workshop wiring

[Andrew Thuswaldner]

Can I have a circuit with 12awg wire that serves two plug outlets, one is a L6-20 (220V@20A) and the other is a 6-15R (220V@15A). The machines plugged into these outlets would never be on at the same time. And could I at some later date change them both to L6-20 outlets?

thanks, Andrew

[John-Paul Murphy]

The key is what is the size of the breaker?
You do not want to have any component in the circuit that is rated lower than the rating of the breaker protecting that circuit. A higher rating is fine but never lower….IMHO:)

[Rod Sheridan]

Hi Andrew, you can indeed have more than outlet on a circuit, however the protection has to be sized for the smallest receptacle.

You can use #12 AWG wire with a 20 ampere breaker and receptacles, however you cannot have a 15 ampere receptacle with a 20 ampere breaker.

Is there a reason you need the 15 ampere receptacle? You could change your cord cap on the 15 ampere unit to a 20 Ampere cap if you wish.

Regards, Rod.

[Chris Friesen]

Can I have a circuit with 12awg wire that serves two plug outlets, one is a L6-20 (220V@20A) and the other is a 6-15R (220V@15A). The machines plugged into these outlets would never be on at the same time. And could I at some later date change them both to L6-20 outlets?

This is perfectly acceptable given that there are two receptacles on the circuit. For a single receptacle on a 20A circuit the code requires a 20A receptacle.

[David Gunn]

This is perfectly acceptable given that there are two receptacles on the circuit. For a single receptacle on a 20A circuit the code requires a 20A receptacle.

I have a question about this. In my garage/shop, the receptacle are run to a 20 amp breaker. The receptacles are all 15 amp though. Are you telling me this is not to code?

[Andrew Thuswaldner]

Thanks for the feedback. The breaker would have to be 20A, I've got that part right. Based on the replies from both Rod and JP, I can see that the issue with what I proposed is the receptacle (6-15) that is only rated for 15A - that is a no-no.
Rod, you asked why I need 15A receptacle? I have a table saw that I re-wired for 220V with a 6-15 plug so that I could use a 14awg run in my house. The saw draws about 6A on 220V. Now that I am re-wiring my garage, adding sub-panel etc. I was looking for way to have some flexibility on some of the new circuits I am putting in. For example, I would like to put a split 110V 20A (5-20R) receptacle on the same run as a 220V 20A (6-20R) receptacle both fed off of a 12 gauge run with a 20A two pole breaker. The 6-15R cord cap on the table saw will (legally) fit into the 6-20R receptacle (I think). The tools won't be running at the same time so I'm not going to be tripping breakers. Let me know if this make sense.
Thanks, Andrew

[Chris Padilla]

I have a question about this. In my garage/shop, the receptacle are run to a 20 amp breaker. The receptacles are all 15 amp though. Are you telling me this is not to code?

The local jurisdiction always has the final say on its interpretation of the code but remember that a breaker protects the wiring IN THE WALL--not what is plugged into it.

#12 protected by 20 Amp breakers is fine.
#14 protected by 15 Amp breakers are fine...#10 by 30 Amp...etc.

You are more than welcome to either match the max current draw (20 A outlets on 20 A circuit) or make it less. Having 15 A receptacles on a 20 A circuit is fine since the load you plan to plug into these outlets will not draw more than 15 A.

In my garage, to save having to buy all sorts of different sized wiring, I just did the entire thing in #10. So all my 20 A circuits are wired with #10.

[Andrew Thuswaldner]

Chris,
Thanks for your input on this thread. Do you have any issues connecting #10 to a 120V 15A receptacle? I mean, is the terminal and screw big enough?
Andrew

[John-Paul Murphy]

IMHO I would not run my shop equipment on 15a outlets since my breakers are 20a ...different states have different codes some counties (parishes etc) even are different so the 15a receptacle may be ok.
Many codes have been updated from 15 amp breakers to 20 amp for outlets as a standard. Though it probably will not be an issue (I make no guarantees) unless you are using hi amp draw tools. I have a 110 air compressor that runs at 18 amps. In that case I would for sure replace the outlets with 20s. not trying to
contradict Chris.. that’s just me. If you are using a local electrical supply house the counter people will usually know what code is for a given location.

[Rod Sheridan]

Hi Andrew, the 5842 receptacle will allow you to have a 240 volt 20 ampere receptacle, and a 20 ampere 120 volt receptacle in one package.

The other way to do it is to use two receptacles in a 4 inch square box, one a 20 A 240V T slot receptacle, and the other a 20A 120V T slot receptacle, both fed from the same 20A 2 P breaker.

This gives you a duplex receptacle with a capacity of 20 A 240V, and two single 120 V receptacles with a capacity of 20 A each. This is a very convenient solution and easy to wire.

For example, connect line A to one line terminal on the 240V receptacle, connect line B to the other line terminal, and connect the groung wire.

Break the paralleling link off of the line terminal of the 120 V receptacle, connect neutral to the neutral terminal, ground to the ground terminal. Now jumper line A from the 240 V receptacle to one line terminal on the 120V receptacle, jumper the other line terminal from the 240V receptacle to the remaining line terminal on the 120V receptacle.

(Obviously the load on line A or Line B cannot exceed 20 Amperes total at any time).


Regards, Rod.

[Jim Solomon]

Hi Andrew, the 5842 receptacle will allow you to have a 240 volt 20 ampere receptacle, and a 20 ampere 120 volt receptacle in one package.

The other way to do it is to use two receptacles in a 4 inch square box, one a 20 A 240V T slot receptacle, and the other a 20A 120V T slot receptacle, both fed from the same 20A 2 P breaker.

This gives you a duplex receptacle with a capacity of 20 A 240V, and two single 120 V receptacles with a capacity of 20 A each. This is a very convenient solution and easy to wire.

For example, connect line A to one line terminal on the 240V receptacle, connect line B to the other line terminal, and connect the groung wire.

Break the paralleling link off of the line terminal of the 120 V receptacle, connect neutral to the neutral terminal, ground to the ground terminal. Now jumper line A from the 240 V receptacle to one line terminal on the 120V receptacle, jumper the other line terminal from the 240V receptacle to the remaining line terminal on the 120V receptacle.

(Obviously the load on line A or Line B cannot exceed 20 Amperes total at any time).


Regards, Rod.
That is what I did at the suggestion of a friend who's a licensed electrician. I am in the process of converting my main panel from 100 amp to 200, as soon as he gets time. Then I will have a dedicated 60 amp box in the shop. As he explained it, it would be more cost effective to run one wire from the main, then to run seperate circuits. My main is 32' from my basement workshop. Not as the bird flies, but for routing purposes.
Jim

[Andrew Thuswaldner]

Rod,
Sounds good. Is there a solution if I want to put locking 220V receptacle in that box with a 110 duplex?
Andrew

[Rod Sheridan]

Yes, just purchase a locking receptacle, although they aren't normally required for a home shop except when mounted on a ceiling........Rod.

[Chris Padilla]

Chris,
Thanks for your input on this thread. Do you have any issues connecting #10 to a 120V 15A receptacle? I mean, is the terminal and screw big enough?
Andrew

I put all 20 A duplex outlets in my garage and the #10 is the max size it can handle and it worked fine. I also used stranded #10...not solid. Solid would have been a nightmare to work with!

Whatever you do, do NOT use back-stabbed receptacles...use back-WIRED receptacles.

[Rick Christopherson]

Hi Andrew, you can indeed have more than outlet on a circuit, however the protection has to be sized for the smallest receptacle.

You can use #12 AWG wire with a 20 ampere breaker and receptacles, however you cannot have a 15 ampere receptacle with a 20 ampere breaker.

Is there a reason you need the 15 ampere receptacle? You could change your cord cap on the 15 ampere unit to a 20 Ampere cap if you wish.

Regards, Rod.Rod, the National Electrical Code permits either 15 or 20 amp outlets on a 20 amp circuit so long as it is not the sole outlet on the circuit (as Chris Friesen already stated). You might be confusing this with 30 amp circuits, where the outlet must be 30-amp without exceptions. The original poster can in fact use his L6-20 and L6-15 outlets on the same circuit.

On a 20 amp circuit, even a single duplex outlet counts as two receptacles, so the other poster that asked about this is fine too.

If I read this thread correctly, Andrew (the OP) also asked about putting 120 volt outlets on this same circuit. This is a permitted use of a "Multi-wire Branch Circuit" so long as you use a 2-pole breaker. (Actually, it is the 240 volt load that causes this requirement.)

[Rick Christopherson]

I have a 110 air compressor that runs at 18 amps. In that case I would for sure replace the outlets with 20s. not trying to contradict Chris.. that’s just me. The electrical outlet is fully capable of providing 20 amps of current without degradation or risk. There is no reason to replace a 15 amp outlet with a 20 amp outlet unless you have power cords that don't fit 15 amp outlets.

[Rod Sheridan]

Rick, thanks for clarification..........regards, Rod.

[Art Travers]

Hi Rod:
Could you clarify for me? I am not up to understanding the nomenclature you are using.
line terminal=hot side
T slot receptacle ? you mention same for both 220 and 120 receptacles..
Thanks ..

[Tom Veatch]

...T slot receptacle ? ...

Look at the slot configuration for the 20 amp receptacles (5-20R and 6-20R) in this diagram (http://www.frentzandsons.com/Hardware%20References/plugandreceptacleconfiguratio.htm#20%20Amp.). One of the slots is sort of like a "tee" so that it can accept either 15 or 20 amp plugs.

[Art Travers]

Thanks Tom,,
I found a 5842 receptacle (hard to find) ..now can somebody tell me how to wire it ?
sorry to be such a knucklehead..

[Rob Russell]

Black/hot conductor to the brass screw.
White/neutral conductor to the silver screw.
Bare/green conductor to the green screw.

Make sure the circuit breaker is off before opening anything up and working on it.

[Art Travers]

Rob:
this is a 220V -125V combo receptacle..
How does this sound ..two hot lines into 220 side ..
jump one the hot lines to the hot side of the 125V
jump the neutral to ground ..Is this correct??

[Tom Veatch]

Rob:
this is a 220V -125V combo receptacle..
How does this sound ..two hot lines into 220 side ..
jump one the hot lines to the hot side of the 125V
jump the neutral to ground ..Is this correct??

You should only have to connect the two hots to the connections on the 220 end, the neutral to the 110 neutral and the ground to the receptacle ground. There should be a jumper already in place between one of the hots to the 110 hot (brass). There should NOT be a jumper between the other hot and the 110 neutral (silver). If the manufacturers jumper is missing, then you'll need to add one of your own. Do not jumper the 110 neutral to ground. Connect the ground to the receptacle ground.
79799

[Jim Becker]

jump the neutral to ground ..Is this correct??

No. You must run a separate neutral from the breaker box to the receptacle. Dual voltage setups are four wire, not three, and ground is not the same as neutral on the 120v side.

[Rob Russell]

Rob:
this is a 220V -125V combo receptacle..
How does this sound ..two hot lines into 220 side ..
jump one the hot lines to the hot side of the 125V
jump the neutral to ground ..Is this correct??

Art - I gave you incorrect information because I didn't go back and reread the entire post (I've been posting in multiple electrical threads recently).

The other guys are correct.

For a 125/250 combo outlet, you will have a total of 4 wires. The NEC calls for both hot legs to be simultaneously disconnected, so this needs to be fed by a 2-pole, 250v breaker - not (2) individual 125v breakers.

(2) hots to the (2) brass screws on opposite sides of the outlet.
(1) neutral to the silver screw. Be careful that the hot and neutral on that side are insulated right up to the receptacle. In other words, don't strip too much insulation off of the conductors.
(1) equipment grounding conductor to the green screw.

Rob

[Russ Filtz]

So to reiterate, a 15A outlet on a 20A breaker is OK by code? I always thought the breaker was supposed to protect the entire circuit, not vice versa. I guess as long as the wiring itself is sized OK, you can use the outlet as a fusible link!

[Tom Veatch]

So to reiterate, a 15A outlet on a 20A breaker is OK by code? I always thought the breaker was supposed to protect the entire circuit, not vice versa. I guess as long as the wiring itself is sized OK, you can use the outlet as a fusible link!

An exception in the NEC permits 15A outlets on a 20A circuit IF and ONLY IF there are two or more in the circuit. Since the "normal" duplex receptacle is considered to be two outlets, the NEC is happy with 15A duplex receptacles protected with a 20A breaker.

[Art Travers]

OK, I see my problem ..only have 3 wires on the circuit..2 hots and ground..
However. see my argument: A single pole circuit has both the neutral and ground
connected to the ground bus in the main breaker box. So what is the difference if
I jump the neutral to the ground in the receptacle? Apparently it is connected
similarly.. Never was good in electrical engineering classes..

[Rob Russell]

OK, I see my problem ..only have 3 wires on the circuit..2 hots and ground..However. see my argument: A single pole circuit has both the neutral and ground connected to the ground bus in the main breaker box. So what is the difference if I jump the neutral to the ground in the receptacle? Apparently it is connected similarly.. Never was good in electrical engineering classes..

To do what you want to do, you MUST have (4) wires
- (2) hots
- (1) neutral
- (1) equipment grounding conductor.

OK - I lied - you don't need the EGC, but I wouldn't run the circuit without it. The neutral must be an insulated conductor. You can't use NM cable (aka "Romex") and use the bare copper wire as your neutral.

You CAN NOT "jump" the neutral to the EGC at the receptacle.

Rob