# 20amp to 15amp adapter safety



## ZakkClarkTLB (Oct 2, 2012)

My band just recently bought a dimmer pack(Cyber Elationpak) that has a 20amp plug. I am guessing most venues that we will be traveling to will have 15amp circuits and plugs. Furman has an adapter that has a breaker built-in, so if you draw more than 15amps it will trip its own circuit instead of the venues, in this case. It is UL listed but I want a few more opinions before taking what could be a risk. We will not be maxing out the amps in our dimmer pack or even coming close. We are using 2 65 watt bulbs on two channels and one 65 watt bulb on the other two. Do you think Furmans product would be reliable? I will post a link below. Thanks! 

Furman ADP-1520B 20A to 15A Adapter Power Cable at zZounds

Zakk


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## Footer (Oct 2, 2012)

Its not needed. You won't even be getting close to the maximum load of the circuit. Also, you never have to protect a circuit from overdraw that is rated lower then your load. It is impossible for you to pull too much power from the outlet to fry the wiring in the walls. By putting in that adapter you are just putting in one more failure point.


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## cmckeeman (Oct 2, 2012)

if a venue cant spare 20 amps for your lights then that is a really bad venue, also you are only pulling a little under 200 amps, which is less than 10% of your total power on your dimmer, you could put a peak load of 1800 watts on a 15 amp circuit, so you should be fine with your dimmers even if you have more than just those 3 lights on that circuit. also the only reason to get the furman is so that you don't have to find the house breaker but have your own but you shouldn't ever trip it with that small of a load


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## ZakkClarkTLB (Oct 2, 2012)

Well the problem is that the 20amp plug will not fit into a 15amp outlet. So its not just a power issue it is a compatibility issue


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## gafftapegreenia (Oct 2, 2012)

Cut the plug off and wire on a NEMA 5-15P instead of the 5-20P. You are not loading the pack to anywhere even close to its capacity. This *does* void the UL warranty. Personally I find most factory molded plugs to be of a lower quality, as the hollow ground pins break off rather easily. 

Then, after the gig, if you are worried about other people using it to its capacity, put a 5-20P back on.

But, it it makes you feel safe, buy the adapter.


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## Aman121 (Oct 2, 2012)

Yeah I'd just swap out the plug to a standard edison. But hey, you get allot of points in my book for asking! Allot of people would just go and hack something together without making sure its safe.


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## Chris15 (Oct 3, 2012)

cmckeeman said:


> also you are only pulling a little under 200 amps, which is less than 10% of your total power on your dimmer



Care to recheck that?


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## jonliles (Oct 3, 2012)

> Care to recheck that?




> We are using 2 65 watt bulbs on two channels and one 65 watt bulb on the other two.



(2 Bulbs *65W) *2 Channels + 65W +65W = 390W. A = W/V or 390W/120V = 3.25Amps. 

Either way, you are lower than the rated circuit and the pack.


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## creamers (Oct 3, 2012)

Instead of buying the adapter. I just take a 1Gang box with a duplex outlet and put a pigtail on it to a 15AMP plug. That way you dont ruin the cord with a new end. Though it works either way.


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## headcrab (Oct 3, 2012)

creamers said:


> Instead of buying the adapter. I just take a 1Gang box with a duplex outlet and put a pigtail on it to a 15AMP plug. That way you dont ruin the cord with a new end. Though it works either way.



Until someone punches out a knockout.


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## gafftapegreenia (Oct 3, 2012)

creamers said:


> Instead of buying the adapter. I just take a 1Gang box with a duplex outlet and put a pigtail on it to a 15AMP plug. That way you dont ruin the cord with a new end. Though it works either way.



I would rather do it properly and have a 5-15P on one end and a 5-20R on the other. 

We have had several discussions on the illegality of using a metallic j box for this purpose. There are several plastic products on the market suitable for such use, and I understand how such a cord can at times be desirable. Leviton, O. A. Windsor, and others make such products.

I can't seem to find a link to a low priced option, but I know there exists a small, single piece molded adapter for converting such plugs.


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## JD (Oct 3, 2012)

gafftapegreenia said:


> I would rather do it properly and have a 5-15P on one end and a 5-20R on the other.
> 
> We have had several discussions on the illegality of using a metallic j box for this purpose. There are several plastic products on the market suitable for such use, and I understand how such a cord can at times be desirable. Leviton, O. A. Windsor, and others make such products.
> 
> I can't seem to find a link to a low priced option, but I know there exists a small, single piece molded adapter for converting such plugs.



Kind of in the "Don't cut the cord" camp as well. Once you do you void the warranty and the UL rating on the unit. Almost happy to hear that Elation is actually using the proper plug! I remember that Crown power amps used to come through with the 20 amp plug, but they would also enclose a short adapter cable that took it to a 15 amp plug. That way the power amp maintained it's UL rating. No rating on the adapter tho!


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## gafftaper (Oct 3, 2012)

My vote is for a trip to Home Depot to pick up two plugs and a foot of cable. Make your own 15 to 20 adapter. Store it separate so that someone who doesn't know what they are doing doesn't accidentally come along and load up the dimmer and install the adapter cable.


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## creamers (Oct 3, 2012)

gafftapegreenia said:


> I would rather do it properly and have a 5-15P on one end and a 5-20R on the other.
> 
> We have had several discussions on the illegality of using a metallic j box for this purpose. There are several plastic products on the market suitable for such use, and I understand how such a cord can at times be desirable. Leviton, O. A. Windsor, and others make such products.
> 
> I can't seem to find a link to a low priced option, but I know there exists a small, single piece molded adapter for converting such plugs.



I saw one a few months ago that was around $8 or $10 on sweetwater I think.


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## gafftapegreenia (Oct 3, 2012)

gafftaper said:


> My vote is for a trip to Home Depot to pick up two plugs and a foot of cable. Make your own 15 to 20 adapter. Store it separate so that someone who doesn't know what they are doing doesn't accidentally come along and load up the dimmer and install the adapter cable.



I made one of those for myself a few months ago. The 5-20P alone was almost $10, and that was the cheapest they had! The molded adapter is nearly the same price.


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## creamers (Oct 3, 2012)

Plus you know the AWG # when making it yourself and it can be much much longer. I prefer the 1 gang method due to you get 2 plugs.


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## Edrick (Oct 3, 2012)

Lex has a molded adapter I got it with my e-string you can buy it separately


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## cmckeeman (Oct 3, 2012)

i read it as 3 65 watt lights on the whole pack which would only be 180,


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## Chris15 (Oct 4, 2012)

jonliles said:


> (2 Bulbs *65W) *2 Channels + 65W +65W = 390W. A = W/V or 390W/120V = 3.25Amps.




cmckeeman said:


> i read it as 3 65 watt lights on the whole pack which would only be 180,



Let me requote the original post;

cmckeeman said:


> you are only pulling a little under 200 amps, which is less than 10% of your total power on your dimmer



200 *amps* will vapourise the average shoebox dimmer.
Let us not forget the importance of getting our technical terms correct...


gafftaper said:


> My vote is for a trip to Home Depot to pick up two plugs



I'm surprised Derek has not chastised you for this, but 2 plugs make a suicide adapter, a plug and a socket on the other hand...


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## gafftapegreenia (Oct 4, 2012)

Chris15 said:


> a plug and a socket on the other hand...



socket (receptacle, outlet, jack)?


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## headcrab (Oct 4, 2012)

I think it would be a plug and a connector.
That is, a NEMA5-15P device and a NEMA5-20C device.


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## porkchop (Oct 4, 2012)

To put my 2 cents into the technical discussion I tend to use plug and receptacle.

As far as the pack goes, I personally would go the make or buy an adapter route. FWIW my employer on the other hand says chop off the connector and put a 5-15P on the thing, because when all is done they cost just as much to get fixed as they do to replace (Not my words, theirs). The UL listing of course is an entirely separate story.


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## ship (Oct 4, 2012)

ZakkClarkTLB said:


> My band just recently bought a dimmer pack(Cyber Elationpak) that has a 20amp plug. I am guessing most venues that we will be traveling to will have 15amp circuits and plugs. Furman has an adapter that has a breaker built-in, so if you draw more than 15amps it will trip its own circuit instead of the venues, in this case. It is UL listed but I want a few more opinions before taking what could be a risk. We will not be maxing out the amps in our dimmer pack or even coming close. We are using 2 65 watt bulbs on two channels and one 65 watt bulb on the other two. Do you think Furmans product would be reliable? I will post a link below. Thanks!
> 
> Furman ADP-1520B 20A to 15A Adapter Power Cable at zZounds
> 
> Zakk



If I understand it correctly, the dimmer with a 5-20 plug is being plugged into the Furman. The Furman inside your rack is powering up the system in plugging into the house power which in an industrual situation is normally 5-20 outlet but could be 5-15. The Furman could trip the breaker unless both house and the Furman trip at about the same time as happens, this assuming a 15 Amp breaker in use in an industrial situation which isn't all that common but done.

So far non-starters to the problem, even if 15 AMP plugging into, the Furman is plugging into it not the dimmer. More a question of inside your rack panel to plug something that is correctly plugged into something that is correctly receptacled. Your rack, you are liable - or at least who you work for is liable for it. The rack panel is not provided by the house you are visiting. This is a company you work for question on changing the plug or not as it's their liabilty. This assuming I understand the question correctly.

Within where you work, if you feel it's un-safe for amperage or wiring, certainly there is a problem. Overall if the Furman is the AC distro for your rack, and it's breakered for 15 Amps, it will shut that rack the dimmer is in at that point, if not also if house power is 15 Amps possibly shut it down also. Chance of that dimmer drawing 20 amps on a 15 Amp system - not likely in being shut down before it happens.

This assuming I understand this correctly. And if I do, possible to change the breaker on the dimmer to 15A? Not necessary but a thing that could be done in properly changing it's plug to 15A.


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## porkchop (Oct 5, 2012)

ship said:


> This assuming I understand this correctly. And if I do, possible to change the breaker on the dimmer to 15A? Not necessary but a thing that could be done in properly changing it's plug to 15A.



No Cyber Pak I've ever seen has a breaker, but a small 5A fuse for each of 4 channels. So It's really only even possible to pull more than 15A if you are using all 4 channels.


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## derekleffew (Oct 5, 2012)

ZakkClarkTLB, are you saying that your Elation Cyber Pak came from the manufacturer with a *molded* 5-20P installed? 


Or was it an installed connector:


?

Does the cord say "... SJTW ... 3/C ... 14AWG ..." or "... 12AWG ..."?

There appears to be confusion, even in Elation's manual, on whether it's a 15A or 20A max. pack. From http://www.elationlighting.com/pdffiles/cyber-pak.pdf :



It's almost as if they intentionally do not specify or demonstrate the pack's mains connector.

Either way, I wouldn't use or trust the pack with more than 1800W total, and would have no problem installing a 5-15P. The pack is listed, by NRTL (ETL), so a NEMA 5-15 to 5-20 adapter, either building one's own or the Furman product (which I'd like to see the listing on), is the only choice if one is concerned about maintaining that.

Note that this is not an Elation-specific issue; the topic arises just about every time a dimmer, shoebox is discussed.

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Chris15 said:


> ...I'm surprised Derek has not chastised you for this, but 2 plugs make a suicide adapter, a plug and a socket on the other hand...


Here in the US, we try to avoid using "socket" as a synonym for "receptacle / female / line connector". Sockets take lamps, receptacles take plugs / males / load connector s. Many non-entertainment electricians also take issue with using "receptacle" to mean an inline female device, preferring "connector" to always (well, usually always) mean female, and "plug" to always mean male. 
"Hand me that female plug, will ya?" 
"You mean the cord cap?" 
"No. Cord caps are always male, stoopid!"
.


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