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#187981 - 07/15/09 08:17 PM Older twistlock and other odd receptacle
junkcollector Offline

Registered: 04/15/07
Posts: 35
Loc: Central MN
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)

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)

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#187985 - 07/15/09 09:37 PM Re: Older twistlock and other odd receptacle [Re: junkcollector]
NORCAL Offline

Registered: 09/25/02
Posts: 805
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.

#188039 - 07/17/09 09:20 PM Re: Older twistlock and other odd receptacle [Re: NORCAL]

Registered: 03/29/04
Posts: 252
Loc: Kingwood, TX USA
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.

#188053 - 07/19/09 07:30 PM Re: Older twistlock and other odd receptacle [Re: WESTUPLACE]
JBD Offline

Registered: 07/12/01
Posts: 599
Loc: WI, USA
"Old style" (non-grounding) twist lock devices are still available from most manufacturers.

#188423 - 08/07/09 06:31 PM Re: Older twistlock and other odd receptacle [Re: JBD]
busbar Offline
New Member

Registered: 11/21/08
Posts: 1
Loc: Way Out West

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.

#188429 - 08/08/09 01:38 AM Re: Older twistlock and other odd receptacle [Re: junkcollector]
Trumpy Offline


Registered: 07/05/02
Posts: 8532
Loc: SI,New Zealand
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
Let's face it, these days if you're not young, you're old - Red Green grin

#189807 - 10/26/09 12:16 AM Re: Older twistlock and other odd receptacle [Re: Trumpy]
wa2ise Offline

Registered: 11/29/02
Posts: 769
Loc: Oradell NJ USA

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.

#189828 - 10/26/09 06:47 PM Re: Older twistlock and other odd receptacle [Re: wa2ise]
junkcollector Offline

Registered: 04/15/07
Posts: 35
Loc: Central MN
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...

#189857 - 10/28/09 06:07 AM Re: Older twistlock and other odd receptacle [Re: junkcollector]
n1ist Offline

Registered: 02/13/02
Posts: 176
Loc: Malden MA
Back in my elementary school, we had crowsfoot for 110DC and regular for AC (or was it the other way around? Too long ago :-)

#189871 - 10/28/09 12:34 PM Re: Older twistlock and other odd receptacle [Re: n1ist]
ghost307 Offline

Registered: 05/09/05
Posts: 883
Loc: Chicago Illinois USA
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.

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