NEMA 6-20R for 110VAC - is it ok ?

Status
Not open for further replies.
M

mjbanks

Member
Location
Salem New Hampshire
My delima is one that I've been wrestling with for a while with no resolve. I have equipment that uses rectifiers that will operate at an input of 90VAC to 250 VAC. The user has requested 110VAC 20AMP 100% load circuits to be terminated on NEMA 6-20R receptacles. At a later time, the circuits may be upgraded to 220 VAC. Can 110 VAC be applied to a NEMA 6-20R receptacle, and still meet code ? Thanks Mike
 
mjbanks said:
Can 110 VAC be applied to a NEMA 6-20R receptacle, and still meet code ?
Click to expand...
No.
See:
406.7 Noninterchangeability.

6-20r.jpg

NEMA 6-20R receptacle :
20 amp.
250 volt
2-Pole
3-Wire Grounding

(Notice that this configuration is the opposite of 20A/125V but can be confusing when looking at the plug. They are mirror images of each other.)
 
Last edited:
I say no. This violates the listing and intended use of the device. 5-20R devices should be used. If and when the circuit is converted to 240V, only then can the 6-20R devices be utilized.
 
mjbanks said:
At a later time, the circuits may be upgraded to 220 VAC.
Click to expand...

The simple solution is to have the wiring installed to accomadate both/either device type.
When, and IF, the need for change should arise, it is simply a matter of swapping out devices.
 
I disagree ... I say that 406.7 is saying that as long as the receptacle and atachment plug are rated the same then it is ok to use them ... they're both rated for "up to" 250 volts and the configration is the same so should be ok ... M
 
mario said:
I disagree ... I say that 406.7 is saying that as long as the receptacle and atachment plug are rated the same then it is ok to use them ... they're both rated for "up to" 250 volts and the configration is the same so should be ok ... M
Click to expand...
"I don't think so, Tim!" ~ Al Borland from Home Improvement
 
Maybe not NEMA configs, but this says a lot:

406.7 Noninterchangeability. Receptacles, cord connectors, and attachment plugs shall be constructed so that receptacle or cord connectors do not accept an attachment plug with a different voltage or current rating from that for which the device is intended.
 
LarryFine said:
Maybe not NEMA configs, but this says a lot:

406.7 Noninterchangeability. Receptacles, cord connectors, and attachment plugs shall be constructed so that receptacle or cord connectors do not accept an attachment plug with a different voltage or current rating from that for which the device is intended.
Click to expand...

Read that, it is about the construction of plugs and receptacles not the installation of them.

That section does not apply to the OPs question.

However we could still say 110.3(B) but than again is it wrong to use a switch rated 277 volt 20 amps on a 15 amp 120 volt circuit?

Like I said not an easily answered question.
 
Last edited:
LarryFine said:
Maybe not NEMA configs, but this says a lot:

406.7 Noninterchangeability. Receptacles, cord connectors, and attachment plugs shall be constructed so that receptacle or cord connectors do not accept an attachment plug with a different voltage or current rating from that for which the device is intended.
Click to expand...

yo Larry .. this is exactly what I thought I said in my post ... if all are the same configuration and rating as long as the rating is not too low than is ok ... if not , why ... M

Iwire ... I was typing while you were posting ... I believe you said what I meant ... M
 
Last edited:
I can easily imagine someone plugging equipment rated for use on 240v into such a receptacle. I'll concede that this may be a design-issue-vs-code-issue discussion.

What about:

406.3 General Installation Requirements.
(F) Noninterchangeable Types. Receptacles connected to circuits that have different voltages, frequencies, or types of current (ac or dc) on the same premises shall be of such design that the attachment plugs used on these circuits are not interchangeable.

Okay, there may be no 250v receptacles on the premises now, but...
 
LarryFine said:
What about:

406.3 General Installation Requirements.
(F) Noninterchangeable Types. Receptacles connected to circuits that have different voltages, frequencies, or types of current (ac or dc) on the same premises shall be of such design that the attachment plugs used on these circuits are not interchangeable.

Okay, there may be no 250v receptacles on the premises now, but...
Click to expand...

What happens in the future is not an NEC issue.

I can install 600 amps worth of service disconnects protecting 400 amps of service conductors as long as todays calculated load is not more than 400 amps.

What happens tomorrow is up to the next electrician.
 
celtic said:
The simple solution is to have the wiring installed to accomadate both/either device type.
When, and IF, the need for change should arise, it is simply a matter of swapping out devices.
Click to expand...
Just in case clarification is required, the recitifers (furnished with 6-20P) would remain in place for either 110 or 220 VAC. If/when the circuit is upgraded, the NEMA 6-20R stay, the wiring and breaker would be changed. Atleast that was the initial plan. What I'm running into is that my contracted Electricians are going onsite and want to either install the circuit as 220 VAC, or install as 110 VAC / 5-20R. In a couple cases we did have the circuits installed as 110 VAC / 6-20R but they noted the non standard configuration. From the thread, it looks like 406.7 Noninterchangeability details that the same voltage should be used all the way through (breaker to attachment plugs) in this case 240 VAC. I do have the luxury of ordering and changing out the attachment plugs to 15A or 20A, but wanted to try and put this to bed before visiting 20 locations throughout New England and New York... Thanks for your help. Mike
 
About a month ago, I was at a church function...what struck me as "odd" was the twist-lock cap on the microphone - there was a female twist-lock on the wall (to the PA system???) that was it's mate.

I snapped a few pix with my cell-mp3-camera-video-phone:
0606061927em0.jpg

0606061927anc1.jpg
 
celtic said:
About a month ago, I was at a church function...what struck me as "odd" was the twist-lock cap on the microphone - there was a female twist-lock on the wall (to the PA system???) that was it's mate.
Click to expand...

That was the same as the church I went to as a kid and the Jr and Sr high schools I went to,

I have no idea why those where used as you still needed adapters for the mics themselves.
 
celtic said:
About a month ago, I was at a church function...what struck me as "odd" was the twist-lock cap on the microphone - there was a female twist-lock on the wall (to the PA system???) that was it's mate.
Click to expand...

I would think since its at a church function, God will overrule the NEC and any code and make it all safe. Halaluyah PTL
 
What adaptor?
0606061926pt1.jpg


The cap end has only a cap...the mic end may still have it's original cap/connection under that 600v rated tape.
 
The cord removes from the mic via an XLR connector.

Neutrik-NC3FX-B.jpg


Every time we got new mics we had to make twist lock to XLR cords or if we rented mixers we would have to make adapters for the 'other direction'.

The speakers (horns) we used for outdoor events had two wire 15 amp twist locks for the cables.

Yes.....I was in the AV dept. no pocket protector or taped up glasses though. :D
 
Last edited:
Status
Not open for further replies.
Top