'X' receptacles?

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K8MHZ

Senior Member
Location
Michigan. It's a beautiful peninsula, I've looked
Occupation
Electrician
Funny thing is, I have found a few of these receptacles over the years in old houses, most with only 2 prongs, at one time I found a Leviton one and looked it up on their web site from the numbers on the receptacle, there used to be an old thread on it but not sure if it was before the 2003 software change, so at one time they did install them:jawdrop:, more common today is the combo 15 or 20 amp 125/250 volt receptacle that is a duplex with one 250 volt and one 125 volt receptacle, I tried to search Leviton's web site but can not find the old one any more.

P.S. not sure if I ever found a grounding version but I do remember the non-grounding ones.

If you look close, they aren't the same. I have the old ones you are describing right here in my own home.

They (the old 20A 115 volt recepts.) don't have a grounding conductor. Also, the slots are both small, not both large like in the X receptacles. A two prong polarized plug won't fit either way in the old 20A 115 volt receptacles, but will fit both ways in the X receptacle.

I am also not sure if the old 20A 115V recepts. will accept a 240 volt plug like the X receptacles will.

I think this house was built in 1940 or so. It has those receptacles, ashphalt NM in the basement and K&T in the garage. It also as surface mount switches for K&T, those are cool. When I first saw the X receptacles I just thought they were grounded versions of the old 20A 115V's but now I know better.
 
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G._S._Ohm

Senior Member
Location
DC area
Given the power that UL has, I would think they and their employees are under enormous financial pressure from all kinds of wannabees to "sell" their label. But I cannot find a hint of scandal associated with these guys except for the Ryan guy who seems to have questioned their 9-11 involvement.

Please post back on this. Your letter looks just like the ones the "captive agency" I used to work for would send out to the public.

I found an IKEA 13w fluorescent bathroom fixture that asked for 105C wire which UL told me was only for commercial use and they wanted me to investigate this on my own dime.
Dunno' if IKEA still sells this, you had to open the package to find the wire requirement.
 

n1ist

Senior Member
Location
Massachusetts
Occupation
Principal Electrical Engineer
I just pulled a GE one this weekend. It has a UL mark, and is stamped 15a/125v. Probably original in the building from 55 years ago. True to the label, it was fed from a 15A 110v circuit.
 

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K8MHZ

Senior Member
Location
Michigan. It's a beautiful peninsula, I've looked
Occupation
Electrician
I'm not comfortable with cutting and pasting the e-mails I got from UL without their permission, that's why I mostly paraphrased.

Once the UL realized they had a product that violated their trademark I got an e-mail stating that two investigations had begun, they gave me the PIR #s for those investigations and told me that although I would not get details of the investigation, I would be informed of the outcome.

I did get more details than I expected, especially after I sent them a receptacle. Here are some I think I can share.

The receptacle I have has the 'X' configuration along with a UL logo and the UL file number E243553.

Other receptacles purchased by the UL investigators that had the 'X' configuration did not have a UL logo.

Receptacles that are pictured on the internet with the 'X' configuration have the file number on the yoke, but the back of the receptacle is not visible.

So far, the company that makes the controllers I got the receptacles out of is the only one found with the UL mark on the back of an 'X' receptacle.

The UL said they will 'take necessary actions to take the necessary action to address units in the field and correct the manufacture’s process.

Also, the UPS place in Green Bay was just the place I had to send the receptacle. The agent's office is in Northbrook, IL.

While looking for the mfgs. address, I ran across this and may start a separate thread about it. It looks like you plug it into two 120 volt receptacles and get 240 volt power. They also sport an ETL listing and are made by the same company the receptacles I have came from.

orion 1.png
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renosteinke

Senior Member
Location
NE Arkansas
"The agent's office is in Northbrook, IL"

Think about that for a moment. Do you really think the agent drives to Northbrook, from Green Bay, every day?

Or, maybe, does my post about UL having all manner of folks working out of their homes, with periodic visits to the 'home office,' make more sense?

I'll tell you one thing .... I've been to two UL 'home offices,' and neither had the capacity to handle the private aircraft the agents would need to use for such a daily commute.
 

K8MHZ

Senior Member
Location
Michigan. It's a beautiful peninsula, I've looked
Occupation
Electrician
I just pulled a GE one this weekend. It has a UL mark, and is stamped 15a/125v. Probably original in the building from 55 years ago. True to the label, it was fed from a 15A 110v circuit.

I am surpised they are only 15A with the side slot. But, that was many design changes ago. I don't feel like tearing mine out right now, but I do have one on the garage that needs to be removed and added to my collection. I'll be sure to read the fine print before it hits the curio cabinet.
 

K8MHZ

Senior Member
Location
Michigan. It's a beautiful peninsula, I've looked
Occupation
Electrician
"The agent's office is in Northbrook, IL"

Think about that for a moment. Do you really think the agent drives to Northbrook, from Green Bay, every day?

Or, maybe, does my post about UL having all manner of folks working out of their homes, with periodic visits to the 'home office,' make more sense?

I'll tell you one thing .... I've been to two UL 'home offices,' and neither had the capacity to handle the private aircraft the agents would need to use for such a daily commute.

The agent's office is in Northbrook. The UPS box I sent the receptacle to was in Green Bay. One company under scrutiny is in Vancouver, WA, the other in China.

That's all I stated. The area code for the TX he gave me is a Northbrook area code.

I don't really care about, nor do I think the exact location of the agent's residence has any relevance to the thread nor the investigation being discussed. The set up of his office is of no relevance, either.
 

K8MHZ

Senior Member
Location
Michigan. It's a beautiful peninsula, I've looked
Occupation
Electrician
I just found an old ungrounded Homart receptacle with the 'double T' configuration. It's got paint on it and I don't think it will make for a good pic, but it's like the other one already posted here.

It does say 15A 125 volt.

It also says 10A 250 volt and only has two terminals. One is brass and the other is silver color. I think it's circa 1940 - 1950.
 

K8MHZ

Senior Member
Location
Michigan. It's a beautiful peninsula, I've looked
Occupation
Electrician
I also found a very small UL mark on the old Homart receptacle. So, it appears that, at one time at least, UL did approve receptacles that would accept both 120 and 240 volt un polarized, non-grounded plugs. They will not accept polarized 120 volt plugs, which is probably why most of them get pulled and changed.
 

hurk27

Senior Member
After searching a little I found that these receptacles did have a NEMA standard, 1-15/2-15 (T-Slot tandem) and were installed in homes from the 1930's till the early "60's" probably why we are still seeing them, the 2-15 NEMA configuration was removed from the standard in the early 60's as grounding requirements were developed and it was replaced by the 6-15 as we see today, while NEMA 1-15 plugs are still used (mainly on lamps and small appliances) there is no receptacle as the 5-15 replaced it but still accepts the NEMA 1-15 plug as does the NEMA 6-15 accept the 2-15 (Obsolete)

The "X" receptacle you found seems to be a copy of this design by combining the 5-15 with the NEMA 6-15 but is not a NEMA listed or UL listed configuration


Common appliances to use the NEMA 2-15 or 2-20 were old 220 volt kitchen heating kitchen appliances, wall/window A/C units, Well pumps, Space heaters, all having the 220 volt rating instead of the more common today 240 volt rating.

The 110/220 voltage standard was a left over from the carbon filament Edison lamp days, it was most efficient at 100 volts and with the voltage drop of the distribution system back then 110 volts was settled on as the voltage standard.

At work we still have old disconnects labeled as 110/220 volts 25 Hz's.
25hz was Tesla's/Westinghouse old Polly phase standard when he developed the two phase generators.


Most of the above I just found out by searching on the subject but some of it I remembered just can't remember from where:blink:
 
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fmtjfw

Senior Member
I believe that the phone company still uses 25 Hz for ringing land-line telephones.

Most popular ringing current is 20HZ. There was some harmonic ringing with tuned bells for different frequencies, but that was not popular. I think, but am not sure, that the 20HZ mechanical bells ring at that rate.
 

K8MHZ

Senior Member
Location
Michigan. It's a beautiful peninsula, I've looked
Occupation
Electrician
After searching a little I found that these receptacles did have a NEMA standard, 1-15/2-15 (T-Slot tandem) and were installed in homes from the 1930's till the early "60's" probably why we are still seeing them, the 2-15 NEMA configuration was removed from the standard in the early 60's as grounding requirements were developed and it was replaced by the 6-15 as we see today, while NEMA 1-15 plugs are still used (mainly on lamps and small appliances) there is no receptacle as the 5-15 replaced it but still accepts the NEMA 1-15 plug as does the NEMA 6-15 accept the 2-15 (Obsolete)

The "X" receptacle you found seems to be a copy of this design by combining the 5-15 with the NEMA 6-15 but is not a NEMA listed or UL listed configuration


Common appliances to use the NEMA 2-15 or 2-20 were old 220 volt kitchen heating kitchen appliances, wall/window A/C units, Well pumps, Space heaters, all having the 220 volt rating instead of the more common today 240 volt rating.

The 110/220 voltage standard was a left over from the carbon filament Edison lamp days, it was most efficient at 100 volts and with the voltage drop of the distribution system back then 110 volts was settled on as the voltage standard.

At work we still have old disconnects labeled as 110/220 volts 25 Hz's.
25hz was Tesla's/Westinghouse old Polly phase standard when he developed the two phase generators.


Most of the above I just found out by searching on the subject but some of it I remembered just can't remember from where:blink:

Great info, thanks!

Do you happen to know when the NEC put the non-interchangeability rule in the book? 406.3 F in the 2008 book.


Where did you find the old NEMA standards?
 

G._S._Ohm

Senior Member
Location
DC area
While looking for the mfgs. address, I ran across this and may start a separate thread about it. It looks like you plug it into two 120 volt receptacles and get 240 volt power. They also sport an ETL listing and are made by the same company the receptacles I have came from.

orion 1.png
screen shot 2011-09-07 at 2.07.48 pm_596x317.jpg
I can't imagine this gadget being patented.
http://en.wikipedia.org/wiki/Inventive_step_and_non-obviousness

B
ut that's OK; while I was at the USPTO I saw a patent application for a type of paper clip. I would have rejected it.
 
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hurk27

Senior Member
Great info, thanks!

Do you happen to know when the NEC put the non-interchangeability rule in the book? 406.3 F in the 2008 book.


Where did you find the old NEMA standards?



135px-Combo-outlet.jpg 195px-Tslotplug.jpg
Left: extremely old "Nurpolian"-brand black parallel and tandem duplex outlet rated at 250 V 10 A (although normally supplied with 120 V). Right: T-slot duplex outlet.


US Combination duplex outlet
The parallel and tandem outlet accepts normal parallel NEMA 1‐15 plugs and also tandem NEMA 2‐15 plugs. Both pair of receptacles are fed internally by the same supply.

A more recent and fairly common version of this type is the T-slot outlet, in which the locations of the tandem and the parallel slots were combined to create T-shaped slots. This version also accepts normal parallel NEMA 1‐15 plugs and also tandem NEMA 2‐15 plugs. Incidentally, a NEMA 5‐20 (125 V, 20 A), a NEMA 6-15 (250 V, 15 A) or 6‐20 (250 V, 20 A) plug with a missing ground pin would fit this outlet. This type is unavailable in retail shops since the 1960s.

From the bottom of HERE

And here

And a few other places on the net.

As far as when the NEC put the non-interchangeability rule in the book? not sure, but the polarized requirement was around 1948, so any you found like above are from that time or after.
 
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