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cypherstream
Premium,MVM
join:2004-12-02
Reading, PA
kudos:3

Wiring L6-30 208v outlet in place of L5-30 120v

I have a L5-30 outlet that I am measuring 120V on. I need 208V L6-30 outlet for an UPS to plug in for some computer equipment.

The breaker is a double position 30A breaker. Behind the outlet cover is 5 wires, 3 hooked up, two not. The ones hooked up are black, white with green electrical tape wrapped on it and then a green wire.

The wires not hooked up are a red wire (not stripped), and a blue wire which happens to have a wire nut on it and electrical taped really well.

In order to convert this to L6-30 outlet, which wires do I hook up? I'm thinking red, black and white (green tape). Why because the outlet next to it is an L6-20 and thats the only wires connected to it, but thats a 20A breaker and a smaller diameter socket so my UPS power cord doesn't work in that.

Also all the wires look to be 10 gauge. They are THICK. I pulled one out actually and can't get it back in at all. I have NO IDEA how they got the wire in (its like putting a square peg in a round hole). Hopefully if I get a L6-30 receptacle, they make it easier to make these connections. These wires are STIFF.


SparkChaser
Premium
join:2000-06-06
Downingtown, PA
kudos:4
I have to ask. You do have 208V available at the panel? Is this a commercial location?


cypherstream
Premium,MVM
join:2004-12-02
Reading, PA
kudos:3
Yes we do, yes commercial location.


cypherstream
Premium,MVM
join:2004-12-02
Reading, PA
kudos:3
reply to SparkChaser
If I were to guess, I would think Green, Black and Red would be hooked up but what the hell is the blue wire doing in there, and why is it uber protected with a wirenut and layers upon layers of black electrical tape?


John Galt
Forward, March
Premium
join:2004-09-30
Happy Camp
kudos:8
reply to cypherstream
Go to the panel and see what the blue wire is doing...


leibold
Premium,MVM
join:2002-07-09
Sunnyvale, CA
kudos:10
Reviews:
·SONIC.NET

1 edit
reply to cypherstream
I don't like the green tape on the white wire. It appears the neutral wire was re purposed as ground wire but why do that if you have a green ground wire already ? Definitely check how those wires are terminated on the other end and do not rely just on colors.

Common 3 phase color schemas in the US are: Black/Red/Blue (120/208) and Brown/Orange/Yellow (277/480) for Line1/Line2/Line3. White or Gray as Neutral and Green as Ground. The colors for phase wires are not mandated by the NEC but may be specified in local amendments.

Edit: A 2-pole breaker in a 3-phase panel may provide Line1+Line2, Line2+Line3 or Line3+Line1. The fact that there is a capped and taped wire in the outlet box strongly suggests that this outlet has been changed at least once before and there is really no substitute to verifying exactly what changes may have been made. Based on the wire colors that location was originally intended for a 3-phase outlet.
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LazMan
Premium
join:2003-03-26
canada

3 recommendations

reply to cypherstream
Based on your questions... Get an electrician.

Without knowing what's going on at the panel end; impossible to say what to hook up to what...


John Galt
Forward, March
Premium
join:2004-09-30
Happy Camp
kudos:8

2 recommendations

reply to cypherstream
A lot of times Sparky will pull a "round-robin" or "full boat" meaning a full set of colors as leibold See Profile indicated above. This is because it might be a lab or similar where the circumstances and usage change, and it is are "real problem" to go back and add the wire in the future. Since Sparky has all the wire set up and ready to go, they just pull the full boat, cap off what is not used and be done with it.

Ideally, you'd follow the conduit back to the panel so you fully understand what the conductors are doing between the recp and the panel before you do anything. Making assumptions can be...problematic.

InvalidError

join:2008-02-03
kudos:5
reply to cypherstream
Five wires... sounds like that outlet was a Y-topology 3x120V phase-neutral (208V phase-phase) with neutral and ground wires at some point in time.

I'm guessing what you want here is to restore it to its former 3-phase form. You will need to stick a 3-phase breaker in that service panel in place of the current 2-phase one and re-wire accordingly.


leibold
Premium,MVM
join:2002-07-09
Sunnyvale, CA
kudos:10
Reviews:
·SONIC.NET
No, the OP clearly stated that he wants a 208V 30A outlet. The L6-30 is a single phase outlet. Two lines and a ground is all he needs (no neutral).
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lutful
... of ideas
Premium
join:2005-06-16
Ottawa, ON
kudos:1
reply to cypherstream
If you were getting 120V at the outlet, maybe black is connected to one phase and green/white is being used for neutral? Blue may be already connected to another phase at the double breaker.

You have to check that carefully and disconnect the green/white from neutral.

Now you could bring in all 3 phases (L1, L2, L3) over the Red, Blue and Black wires to make 2 separate outlets using L1/L2 and L2/L3 pairs.

Use the solid green wire for grounding one outlet and the green/white wire for grounding the other outlet.



John Galt
Forward, March
Premium
join:2004-09-30
Happy Camp
kudos:8
reply to cypherstream
Reiterating...

Ideally, you'd follow the conduit back to the panel so you fully understand what the conductors are doing between the recp and the panel before you do anything. Making assumptions can be...problematic.

If you can't do this, consult a professional.
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cypherstream
Premium,MVM
join:2004-12-02
Reading, PA
kudos:3
I could pull the cover off the panel to look at the breaker I guess. The outlet next to this one IS 208v, but it's 20A so the plug is different. If I would use that as a guide, it would be Red, Black and Green. However I guess you should never assume and better safe than sorry.


leibold
Premium,MVM
join:2002-07-09
Sunnyvale, CA
kudos:10
Reviews:
·SONIC.NET

2 recommendations

Even if you could depend on the wire colors:
Every 208V circuit in the building will have a different pair of phases depending on where in the panel the two pole breaker is installed. Besides Black-Red and Blue-Black there will also be some that are Red-Blue. Using the same two phases for all 208V circuits would create an unbalanced load. Some electric utilities penalize commercial customers for that (which is a good incentive to do it right).

However the important thing is: YOU CAN'T RELY ON THE WIRE COLORS !.

Are you able to follow the conduit from the outlet back to the electric panel ? You may want to make sure that nobody tapped into the "spare" wires somewhere along the way and used them for another circuit elsewhere.
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LittleBill

join:2013-05-24
kudos:1
reply to cypherstream
l6 p30 is a 208/240 connector, simply tie the neutral wire to the double gang breaker


John Galt
Forward, March
Premium
join:2004-09-30
Happy Camp
kudos:8
said by LittleBill:

l6 p30 is a 208/240 connector, simply tie the neutral wire to the double gang breaker

No....

LittleBill

join:2013-05-24
kudos:1
considering i use these every single day at work. im gonna go with yes


John Galt
Forward, March
Premium
join:2004-09-30
Happy Camp
kudos:8

1 recommendation

said by LittleBill:

considering i use these every single day at work. im gonna go with yes

Why do you think that buildings turn into shit? It's because people do exactly what you are suggesting.


leibold
Premium,MVM
join:2002-07-09
Sunnyvale, CA
kudos:10
Reviews:
·SONIC.NET
reply to LittleBill
I can't believe you are seriously suggesting to attach the neutral to the breaker. The "neutral" in this case is a white wire with green tape which indicates it has been previously used as ground wire.
Attaching this wire to the breaker may result in a dead short or it may electrify some contact surfaces that should be grounded but will now be hot (shock hazard).

Without properly understanding what all is connected to that wire I wouldn't dare using that wire for any purpose.

However your comments are useful because there are other people who actually do what you are proposing for cypherstream See Profile to do. This is the exact reason why verifying the actual wiring is so important and why it is not possible to make assumptions or simply rely on wire colors.
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joel321

join:2013-04-13
USA
reply to cypherstream
Here in the USA 30-45 amp breakers are for HVAC units and stoves. 30Amps for computer equipment...man... to play it safe, we just run a dedicated plug for such amp hungry units....it should take just a few hours...like so...I have never heard here that plugs carry both 120 and 240 in the same line.

Get a 30 amp breaker that complies with your power supply box...there should be extra slots to place it on the 208 line...run the rated wire to your room...done...all in a matter of 2-3 hours.

Easiest way to do it is to pay an electrician to run you a dedicated line...you can do it yourself easy...like i said, but money well spent as long as you don't get over charged.

JoelC707
Premium
join:2002-07-09
Lanett, AL
kudos:5
said by joel321:

Here in the USA 30-45 amp breakers are for HVAC units and stoves. 30Amps for computer equipment...man...

30 amp circuits are quite common for computer equipment, both the 120V and 208/240V flavors. Larger UPS units need them, and still larger units need to be hardwired and skip the outlet altogether (still have a breaker of course, they just get tied into a junction box directly).

said by joel321:

I have never heard here that plugs carry both 120 and 240 in the same line.

Actually, every 240V outlet has 120V available to it. In the USA (and other countries), you get 240V by using both 120V legs so there's actually TWO independent 120V circuits available at every 240V outlet. The only catch is you might not be able to properly use those 120V legs off a 240V outlet. That's because not all 240V equipment requires the neutral, just a ground. Technically you could use the ground as a neutral and get 120V just fine out of it but now you are putting current over a line that isn't supposed to have any except in an emergency. Newer 240V circuits are 4-wire: 2x 120V, 1x neutral and 1x ground. Either one of the hots to the neutral plus ground gets you 120V and is functionally the same as a Multi-wire Branch Circuit (MWBC).

said by joel321:

Get a 30 amp breaker that complies with your power supply box...there should be extra slots to place it on the 208 line...run the rated wire to your room...done...all in a matter of 2-3 hours.

Easiest way to do it is to pay an electrician to run you a dedicated line...you can do it yourself easy...like i said, but money well spent as long as you don't get over charged.

Proper wire and breaker is already there. He indicated a 2-pole breaker was present in the panel that his current 120V circuit is connected to. All he needs to do is identify which two of the three phases the breaker is on and use the appropriate color wires that are already present at the panel and outlet box. An electrician might still be needed if he isn't comfortable working in the panel or seeing what phases to use but he won't need to get another breaker or run any new lines (unless the existing lines have mysteriously been re-purposed along the way).


leibold
Premium,MVM
join:2002-07-09
Sunnyvale, CA
kudos:10
Reviews:
·SONIC.NET
reply to joel321
The L21 connector is a 3 phase 5 wire outlet with ground and neutral. This provides a maximum of flexibility to attach different kinds of loads. It supports both delta and wye connected 3 phase loads or alternatively three 120V and 208V single phase loads (shared neutral in the case 120V loads).

The L14 is another (more common) 4 wire connector with 2 lines neutral and ground for single phase 120V + 208/240V applications.
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LittleBill

join:2013-05-24
kudos:1
reply to leibold

Re: Wiring L6-30 208v outlet in place of L5-30 120v

said by leibold:

I can't believe you are seriously suggesting to attach the neutral to the breaker. The "neutral" in this case is a white wire with green tape which indicates it has been previously used as ground wire.
Attaching this wire to the breaker may result in a dead short or it may electrify some contact surfaces that should be grounded but will now be hot (shock hazard).

Without properly understanding what all is connected to that wire I wouldn't dare using that wire for any purpose.

However your comments are useful because there are other people who actually do what you are proposing for cypherstream See Profile to do. This is the exact reason why verifying the actual wiring is so important and why it is not possible to make assumptions or simply rely on wire colors.

I simply indicated that moving the Neutral wire to L2 would work, who in their right mind would only fix ONE SIDE of the wiring?

i thought it was obvious that all wire would be checked. considering about 18 people in here indicated the same.

i simply indicated that the connector can be used both for 208/240, not just 208. and the wiring reused.

i did not realize i needed to write the post for 7 year olds to follow, since i figured 7 year olds will not be touching this.

maybe i should start my posts with "if your an idiot stop reading now"

JoelC707
Premium
join:2002-07-09
Lanett, AL
kudos:5

1 recommendation

You don't need to use the neutral at all in this case. I can't speak for the others but I suspect that's what they are getting at. The OP indicated that all 5 wire colors are available in the outlet box. There's no need to re-purpose the neutral when the correct wire colors are there and ready for use.

The only thing that needs to be done is to follow the conduit and check all junction boxes to make sure the wires go back to the panel and aren't "tapped into" by way of a lazy person not wanting to pull the correct wires out of the panel. Then you need to see which of the two phases the existing 2-pole breaker is on so you know which two wire colors to use (electricity is color blind so it won't care, but the next person that comes along to work on this might like to know which phases this outlet is on so using the correct color wires helps).

LittleBill

join:2013-05-24
kudos:1
"if your an idiot stop reading now" -Disclaimer

agreed the neutral is not required, i was initally just skimming the post and was pointing out the connector was also rated for 240v

that said we use THHN everywhere, so it all gets color coded regardless.

that being said if the wires are capped or strip, there is a possibility the unused wires are simply cut and not long enough to reach back at the breaker box. i have seen this on occasion as well


LazMan
Premium
join:2003-03-26
canada
reply to JoelC707
I use plug and socket connections for 50A and 60A 240v all the time; for computer equipment... It's not at all uncommon.

There's some horrible advise being given in this thread; both bad practices and outright dangerous...

OP - I stand by my initial statement - get a qualified, licensed electrician in...

JoelC707
Premium
join:2002-07-09
Lanett, AL
kudos:5
Oh yeah, there's no reason you can't put a 6-50 or similar on a high capacity UPS that expects to be hard-wired. Beyond about 50A though, unless you go to a pin and sleeve connector, you are likely stuck hard wiring it (and given the likely cost of those compared to a junction box and wire nuts, it makes sense why most default to hard wired).


cypherstream
Premium,MVM
join:2004-12-02
Reading, PA
kudos:3
reply to cypherstream
Ok I had time to check the breaker panel. So what I found this double breaker which is on the left side about halfway down had only black connected to the top left terminal of it. I saw the blue wire, capped and electrical taped and connected to nothing. So I take it I can attach that blue wire to the bottom left terminal of this breaker and then at the outlet take the cap off the blue wire there and wire that to the outlet?

The wires are home runned in armored cable.

So the new outlet has G, X, Y. Should it be solid green for G, blue for X and black for Y?

JoelC707
Premium
join:2002-07-09
Lanett, AL
kudos:5
You should verify which phase is set for blue but given it's been capped and taped in both locations I'd say it was the one previously used there and should be safe to simply connect it and use it. Normally I always do black as X, technically though, electricity and other devices are color blind and won't care one way or the other.