ECN Electrical Forum - Discussion Forums for Electricians, Inspectors and Related Professionals
ECN Shout Chat
Recent Posts
Grounding electrodes
by gfretwell - 09/07/21 03:41 PM
Looking For Electricians in the Midlands
by Alex247 - 09/06/21 05:26 AM
Backup Generator Done Right
by timmp - 08/31/21 04:44 PM
New in the Gallery:
Now you know.
Now you know.
by Tom_Horne, September 7
February, North East Indiana
February, North East Indiana
by timmp, July 25
Who's Online Now
0 members (), 39 guests, and 19 robots.
Key: Admin, Global Mod, Mod
Previous Thread
Next Thread
Print Thread
Rate Thread
Page 1 of 3 1 2 3
Joined: Apr 2007
Posts: 37
Moderators, if you could move this to the electrical nostalgia section...Thanks.

I was rummaging through some old devices that I had lying around the other day and came across this older Hubbell Twistlock Receptacle. I've seen many of these installed in older buildings, and I'm assuming that this one predates the nema standard for locking devices. A modern NEMA L5-15 R has a little hook in on the ground slot so this one looked a little odd to me. It carries a dual voltage rating as well. (these are a little before my time)

[Linked Image from]
I got also a bunch of these single Hubbell (and some A-H)receptacles that have a really odd mount. They were in a box of really old electrical stuff at a garage sale. At first you would think that this could fit a raised cover with an opening for a single receptacle, however, the mounting tabs are about a 1/4" too small. I have no idea what these could have been used for, maybe some older plugmold type strip or something. (I have an "adjustment yoke" for a blank cover lying next to it for a gauge)

[Linked Image from]

[Linked Image from]

Joined: Sep 2002
Posts: 910
Likes: 1
If you were to take a locking type photocell & compare the configuration of it and the one in the top picture, they are the same, & the receptacle in 2nd pic. is a floorbox receptacle.

Joined: Mar 2004
Posts: 251
I have a box of those Twist loc rec. It is a non grounding type. They were common used during the late 1950 & 60's on fire apparatus. Used on fans & lights. They made a 2 conductor also. They were frequently miss wired as the screws on the early models were not identified. I was in a fire dept that used these. Several of the lights were mis-wired. When you started the generator on the pumper and stretched the cord to a light set on the (wet) ground, if you touched the truck, you got a tingle. One pole was grounded in the generator and the other on the light. Replaced them all with grounded and properly wired TL.

Joined: Jul 2001
Posts: 599
JBD Offline
"Old style" (non-grounding) twist lock devices are still available from most manufacturers.

Joined: Nov 2008
Posts: 1
New Member

Re the first picture—up to the early 1970s in northern California, these were used extensively on construction sites. At temporary power poles, typically there were a pair of these, one receptacle was labeled “110” and the other was labeled “220”. That way extension cords could be used for either voltage. (Never mind the hazards.)

This was at a time when CALOSHA was just comin’ up to steam, and inspectors were busy with site inspections and issuning citations.

Joined: Jul 2002
Posts: 8,407
Likes: 2
Good stuff,
Junk collector.
I fail to see however, how this is junk.

One thing I love about the older sockets and the like is the small designs used to adorn something like a receptacle.
Like the front face of the recept in your second picture, someone designed that, who I have no idea, but at the time that would have looked good.

To most people that is somewhere where you put your plug in to get something to work.

It's a shame that only electricians appreciate the work that went into these devices. frown

Joined: Nov 2002
Posts: 790
[Linked Image from]
Here's an old outlet in my mom's place. Turns out Australian plugs will fit, and as this one is fed by 240VAC, the Australian plug would feel nearly at home. Except for the 60Hz, and that both current carrying pins (that's the slanted ones, the vertical one is the ground) are hot with 120VAC. In Australia, one is a neutral, and the hot is 240V 50Hz.

Joined: Apr 2007
Posts: 37
That is a neat receptacle, Wa2ise. I've seen a few of those, but they were wired for 120. A hardware store near me still has the single version of that style, and the NEMA 10-20. I think they have plugs for each variety, too. I actually have an adaptor with that crowfoot pattern, so that you can plug the crowfoot into a standard receptacle.

Good stuff...

Joined: Feb 2002
Posts: 183
Back in my elementary school, we had crowsfoot for 110DC and regular for AC (or was it the other way around? Too long ago :-)

Joined: May 2005
Posts: 984
All our 120V stuff at Ford was fitted with a weird twist-lock pin-and-sleeve plug that fitted into matching weird receptacles.
I know that whacking off the plug of a new tool to install an oddball plug sounded dumb, but we stopped 'losing' electric drills and other small power hand tools almost immediately after the policy was adopted.

Page 1 of 3 1 2 3

Link Copied to Clipboard

Tools for Electricians
Tools for Electricians

* * * * * * *

2020 Master Electrician Exam Preparation Combos
2020 NEC Electrician
Exam Prep Combos:
Master / Journeyman


Member Spotlight
Fullerton, CA USA
Posts: 4,287
Joined: December 2000
Top Posters(30 Days)
timmp 3
Popular Topics(Views)
282,928 Are you busy
216,696 Re: Forum
203,120 Need opinion
Powered by UBB.threads™ PHP Forum Software 7.7.5