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Polarized Extension Cord Feeding Non-Polarized LED Supply Cord

11/26/2017 8:12 PM

This year I bought new Christmas yard decorations with LED lights. They come with ungrounded, unpolarized, hermaphrodite/gang/multiple plugs.

I don't own any non-polarized extension cords.

Why aren't the plugs polarized? Grounded?

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#1

Re: Polarized Extension Cord Feeding Non-Polarized LED Supply Cord

11/26/2017 8:44 PM

Providing them as polorized would give the impression that it's necessary when it's not.

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#2
In reply to #1

Re: Polarized Extension Cord Feeding Non-Polarized LED Supply Cord

11/26/2017 9:31 PM

But, it would also allow them to be used without any bother in 99.9% of applications where polarization is common.

At no additional cost.

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#6
In reply to #2

Re: Polarized Extension Cord Feeding Non-Polarized LED Supply Cord

11/27/2017 7:28 AM

?? The ones I have CAN be used in any outlet. Both blades of the plug are the smaller style without the flared end, so they fit into any receptacle. They're the most 'universal' of any type of plug in the US.

Were you planning to take your Christmas lights across the pond?

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#8
In reply to #6

Re: Polarized Extension Cord Feeding Non-Polarized LED Supply Cord

11/27/2017 12:56 PM

Let me try again. All my extension cords are polarized, as in the picture. Most are also 3 prong, grounded, but the one I connected the strings of lights is a cheapy six footer specifically for this purpose. (still polarized)

My Christmas lights have plugs like the NEMA 1-15P, non-polarized, as on the right below.

So, in order to use a polarized extension cord, I had to cut the polarizing lug down to fit.

Why didn't the Christmas light cord designers make one of the female slots wider, as depicted in the NEMA 1-15P, polarized plug. No other changes would have been necessary to render the non-polarized plugs compatible with polarized male plugs.

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#9
In reply to #8

Re: Polarized Extension Cord Feeding Non-Polarized LED Supply Cord

11/27/2017 1:05 PM

Ah, so it's unpolarized sockets that are the problem...

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#12
In reply to #9

Re: Polarized Extension Cord Feeding Non-Polarized LED Supply Cord

11/27/2017 5:32 PM

Yeah... The OP always manages to leave out a crucial bit of information. If Lyn were replying to OP, he'd rip him a new one because of it.

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#13
In reply to #12

Re: Polarized Extension Cord Feeding Non-Polarized LED Supply Cord

11/27/2017 5:44 PM

Oh, sure. Jump all over me for not sexing the end of the ungrounded, unpolarized, hermaphrodite/gang/multiple plugs that I was having problems with.

I assumed that you all would know that when I said "problems" it would be obvious that the female (socket) would be the cause of my consternation.

That's my story and I'm sticking to it!

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#14
In reply to #13

Re: Polarized Extension Cord Feeding Non-Polarized LED Supply Cord

11/27/2017 8:11 PM

You could get out your file and file down the neutral pin on your extension cord.

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#15
In reply to #14

Re: Polarized Extension Cord Feeding Non-Polarized LED Supply Cord

11/27/2017 8:20 PM

Diagonal cutters took care of things.

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#36
In reply to #13

Re: Polarized Extension Cord Feeding Non-Polarized LED Supply Cord

11/29/2017 3:47 PM

I can see you're having problems with all sorts of things, but strictly speaking a hermaphrodite connector would have at least one pin and at least one socket. Did you know that most snails are hermaphrodites? If you talk about male and female connectors, be careful not to include Germans in your audience, for they will just snigger (I speak from experience).

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#38
In reply to #36

Re: Polarized Extension Cord Feeding Non-Polarized LED Supply Cord

11/29/2017 4:51 PM

Until today I had not consumed tequila for a considerable period of time.

After experiencing the agony of this thread, and especially this one Continuously Connected - How Is It Done?, I have broken that prohibition in utter frustration and disbelief that I don't seem to be able to convey even rudimentary thoughts and concepts to others.

Here is yet another photo of the plug that is the cause of my grief.

I believe that it is clearly an ungrounded, unpolarized, hermaphrodite/gang/multiple plug item.

There is only one of these ungrounded, unpolarized, hermaphrodite/gang/multiple

plugs per string of lights so that an extension cord is required to connect multiple

strings for the desired effect, shown here.

Merry Christmas to all, and to all a good night.

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#39
In reply to #38

Re: Polarized Extension Cord Feeding Non-Polarized LED Supply Cord

11/29/2017 6:37 PM

Slowly, we're getting somewhere...

From your post #20, I had the impression that the multi-outlet adapter

was the problem.

Now it appears that that adapter was not the problem, and totally unnecessary as well. If you had plugged the white hermaphrodite connector directly into the orange standard 3-wire extension cord, then you could have plugged your (modified) 2-wire extension cord directly into the female side of that white connector.

Now, to answer your (I think original) question: "...why not make one slot of of the female, non-polarized socket wider to accommodate a polarized plug?".

Doing so would give the impression that that female connector is polarized, when in fact it is NOT.

If you were to widen one of the slots on the female side of the white connector (or on any other non-polarized device having a female outlet) then a polarized device could be plugged in to that outlet. In your particular case there is no need for polarization, since (I presume) all the devices powered by that second extension cord are non-polarized devices.

But think for a moment about a standard metal-cased toaster having a two-wire polarized cord (mine fits that description). Toasters include heating elements which are directly connected to both sides of the power line during the toasting process. These heating elements can and do fail, at which point the broken ends of the heating element flop around, potentially touching something connected to the case. In some such toasters, the case is connected to the neutral, so that should a point near the hot end of the broken element touch, directly or indirectly, the case of the toaster, it would blow the circuit breaker and turn off power. If that plug had been modified like your extension cord, there would be a 50/50 chance that the case would be connected to the hot side of the power line, putting anyone touching that case in serious danger.

Similarly, people commonly stick forks and knives into toasters to recover stuck pieces of bread etc. The switch that connects power to the heating element to turn on the heat MUST connect the previously disconnected end of the heating element to the hot side of the power line, so that when not toasting, all of that element will be at neutral voltage. Then a knife or fork touching the heating element will cause no harm. (Anyone sticking a fork or knife in there while it is toasting is on Darwin's list)

Finally. let me remind you that experienced folks like you and me forget things... LABEL that modified extension cord as NON-polarized, so six months from now you won't use it to power some other device that requires polarization for safety.

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#40
In reply to #39

Re: Polarized Extension Cord Feeding Non-Polarized LED Supply Cord

11/29/2017 7:17 PM

It has been a circuitous journey but, I believe we have arrived.

You are right about the adapter, but not using it would have meant that:

1. I had not thought the problem or the solution through correctly in the beginning

2. I had wasted time looking for that stinking adapter that I didn't need

3. I would then have had to put the adapter back, wherever I had found it (now, where DID I find this anyway?)

4. Admitting I was ever wrong is against my nature, and if you had just been quiet, my secret would still be safe.

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#42
In reply to #40

Re: Polarized Extension Cord Feeding Non-Polarized LED Supply Cord

12/07/2017 3:10 PM

Here's another item for your list:

It is the supply for an outdoor LED tree. I've used it before, but I used a different (non-polarized) extension cord this year, so only now noticed the polarized plug. This low-voltage AC power supply has a polarized plug for no obvious reason. It obviously takes 120VAC input and has a non-polarized 12VAC output, so it's just a transformer, and the output is isolated from the input, so there is no reason/need for polarization. I applied your solution...

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#43
In reply to #42

Re: Polarized Extension Cord Feeding Non-Polarized LED Supply Cord

12/07/2017 3:50 PM

I wasn't aware that LED trees needed watering.

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#11
In reply to #8

Re: Polarized Extension Cord Feeding Non-Polarized LED Supply Cord

11/27/2017 3:45 PM

Lyn,

I don't think the OEM thought that someone would put up a string of their lights and then attach an extension cord to the tail end of that string to power another string of their lights. I know this may go against all of the warnings and applicable laws but I say grind the cheapy cords polarity blade to the same as the other and go on with your day but you may want to put some kind of GFCI at the power end of the cord.

When I did lights last time, I used a roll of lamp cord and a bunch of center tap lamp cord taps along the length. I could power all the decorations from one line and the lamp cord all but disappeared in the Las Vegas grass (I mean rocks) in the front yard.

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#41
In reply to #11

Re: Polarized Extension Cord Feeding Non-Polarized LED Supply Cord

12/02/2017 2:28 PM

Not necessarily an extension cord. I've had the same problem with some outdoor Christmas trees that have polarized plugs I was unable to plug into the strings of LED lights nearby. Have to run separate extension cords to the trees or file the wider pin on the plugs.

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#3

Re: Polarized Extension Cord Feeding Non-Polarized LED Supply Cord

11/26/2017 9:34 PM

Probably because the actual light is fed through a driver and the AC line in just feeds the driver which doesn't care which tab is hot which is not....and likely it's produced for an international market....

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#4
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Re: Polarized Extension Cord Feeding Non-Polarized LED Supply Cord

11/26/2017 10:17 PM

And yet, to design a receptacle with a slightly larger slot on one side, regardless of the polarization of the conductors is a no brainer and would actually save a tiny bit of plastic for every plug.

These lights are obviously not made for use in the country of origin.

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#5

Re: Polarized Extension Cord Feeding Non-Polarized LED Supply Cord

11/27/2017 3:13 AM

<...Grounded?...> An appliance that has no exposed metallic parts doesn't need a Ground/Earth connection, as there is no risk of any exposed metallic part becoming live and therefore a potential electrocution hazard. In continental Europe this feature is marked on the appliance with a square-within-a-square symbol and one would expect the flexible supply cord to such equipment to have only two conductors, instead of three.

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#7

Re: Polarized Extension Cord Feeding Non-Polarized LED Supply Cord

11/27/2017 8:07 AM

AC Adapters are the same, unpolarized. Maybe they want to be compatible with the 0.1 percent of people that live in houses over 100 years old.

"NEMA 1-15 ungrounded (Type A)[edit]

Polarized (left) and unpolarized NEMA 1-15 plugs Main article: NEMA 1

NEMA-1 plugs, rated 15 A at 125 volts, are compatible with both NEMA-1 receptacles and NEMA-5 receptacles; NEMA-1 is ungrounded (no earth), while NEMA 5 is grounded. The plug has two parallel blades. Early versions were not polarized, but most plugs are polarized today via a wider neutral blade on the plug that fits a wider neutral opening on the receptacle. (Unpolarized AC adaptors are a common exception.)

Harvey Hubbell patented a parallel blade plug in 1913, where the blades were equal width (US Pat.1064833[78]). In 1916 Hubbell received a further patent for a polarized version where one blade was both longer and wider than the other (US Pat. 1180648[79]), in the polarized version of NEMA 1-15 both blades are the same length, only the width varies.

Ungrounded NEMA-1 outlets are not permitted in new building construction in the United States and Canada, but can still be commonly found in older construction. Allowed replacement of NEMA-1 receptacles varies by local code."

https://en.wikipedia.org/wiki/AC_power_plugs_and_sockets#Polarization

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#10

Re: Polarized Extension Cord Feeding Non-Polarized LED Supply Cord

11/27/2017 3:32 PM

How about one of these?

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#16
In reply to #10

Re: Polarized Extension Cord Feeding Non-Polarized LED Supply Cord

11/27/2017 8:45 PM

But be sure to cut off that annoying ring thing first. It just gets in the way.

(Kids, don't do this at home. I'm just kidding. But seriously, I have seldom seen ANYONE actually use that screw in the middle of the outlet plate to secure this to the outlet, let alone checking to see if the outlet box is even grounded in the first place. By the grace of the deity of your choice or not, we seem to survive anyways.)

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#32
In reply to #16

Re: Polarized Extension Cord Feeding Non-Polarized LED Supply Cord

11/29/2017 10:02 AM

In the garage that existed when I bought my house (it has since been demolished), the previous owner had installed a string of outlets along the wall. Having wired it in the early 1960's, they used the two hole NEMA-15 outlets. Instead of wiring the ground from the supply wire to the box to properly ground each box, they simply cut the ground wires. None of the outlet boxes was grounded! The little ring tab would have been useless in that situation.

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#37
In reply to #32

Re: Polarized Extension Cord Feeding Non-Polarized LED Supply Cord

11/29/2017 4:37 PM

That was exactly one of my points and your experience tells me that shoddy wiring is more universal than we would hope.

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#17

Re: Polarized Extension Cord Feeding Non-Polarized LED Supply Cord

11/27/2017 11:30 PM

After reading 16 replies, I'm still confused!

They weren't grounded/polarized because there was no need for them to be grounded/polarized.

Under normal circumstances, any extension cords required would feed power TO the lights, and it wouldn't matter whether the extension cord were polarized or not.

Apparently you want to use an extension cord to take power FROM one of those hermaphrodite non-polarized sockets to somewhere else. Once you have used any single non-polarized device, the rest of the circuit IS NOT polarized, so a polarized plug should NOT fit.

Of course, just as so many people break off the ground lug so a previously 3-prong plug will fit a a 2-prong socket, you can easily get out a file (as someone else mentioned) or a Dremel and reduce the width of the wide blade on the polarized plug, but that is indeed illegal and potentially unsafe/dangerous.

That's still a LOT safer than one that occurred to me a few years back: A neighbor had installed several strings of Christmas lights connected in series, when she realized she had placed the male plug at the wrong end. Rather than take them down and reverse them, she cut off the female socket at the connection end, and replaced it with a male plug. She realized that there was some danger with the male plug at the other end of the string, so she wrapped it with aluminum foil! Fortunately, she had the foresight to ask me to inspect her work before plugging it in....

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#18

Re: Polarized Extension Cord Feeding Non-Polarized LED Supply Cord

11/28/2017 3:05 AM

Ahah. Changing plugs isn't something wholly within the domain of the Electrical Engineer.

It comes as a surprise, actually, that SolarEagle hasn't yet provided a link to a video on YouTwitFace that shows how to do it.

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#19

Re: Polarized Extension Cord Feeding Non-Polarized LED Supply Cord

11/28/2017 9:42 AM

Anytime I've seen this, the device has no exposed metal parts, so grounding is not required. What would one ground on a plastic cased device? Once the company sees it can drop the third pin (ground), they go with the cheapest plug they can get, which is the old (1960's and before) standard plug. A non-polarized plug should work with a polarized extension cord. (I didn't read all the posts, so if this is an issue...although it shouldn't be) I've done this with several such lighting strings myself.

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#21
In reply to #19

Re: Polarized Extension Cord Feeding Non-Polarized LED Supply Cord

11/28/2017 10:21 AM

I thought the title "polarized cord feeding non-polarized LED supply cord" would convey the message that I was plugging a polarized plug's prongs into a non-polarized plug's socket.........................I knew exactly what I meant.

Oh well.

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#27
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Re: Polarized Extension Cord Feeding Non-Polarized LED Supply Cord

11/28/2017 1:19 PM

"polarized cord feeding non-polarized LED supply cord"

The term "feeding, to a controls engineer, implies the cord coming from the 120VAC to the device using this electricity. Hence the belief you had a polarized extension cord with female receptacle on the end in question and a non-polarized cord on the device utilizing the electricity, hence a male plug. You knew what you meant - I didn't.

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#28
In reply to #27

Re: Polarized Extension Cord Feeding Non-Polarized LED Supply Cord

11/28/2017 2:36 PM

"You knew what you meant - I didn't."

My wife might disagree that I know what I mean sometimes.

Yes, a polarized adapter would have been appropriate.

Necessity is the mother of invention and I had a two prong non-polarized adapter in my tool box.

The reindeer thank you all!

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#29
In reply to #28

Re: Polarized Extension Cord Feeding Non-Polarized LED Supply Cord

11/28/2017 3:07 PM

I just saw your post 20 and adapter hook up. You can be glad your in Phoenix where it seldom rains. That looks like a potential earthworm exciter in a rainier climate. I could use it here where I am - it would be under a foot of snow too cold to melt and on frozen ground. (well - maybe not this year - we're about 15 degrees above normal most of the days - lake "defects" should have been running by now, but are missing this year)

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#30
In reply to #29

Re: Polarized Extension Cord Feeding Non-Polarized LED Supply Cord

11/28/2017 3:19 PM

Before I retired we used to wrap 200 trees in downtown with strings of ungrounded lights, each plugged into a dedicated GFCI circuit. (They still do this)

After every rain, when things dried out, I'd send guy out to reset the ones that had tripped.

These reindeer are mounted on poles so it looks like they are flying. None of this runs on the ground after the first extension cord.

It's still in the 80's here and we are in drought conditions. I'd welcome rain. Obviously I water the grass.

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#33
In reply to #30

Re: Polarized Extension Cord Feeding Non-Polarized LED Supply Cord

11/29/2017 11:05 AM

"...still in the 80's here and we are in drought conditions."

Ahh, you obviously were shipped reindeer not RAINdeer. You should ask for a refund.

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#20

Re: Polarized Extension Cord Feeding Non-Polarized LED Supply Cord

11/28/2017 10:00 AM

So, here's the subject connector. No conventions have been violated, everything is plugged in as it should be.

The orange (female) extension cord feeds a non-polarized adapter, one plug, plugged into the socket of the orange cord and three sockets. The white plug/socket is non-polarized, no problem.

The brown. polarized plug is was the problem that I resolved by simply cutting the polarizing ears off both sides of the neutral side prong.

So, all plugs are mated with sockets and there are no exposed prongs.

But, the question remains, why not make one slot of of the female, non-polarized socket wider to accommodate a polarized plug?

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#22
In reply to #20

Re: Polarized Extension Cord Feeding Non-Polarized LED Supply Cord

11/28/2017 10:57 AM

Aha! According to this, your title is backwards! you have a non-polarized adapter feeding a polarized LED string. The extension cord has nothing to do with the problem.

Legally of course, the multi-outlet adapter should have been at least polarized, if not three-prong.

On the other hand, why did the makers of the LED string bother with a polarized plug, when there is nothing to polarize? I just checked a few of mine, and none of them are polarized.

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#24
In reply to #22

Re: Polarized Extension Cord Feeding Non-Polarized LED Supply Cord

11/28/2017 11:47 AM

No, no, no.

The lights and their connectors are NON-polarized. The two extension cords I am using are polarized. So, I needed to plug a male polarized plug into a female non-polarized socket.

I had to plug a non-polarized adapter into a polarized (orange) extension cord, no problem there.

But the non-polarized adapter, having one male plug and three sockets is also non-polarized. That necessitated that I trim the neutral lug of the polarized plug to fit the non-polarized adapter's socket, also plugged into the orange cord. The trimmed lug is just visible at the top of the picture.

For the record, it's working fine and trimming the lug took me all of 30 seconds.

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#26
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Re: Polarized Extension Cord Feeding Non-Polarized LED Supply Cord

11/28/2017 12:09 PM

Got it! There are TWO extension cords; the orange one is a standard 3-wire 3-prong cord, and the dark one under your thumb is a 2-wire polarized cord.

Again, the problem is the multi-outlet adapter. Either a 3-prong or a 2-prong polarized adapter would work correctly.

Since a polarized device could be plugged in to the female end of the 2-prong polarized extension cord, then only a polarized or 3-prong adapter is appropriate.

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#23

Re: Polarized Extension Cord Feeding Non-Polarized LED Supply Cord

11/28/2017 11:00 AM

Is this a homework question?

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#25
In reply to #23

Re: Polarized Extension Cord Feeding Non-Polarized LED Supply Cord

11/28/2017 11:57 AM

Yes, I'm applying for an electrical contractor's license and it's a test question.

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#31
In reply to #25

Re: Polarized Extension Cord Feeding Non-Polarized LED Supply Cord

11/28/2017 6:52 PM

Was that for substation design work?

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Power-User
Engineering Fields - Electrical Engineering - Hmmm...

Join Date: Jul 2010
Location: Maryland
Posts: 494
Good Answers: 26
#34

Re: Polarized Extension Cord Feeding Non-Polarized LED Supply Cord

11/29/2017 11:10 AM

If they polarized the socket at the end of the string, they'd also need to polarize the plug at the beginning of the string. Without polarizing the plug, there's no way to ensure that the socket is correctly polarized.

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Guru

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#35
In reply to #34

Re: Polarized Extension Cord Feeding Non-Polarized LED Supply Cord

11/29/2017 11:23 AM

These are NOT polarized now. There is no reason to polarize them. The socket does not require polarization, just enlargement of the slot. There is ONLY one plug/socket on each string, not two.

The un-polarized male plug will fit either polarized or non-polarized sockets so what's wrong with just enlarging the slot without doing anything else, anywhere. Then a polarized plug would fit the socket without having to have one prong hacked down to fit.

Maybe it's my use (or mis-use) of the language, I'm not an electrician, nor an electrical engineer, but I can't understand why what I'm saying does not seem to register with anyone else.

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