauge of the wire and the intended use, or you'll be in for a surprise. 

One thing to be cautious about though is to meter the wires to make sure you're wiring them correctly.  The internal color codes may not match US standards, or in some cases not match any standards at all...  Yes, I've run into IEC cords where the internal green piece of wire is tied to the hot leg.  Good times.

If the IEC cable is short enough a smaller wire gauge really isn’t going to be an issue.  My 50A oven has at most 14ga wire internally and hasn’t had a single problem.  It’s such a short run that voltage drop across it is still less than 3% IF a full 50A was being pulled (unlikely). Now an oven is a manufactured and tested product and I don’t suggest running 50A down a 14ga wire.  However a short jump from stringer to device in open air is unlikely to cause any issue.  The breaker should trip before enough current flowed to cause a problem.

[Kemper Watson]

I have couple of fixtures - 77w draw each. The NEMA to Powercon cables that came with them are pretty heavy duty and I'd like to make some lighter weight, shorter cables by using a couple of old IEC cables and cutting off the IEC end and replacing with Powecons but wanted to make sure I haven't overlooked anything that could be a problem.
Over the years I seem to have 'collected' far more IEC cables than I will ever need so it makes sense to repurpose this way.
I made some Powercon cables before this way for subs I owned but they were - and needed to be - heavy duty.

I've done this a lot. I often find the wrong color wire inside the  cables. I've also come across those with Hot/neutral reversed . Always use a meter to confirm the hot leg

[Debbie Dunkley]

Thanks guys…

[Brian Jojade]

If the IEC cable is short enough a smaller wire gauge really isn’t going to be an issue.  My 50A oven has at most 14ga wire internally and hasn’t had a single problem.  It’s such a short run that voltage drop across it is still less than 3% IF a full 50A was being pulled (unlikely). Now an oven is a manufactured and tested product and I don’t suggest running 50A down a 14ga wire.  However a short jump from stringer to device in open air is unlikely to cause any issue.  The breaker should trip before enough current flowed to cause a problem.

Your typical large heating element in an oven is about 2500 watts.  At 240 volts, that's just over 10 amps.  Each element is on its own run back to that main 50 amp source which is why they can safely use 14 gauge wire internally.  Of course, if you had some sort of partial failure of an element that increased the current draw, there is risk that the internal cable could start on fire.  That sort of failure is nearly impossible without modification, so it's considered acceptable.  Even still, some devices will have additional circuit breakers or fuses on each element just in case.

While you won't see much voltage drop over a short piece of wire, voltage drop means heat is being generated in the wire.  If you run 20 amps through a 6 foot piece of #18 wire, you would see a 3% voltage drop. That works out to 13 watts of heat dissipated per linear foot of wire.

In comparison, the same voltage drop on a piece of #12 would need a 25 foot cable to have a similar voltage drop, which works out to about 3 watts per foot.

At 20 amps, that #12 is going to get warm.  If you coil up the #12, or bundle a whole bunch of cables with the same draw together so that the heat can't escape, it could eventually melt.

A piece of #18 at 20 amps will get VERY hot in open air.  Hot enough that it will likely melt the internal wires and once those get soft, any movement of the wire can cause a short.  ie, hot wire, someone bumps it, and that's when the short would happen.  If it sits untouched, it could get melty, but not quite enough to short out if there's no stress on the internal components.

A breaker won't do anything to prevent this until it does short out, and then hopefully the breaker trips. 

Just a recipe for disaster if you don't pay attention!

[Steve-White]

Interesting quandary.  Debbie this would probably be best served in the AC Power and Grounding forum.

Lots of things to consider here.

[Debbie Dunkley]

Interesting quandary.  Debbie this would probably be best served in the AC Power and Grounding forum.

Lots of things to consider here.

Possibly but I think I have my answer - I really just wanted to see if others have encountered any issues doing this.

[Steve-White]

Those type cords are typically 16ga with a 15A Edison plug on them.  Using them on a stage you will want to be sure from a NEC/liability perspective to cover yourass.

[Craig Hauber]

Possibly but I think I have my answer - I really just wanted to see if others have encountered any issues doing this.

One fun thing I did years ago was taking 4 of the 18-ga IEC cables and fitting them all into a single Hubbel male edison.  That way I could neatly run 4 of the lights off just one connection without cube-taps or power strips (they were all IEC and did not have loop outs).  I even used different length IEC's so the cords hung nice and tidy with minimal excess slack loops.
I doubt it was at all in any way code acceptable but it survived a couple theater tours (where I was the only one handling it). 

[ProSoundWeb Community]