125v and 250v in the same cord assembly

[Nycedreemz]

I was speaking to a friend of mine who was in need of a locking generator cord. Well being the nice guy that i am i offered to assemble him the L14-30 cord he needed. When i got his cord assembled and brought it home from work to give to him, he looked at it and asked about the 125v/250v rating stamp on the plug and connector end. I explained to him how the four prong L14 series plugs, connectors ect. are able to be wired with a 125v or 250v output. I didnt think much of it then but now i have this burning in my brain. I have never seen this before and have spent quite some time searching. I would like to get a few opinions on this if possible. Lets just say you have a three way three conductor splitter cord, the plug end will be an L14-30P and the two connector ends would be one L5-30R connector and one L6-30R connector. Utilizing both of the L14-30P's voltage capabilitys within one cord assembly. I have assembled this myself by terminating 2 hots and a ground into the L14-30P for the L6-30R, double tapped the one hot, tapped the unused nuetral, and shared the ground into the same L14-30P for the L5-30R connector and tested the output at each connector with them testing correctly. My meter shows 125ish volts 30A at the L5-30R and 250ish volts 30A at the L6-30R. This however has not been tested with both connectors under a load. Only one at a time. Now im am completly aware that a typical residential service is 250v. Im just curious if anybody has ever seen or heard of this kind of splitter cord setup ever. I like the idea of having the ability to utilize either of the voltages possible. My concerns are what may happen if both are placed under load at the same time. Good Idea:thumbsup:? Bad Idea:thumbsdown:? Thanks in advance for anybody input or thoughts.

 

[Nycedreemz]

A small edit to my original post

A small edit to my original post

"Lets just say you have a three way three conductor splitter cord" What i meant to say instead of this is..........I'm going to terminate two separate lengths of 3 conductor cable in one L14-30P. One will terminate to one hot (black), the neutral(white), and the ground(green) this will be feeding a (125v) L5-30R connector. With the other 3 conductor cable i will terminate to each of the hots (black and white) and the ground will be shared between both of them. This will be feeding a (250v) L6-30R connector. Does anybody think this would be a problem to run simultaneously or should they only be placed under a load independently?

 

[GoldDigger]

I was speaking to a friend of mine who was in need of a locking generator cord. Well being the nice guy that i am i offered to assemble him the L14-30 cord he needed. When i got his cord assembled and brought it home from work to give to him, he looked at it and asked about the 125v/250v rating stamp on the plug and connector end. I explained to him how the four prong L14 series plugs, connectors ect. are able to be wired with a 125v or 250v output. I didnt think much of it then but now i have this burning in my brain. I have never seen this before and have spent quite some time searching. I would like to get a few opinions on this if possible. Lets just say you have a three way three conductor splitter cord, the plug end will be an L14-30P and the two connector ends would be one L5-30R connector and one L6-30R connector. Utilizing both of the L14-30P's voltage capabilitys within one cord assembly. I have assembled this myself by terminating 2 hots and a ground into the L14-30P for the L6-30R, double tapped the one hot, tapped the unused nuetral, and shared the ground into the same L14-30P for the L5-30R connector and tested the output at each connector with them testing correctly. My meter shows 125ish volts 30A at the L5-30R and 250ish volts 30A at the L6-30R. This however has not been tested with both connectors under a load. Only one at a time. Now im am completly aware that a typical residential service is 250v. Im just curious if anybody has ever seen or heard of this kind of splitter cord setup ever. I like the idea of having the ability to utilize either of the voltages possible. My concerns are what may happen if both are placed under load at the same time. Good Idea:thumbsup:? Bad Idea:thumbsdown:? Thanks in advance for anybody input or thoughts.

The 125/250 does not mean one or the other, It means no more than 125 volts to ground and no more than 250 volts between conductors.
You meet that limitation.

 

[Nycedreemz]

The 125/250 does not mean one or the other, It means no more than 125 volts to ground and no more than 250 volts between conductors.
You meet that limitation.

By meeting that limitation, with both the L5-30 125v and the L6-30 250v under load at the same time I myself see no reason that this type of assembly should not operate normally. I have never seen a power cord offer the dual volt capability within one assembly. My goal is to provide a customer with this and eliminate the need for purchasing two different extension cords. Using the L14-30P as the source and feeding both voltages i think that solves the problem of a customer not having 125v and 250v in the same location. For instance, say a server rack that has a UPS system and the small equipment is 125v and the UPS requires 250v. Now you can power this entire rack with one extension assembly. (Provided the demand of the equipment does not exceed the rating of the extension itself.) This is of course something that will never be a UL Listed product.

 

[kwired]

By meeting that limitation, with both the L5-30 125v and the L6-30 250v under load at the same time I myself see no reason that this type of assembly should not operate normally. I have never seen a power cord offer the dual volt capability within one assembly. My goal is to provide a customer with this and eliminate the need for purchasing two different extension cords. Using the L14-30P as the source and feeding both voltages i think that solves the problem of a customer not having 125v and 250v in the same location. For instance, say a server rack that has a UPS system and the small equipment is 125v and the UPS requires 250v. Now you can power this entire rack with one extension assembly. (Provided the demand of the equipment does not exceed the rating of the extension itself.)

The cord doesn't "offer" the dual voltage capability, the source (generator) does, the cord simply extends the terminals from the source.

We have the same thing at every service entrance .

 

[Nycedreemz]

The cord doesn't "offer" the dual voltage capability, the source (generator) does, the cord simply extends the terminals from the source.

We have the same thing at every service entrance .

Right on, i get that the cord does not "offer" the dual volt capability. The voltage is provided by how the L14-30 plug is wired. You can wire this at 125v or 250v or both, my goal was to provide both of these voltages with two separate cord whips out of one L14-30 Plug. One three wire cord wired at 125v (L5-30R) and one three wire cord wired at 250v (L6-30R). One of the hots will power the 125v and one side of the 250v. The other hot is of course the second leg of the 250v side. Then the both grounds together with the neutral being there only for the 125v side of the splitter. I'm taking a four wire plug and splitting off into two three wire connectors. Each one feeding one of the voltages that the L14-30P can provide. I have done this with other power cord assemblies. (For instance i can take a three phase L21-30P 120v/208v and wire three single phase L6-30R's onto one plug. This will provide three single phase 208v outputs. You achieve this by tapping (X,Y) Phase 1, (Y,Z) Phase 2, and (Z,X) Phase 3. You drop the neutral all together and all three grounds tap the center lug). If you were to assemble in order to provide 120v you would omit using a second hot and just wire each of the three whips with one of the three phases and of course grounds are shared and neutrals are shared. I was just curious what some would think about a cord assembly that provided both 125v and 250v at the same time within one splitter assembly from one source. Whether it be a generator or a hard wired L14-30 receptacle in a commercial or industrial setting somewhere.

 

[iwire]

Electrically it will work fine, I think you know that.

Code wise the only thing I see are listing and use issues depending on how you make the split.

For instance are you leaving one male plug with two sets of cables?

Or are you using a male plug with a single cable whip to a j-box and split it into two cables there?

You see what I am getting at?



By the way, hit the 'ENTER' key once in a while, it makes it easier to read.

 

[Nycedreemz]

Sorry about that, I will definitely get in the habit of using that enter key. I tried to upload an image of the assembly, however my internet leaves much do be desired in terms of speed so..........

I will be leaving the L14-30P with two separate three wire cables.

One will be the 125v L5-30R connector. The cable will have a black, white and a green. This will be wired of course in the fashion of a 125v circuit. (one hot, one ground, and one neutral).

One will be the 250v L6-30R connector. The cable will have a black, white and a green. This will be wired like a typical single phase 250v circuit. (Two hots and one ground).
With a closed cable assembly we don't re-identify the the white conductor.

I know that this will never be a "UL Listable" item but in the power cord industry we technically can provide customers whatever they request if we consider the assembly to be

1. Safe for the customer to handle
2. Safe and the correct load for the equipment to be supplied
3. Assembled in accordance with NEC
4. Passes our in house Hi-pot, Continuity, and Polarity tests

Not necessarily in that order just those are our main concerns with providing custom cord assemblies. Thanks for your input on the subject, i enjoy a little electrical brainstorming with other people in the field.

 

[GoldDigger]

Sorry about that, I will definitely get in the habit of using that enter key. I tried to upload an image of the assembly, however my internet leaves much do be desired in terms of speed so..........

I will be leaving the L14-30P with two separate three wire cables.

One will be the 125v L5-30R connector. The cable will have a black, white and a green. This will be wired of course in the fashion of a 125v circuit. (one hot, one ground, and one neutral).

One will be the 250v L6-30R connector. The cable will have a black, white and a green. This will be wired like a typical single phase 250v circuit. (Two hots and one ground).
With a closed cable assembly we don't re-identify the the white conductor.

I know that this will never be a "UL Listable" item but in the power cord industry we technically can provide customers whatever they request if we consider the assembly to be

1. Safe for the customer to handle
2. Safe and the correct load for the equipment to be supplied
3. Assembled in accordance with NEC
4. Passes our in house Hi-pot, Continuity, and Polarity tests

Not necessarily in that order just those are our main concerns with providing custom cord assemblies. Thanks for your input on the subject, i enjoy a little electrical brainstorming with other people in the field.

My main concern would be whether the plug is rated by the manufacturer to allow two wires per terminal and two cords in the strain relief. I doubt that, which is why you typically see this sort of adapter/connector made with a molded assembly or a junction box.

Your item 3....

 

[Nycedreemz]

My main concern would be whether the plug is rated by the manufacturer to allow two wires per terminal and two cords in the strain relief. I doubt that, which is why you typically see this sort of adapter/connector made with a molded assembly or a junction box.

Your item 3....

I absolutely understand the need to stay within the manufacturers guidelines in regards to max wire size on terminal and max# of wire in strain relief. We like to stay within the guidelines of the

NEC as well. Our way around some of this is to disclose to the customer that the assembly is not a listed item and we are providing an assembly at their request. That does not mean im in the

business of giving a customer something unsafe or hazardous. In all honesty there's quite a grey area in regards to power cord resellers and its kind of a nightmare to even get UL attention and recognition.

Then when you think you may have stumbled on a pretty sweet design, you find that customers love it, and the powers that be love to put up that brick wall so you can't move any further

with it. I could possibly go the J-box route with it and should be fine. Its just in tight spaces like server racks tend to get along with as little wire per connection as possible due to the fact

that there is usually a rats nest of com cables inside them anyway. Just trying to "think thin" on the design.

 

[kwired]

I absolutely understand the need to stay within the manufacturers guidelines in regards to max wire size on terminal and max# of wire in strain relief. We like to stay within the guidelines of the

NEC as well. Our way around some of this is to disclose to the customer that the assembly is not a listed item and we are providing an assembly at their request. That does not mean im in the

business of giving a customer something unsafe or hazardous. In all honesty there's quite a grey area in regards to power cord resellers and its kind of a nightmare to even get UL attention and recognition.

Then when you think you may have stumbled on a pretty sweet design, you find that customers love it, and the powers that be love to put up that brick wall so you can't move any further

with it. I could possibly go the J-box route with it and should be fine. Its just in tight spaces like server racks tend to get along with as little wire per connection as possible due to the fact

that there is usually a rats nest of com cables inside them anyway. Just trying to "think thin" on the design.

You are welcome to build what you want, chances are what you are building is not "premises wiring" and likely is not covered by local codes. That said, if someone is injured or killed by your product and you did not build it according to recognized standards, a judge or jury will not have much mercy on you, just keep that in mind.

 

[Nycedreemz]

You are welcome to build what you want, chances are what you are building is not "premises wiring" and likely is not covered by local codes. That said, if someone is injured or killed by your product and you did not build it according to recognized standards, a judge or jury will not have much mercy on you, just keep that in mind.

Definitely understand that, this was just a brainstorm on the "possibilities" of some of this dual voltage stuff anyway. Not at all in the business of creating a risk that can hurt someone. Just thinking.

 

[GoldDigger]

Definitely understand that, this was just a brainstorm on the "possibilities" of some of this dual voltage stuff anyway. Not at all in the business of creating a risk that can hurt someone. Just thinking.

Basically, all you need to keep in mind, then, is that the plug and socket you referenced could be used to provide a single 120V circuit at the nominal amperage, one 240V circuit at the nominal amperage, or two 120V circuits each at the nominal amperage.
You just have to be careful if you make it easy for the user to connect both 120V and 240V loads at the same time without adding up the amperages or distributing the 120V loads across both phases. For this reason, you are more likely to see adapters to one type of receptacle or the other rather than both.
Other than the extra cost for the more expensive connectors, using a single cord with twist-lock on both ends and then adding the right adapter to the far end is a more commonly seen way of stocking just one long cord.
There should be no harm done if they do connect too much simultaneously, but it will probably trip the overcurrent protection at the source.

 

[templdl]

It certainly appears that you are within the rating of the plug. But as I scanned the responses what I was looking for is the thebplug is intended to be plugged into a receptacle and that's what my concern is. The configuration is such that the plug is intended to be plugged into a standard voltage receptacle such as 120/240,1ph3w w/gr.as an example. Personally, if I chose to use a different circuit configuration the are within the rating of the plug and receptacle for a custom project I wouldn't be concerned if I have control over the receptacle and plug.
What would run up a red flag is if someone took my device and plugged it into a receptacle that was wired forv120/240, 1ph3w w/grd. Or, if someone were to plug into a receptacle expecting it to be a standard 120/240, 1ph3w w/grd receptacle.
In my personal work shop I'm using plugs and recepcles that are rated 3Ph3w w/grd. They are dedicated to my shop for personal use and there is no chance for someone to plug in a 3ph machine into one of my receptacles or that any of my machines would be plugged into a 3pf source.
As such don't overlook a possible mismatch of the devices and receptacles. If you can assure the the your install is secure and not subject to being misused go for it.

 

[GoldDigger]

What would run up a red flag is if someone took my device and plugged it into a receptacle that was wired forv120/240, 1ph3w w/grd. Or, if someone were to plug into a receptacle expecting it to be a standard 120/240, 1ph3w w/grd receptacle.

I am sure you meant to say something different there, but I am not sure exactly what.
To me 120/240 single phase and 240/120 single phase are the same thing, even though one description is not as common or "correct" as the other.

http://www.stayonline.com/reference-nema-locking.aspx

The L14-30 is a four wire configuration of which one must be used as the EGC. The other three are identified by metal color as two hots and a neutral/grounded conductor.
So this configuration is not intended or allowed to be used for three-phase at any voltage (except maybe for 125 volt corner grounded delta if you could find one) since none of the terminals are rated for more than 125 volts nominal to ground.
Most complete descriptions of the configuration actually say 125/250 volt single phase 3 wire plus ground, although I have not looked directly at the NEMA documents.

So, your otherwise reasonable concern about three phase would only be real if somebody misused this configuration for three phase. In which case you could make the same objection to supplying any kind of twist lock adapter.
I also have noticed that this particular configuration is common for split-phase generators in the applicable current/power range. For smaller generators, the L14-20 serves the same purpose.

PS: For three phase, the L15 through L23 configurations are what is used, either as delta plus ground (4 wire) or wye plus ground (5 wire)

 

[templdl]

I am sure you meant to say something different there, but I am not sure exactly what.
To me 120/240 single phase and 240/120 single phase are the same thing, even though one description is not as common or "correct" as the other.

http://www.stayonline.com/reference-nema-locking.aspx

The L14-30 is a four wire configuration of which one must be used as the EGC. The other three are identified by metal color as two hots and a neutral/grounded conductor.
So this configuration is not intended or allowed to be used for three-phase at any voltage (except maybe for 125 volt corner grounded delta if you could find one) since none of the terminals are rated for more than 125 volts nominal to ground.
Most complete descriptions of the configuration actually say 125/250 volt single phase 3 wire plus ground, although I have not looked directly at the NEMA documents.

So, your otherwise reasonable concern about three phase would only be real if somebody misused this configuration for three phase. In which case you could make the same objection to supplying any kind of twist lock adapter.
I also have noticed that this particular configuration is common for split-phase generators in the applicable current/power range. For smaller generators, the L14-20 serves the same purpose.

PS: For three phase, the L15 through L23 configurations are what is used, either as delta plus ground (4 wire) or wye plus ground (5 wire)

In trying to keep this very simple and it appears as though this topic is getting beat to death and I may not have made my point clear, the issue here is the real possibility of a misapplication, that is the mismatch of the voltage available at the receptacal and what is expected by the plug. Very simple. A dicertation on different pugs is irrelavent as I'm sure every plug could easily be applied at 480v except for the designation on the plug and receptacle themselves as would be evident from their constraction and each having a unique twist lock configuration. What you wouldn't want to do this to use an EGC for a line or neutral. And you may get into a gray area whe it come to art 110 in the code. I'm sure that the OP is chuckling at the rabbit rptrails that have been created.
The very simple point that I'm making to the OP is the possibility for his assembly to be mismatched to either be inadvertantly being plugged into receptacle being supplied in a convention way or someone plugging on their equipment into a receptacle that the OP configured and supplied for his unique application. My concern is the possibility of a mismatch. If the OP has a secure enough facility that the possibility is slim to none like I pointed out using my person workshop as an example then he shouldn't be concerned. I used the plugs and receptacles that I had available because they didn't cost me anything. Those darned things are very expensive.
Also be it 120/240 or 240/120 1ph3w that is dependent upon how the secondary winding(s) of the transformer which is irrelavent regarding this topic. These designations tell me how my customer wants the transformer that I'm building for him wound
And the various NEMA plug configurations is irrelevant also as the OP is using a custom voltage configuration. I'm well aware of of what the various configuration are intended for but as I understand the OPs application is not conventional. JJ

 

[GoldDigger]

I'm well aware of of what the various configuration are intended for but as I understand the OPs application is not conventional. .

The original use the OP provided a cord for seems to have been conventional, and in fact for a generator.
The OP's speculation beyond that seems to me to be about providing a single cord which would serve to adapt that generator outlet, or something like it, to either a 120 or a 240V load. Which is no different in my mind to providing just one or more adapters to plug into that same generator receptacle.

I was speaking to a friend of mine who was in need of a locking generator cord.

I suspect that cord was a straight through L14-30P to L14-30S, which would not be a hazard regardless of the way the source L14 happened to be wired.

I do not see anything about the OP's plan that would put the end user at any greater risk than a commercially available UL-listed adapter with the same L14-30P on one end and only one of the two possible types of non-locking receptacle at the other end.
Now there could be some questions about putting one or more 15A or 20A receptacles at the end of what might be a 30A capable source, but that has been beaten to death elsewhere. The cord itself could be built and rated for any ampacity as long as it is properly labelled. We often plug 6A extension cords into 20A receptacles.

 

[kwired]

I am sure you meant to say something different there, but I am not sure exactly what.
To me 120/240 single phase and 240/120 single phase are the same thing, even though one description is not as common or "correct" as the other.

http://www.stayonline.com/reference-nema-locking.aspx

The L14-30 is a four wire configuration of which one must be used as the EGC. The other three are identified by metal color as two hots and a neutral/grounded conductor.
So this configuration is not intended or allowed to be used for three-phase at any voltage (except maybe for 125 volt corner grounded delta if you could find one) since none of the terminals are rated for more than 125 volts nominal to ground.
Most complete descriptions of the configuration actually say 125/250 volt single phase 3 wire plus ground, although I have not looked directly at the NEMA documents.

So, your otherwise reasonable concern about three phase would only be real if somebody misused this configuration for three phase. In which case you could make the same objection to supplying any kind of twist lock adapter.
I also have noticed that this particular configuration is common for split-phase generators in the applicable current/power range. For smaller generators, the L14-20 serves the same purpose.

PS: For three phase, the L15 through L23 configurations are what is used, either as delta plus ground (4 wire) or wye plus ground (5 wire)

Something tells me that the construction of many/most of the plugs is similar enough that all of them can take application of at least 600 volts. They only have different "labeled" configurations for the purpose of having standards and preventing interchanging for the purpose of protecting the connected equipment from the wrong voltage more so than applying a voltage to the plug that it can not handle.

 

[Nycedreemz]

I am thrilled and a little surprised the subject took off the way it did. Heres how it all started, I provided a friend if mine a Locking 14-30 generator cord for his own generator. Upon his examining the cord against the cord that he purchased at a big box store, he was curious about the rating stamp on the L14-30P and the L14-30R which read 125v/250v

I explained to him how it can be assembled to provide 125v max or 250v max. Later i began to think about it a bit and decided to expirement a little myself.

I terminated two individual 3wire soow cables into the L14-30P and wired one 250v (L6-30R) and the other 125v (L5-30R). This was simple enough to do even though the device has termination limits on the poles as well as max diameter cable in the strain relief.

I hardwired a ROJ (removed outer jacket) cord into my panel on a 250v breaker at my service with a L14-30R to feed my little custom assembly. After testing each end of my nifty little splitter i found the proper voltage present at each connector. 118v at the L5-30R and 236v at the L6-30R. Now this of course was under no load whatsoever so..........

My idea behind it was to feed 125v/250v equipment within a server rack from one source. A single rack fed with one whip that served both of those demands.

I have done this with an L21-30P feeding three L6-30R's, however that assembly has all three connectors at 208v single phase output from a three phase 120v/208v source. This was all just speculative spitballing and no need to create a "Whos got the bigger brain contest"

 

[Nycedreemz]

In all honesty I find it hard to believe that in a locking cord that an improper connection can take place due to the fact that they are Locking style and can only fit into themselves. I feel that if a mismatch were to take place it would be the result of the actual wiring of the original receptacle (source) to be wired incorrectly from the start.