Adapting 14-30R to 6-20R?

[Justintime2]

I’ve got a washer/dryer plumbed/wired in my shop and will likely never use it. I’d like to get a plug-n-play adapter pigtail to convert the dryers NEMA 14-30R plug to a NEMA 6-20R for a Cadet RCP-402S heater. Only adapters I keep finding however are for a 14-30P.

Can I do what I’m trying to do and does the P vs R matter? Help!

 

[sberry]

If you never use it why fug with the adapter? But,, the reason you can't find one it's not code compliant, if it came factory 20 end then it needs a current limited circuit at 20A. Cant have a 30 breaker on 20 outlet. Change the outlet,, change the breaker.

 

[sberry]

P is for plug,, R is for recept.

 

[Lightning rod]

Better to change out breaker and receptacle but if you really still want to get the appropriate
Plugs and sockets, McMaster-Car has them

https://www.mcmaster.com/nema-6-20-connectors/type~socket/

 

[Justintime2]

Fair point to just change the breaker and receptacle, wanted to avoid it if possible but frankly that’s safer and I can always switch it back.

What would the wiring look like though going from 4 wire 220 dryer plug receptacle to a 3 wire 220 one?

I understand 110 better...

 

[Justintime2]

P is for plug,, R is for recept.

Face palm after realizing it was that simple. I’m a DC guy so my AC understanding is more limited.

 

[Bert_]

14-30P is the plug that fits a 14-30R receptacle.

 

[yatg]

No neutral connection in the 6-20R. Just hot,hot,ground.

 

[Justintime2]

14-30P is the plug that fits a 14-30R receptacle.

Ya I feel pretty dumb after that one...

 

[Justintime2]

So this adapter would work it’s just not recommended for the reasons discussed above?

 

[wyliesdiesels]

unless the heater has integral overload protection, you will need to change the breaker to 20a

 

[Justintime2]

unless the heater has integral overload protection, you will need to change the breaker to 20a

Only thermal overload protection. So if I wanted to leave the outlet alone, use this adapter then just swap out the breaker to a 20a would that be safe?

 

[sberry]

With a breaker change it would be safe. I am not sure how they sell that adapter,,,, we'll I guess you could sell it but doesn't make it legal.

 

[sberry]

I bet it has thermal but normally stuff comes with a plug is very specific about the overcurrent, it may rely on the breaker for short circuit. At 4k watt and heavy cord it could be fine at 30,,, maybe not, but you got to spend 30 on an adapter to do it wrong.

 

[sberry]

I write notes on the cover if you change it, 10-4 wire etc, not required to but let's someone know it could be changed back.

 

[Justintime2]

Thanks for all the comments guys. Learned something new and now have a few options to do this, appreciate it!

 

[sberry]

The correct option is a recept and a breaker.

 

[Justintime2]

Agreed but am prob going to go adapter cord and breaker route. This heater will only be in use while I’m in their working and not on while gone. This allows me to plug it at my other place as well.

 

[The Cobbler]

not sure why you insist on not changing the receptacle while you're at it

 

[Justintime2]

You guys are persistent, maybe I’ll just do the receptacle and breaker. So if I change the receptacle to a 6-20R then the two hots and ground get used and the neutral capped off?

 

[wyliesdiesels]

Agreed but am prob going to go adapter cord and breaker route. This heater will only be in use while I’m in their working and not on while gone. This allows me to plug it at my other place as well.

well changing the breaker and not the outlet would be a code violation since the 30a outlet needs to be on a 30a breaker

You guys are persistent, maybe I’ll just do the receptacle and breaker. So if I change the receptacle to a 6-20R then the two hots and ground get used and the neutral capped off?

correct. neutral not needed

 

[Justintime2]

You guys win, I’ll ditch the adapter idea. Breaker and receptacle change inbound!
Tough crowd in here but it’s what I needed...

 

[Norcal]

You guys win, I’ll ditch the adapter idea. Breaker and receptacle change inbound!
Tough crowd in here but it’s what I needed...

Best to do it right. Most if not all of those adapters are not even listed by UL or other recognized testing lab.

 

[wyliesdiesels]

You guys win, I’ll ditch the adapter idea. Breaker and receptacle change inbound!
Tough crowd in here but it’s what I needed...

tough crowd cause we follow code and want to make sure things are done safely?

 

[Justintime2]

Just a little bit of humor...doesn't even approach tough.
Thanks for the info!

 

[u2slow]

You guys win, I’ll ditch the adapter idea. Breaker and receptacle change inbound!
Tough crowd in here but it’s what I needed...

I'm compelled to point out... a group of baseboard heaters (say 5x 1000W) can each be fed with a #14 wire, yet share a #10 home-run off a 30A breaker. Overcurrent protection is clearly not the paramount concern for resistive heat.

 

[sberry]

That's because they are not using the breaker for thermal, that is done by calculated load. But,,, the wires have to be adequate to support short circuit interruption. for a 30 its 14. Got to limit 16 to 20
I eluded to this in another thread with comp feeds, they used taps on main fuses at 60, used a 10 to a bandit with 30 in it for 3 hp comps back in the day when 60A fuses were the norm.

 

[sberry]

This is why there would be concern with running that on 30 despite having adequate cord and thermal,,, a guy would have to look internal to the unit to see if all the parts, control or fan wires mainly were rated 30A,,, I suspect since it comes 20 end fan is 16 wired.
On some units where there are 120 models and 240 they share some same parts but oft change some control wire, fan or ****** leads to 14 for the 240/30Amodels so they don't need to add another layer of internal protection.
Same for air comps, guy starts adding **** to them not designed for 30_50A service.

 

[Justintime2]

Thanks for all your help and tipping me in the right direction!

 

[nadogail]

Very informative comments.

 

[AntonLargiader]

That metal cabinet edge, looking like it's trying to pry its way between the plug and the recep, gives me the willies. What are the odds that things were going to line up that way...

 

[Justintime2]

Pic is a little deceiving. The tool box lip is actually higher then the plug itself and is sitting forward of it but the angle doesn’t reflect that. No chance it’s getting in there!