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odie

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I've had various heating elements in the past actually fuse plugs together. I use heavy gauge extension cords but I have experienced where a 1500 watt heater would fuse with the ext cord after extended use.

For example, I have a 1500 watt immersion heater (not for brewing) that has permanently fused to an extension cord. The heater is 16AWG (yeah, kinda small) and the ext cord is 12AWG 10 foot. I didn't have any grease applied.

Another time it was on my kettle. 1500 watt element with 10 gauge pigtail and 12 AWG ext cord and it fused after running a couple hours. again, no grease.

I'm using dielectric grease now but have just read that it is not conductive??? So it's not helping to lower the resistance (which was probably the cause of the heat and fusing).

Is there a better or "conductive" grease to use to help reduce any resistance at the plug connections to help prevent excessive heat and fusing?
 
A couple questions: Is there a switch somewhere, or is there current running immediately when it's plugged in and arcing?
Have the terminals been cleaned? (I like emery boards...you can use side-cutters to make thin ones fit inside receptacles)
Do the plug and receptacle fit snugly together or ar they cheap and loose-fitting?
 
both switched and unswitched. new clean terminals. snug, not loose.

but they are energized for extended periods of time for various applications. Hours, not minutes.
 
Another time it was on my kettle. 1500 watt element with 10 gauge pigtail and 12 AWG ext cord and it fused after running a couple hours. again, no grease.

I'm using dielectric grease now but have just read that it is not conductive??? So it's not helping to lower the resistance (which was probably the cause of the heat and fusing).

Is there a better or "conductive" grease to use to help reduce any resistance at the plug connections to help prevent excessive heat and fusing?

https://www.sanchem.com/electrical-contact-lubricant.html
I use this on my boat for high-current connections.
Also, make sure your connections are clean to start with.

But I'd also suggest getting the wire gauge right through the entire circuit.
 
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Is it the plastic bodies of the plug and receptacle that are fused together, or are the metal contacts welded together? Plastic melting would indicate high resistance (poor) contact which causes local heating. Metal welded together would likely be due to arcing between contacts.

I doubt the smaller than optimal wiring is a factor. Too fine a wire will cause excessive heating all along the wire, not just at the connection points, which is what caused OP's issues. That said, using too fine a wire gauge can cause problems of its own.

Brew on :mug:
 
Is it the plastic bodies of the plug and receptacle that are fused together, or are the metal contacts welded together? Plastic melting would indicate high resistance (poor) contact which causes local heating. Metal welded together would likely be due to arcing between contacts.

I doubt the smaller than optimal wiring is a factor. Too fine a wire will cause excessive heating all along the wire, not just at the connection points, which is what caused OP's issues. That said, using too fine a wire gauge can cause problems of its own.

Brew on :mug:
that's what I would think but it seems to appear that where the plastic parts touch are not fused. well, at least where I can see...

but any connection point is a point of likely reduced connectivity and increased resistance...a focal point of heat is the result
 
"Dielectric grease" as a generic reference is non-conductive.

I would not apply unless you are trying to add some degree of protection against moisture/corrosion or the contacts are of a nature subject to fretting corrosion where a bit of lube might help prevent that.
 
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both switched and unswitched. new clean terminals. snug, not loose.

but they are energized for extended periods of time for various applications. Hours, not minutes.

If these are the molded on plug and receptacle, might want to consider trying high quality commercial or hospital or industrial grade replacements from Hubbell et. al.

They are not inexpensive but they are tight fitting and remain so over longer time.
 
IMO, contact goop may not be of much help/bandaid if the contacts are not really all that tight.

The integral molded plugs and receptacles often are not really tight in a relative sense especially after some use and even moreso if ovetheated. Considering the seeming/potential continuous use (NEC defined as 3 hours or more) 80% rule, 1500W is techically in excess of that for 15A plugs (and IMO particularly re. cheap ones like typical molded ends).

Repeating myself here but I'd sure look at replacing the molded plugs and receptacles with quality ones for long duration, high current (relative to rating) use.
 
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IMO, contact goop may not be of much help/bandaid if the contacts are not really all that tight.

The integral molded plugs and receptacles often are not really tight in a relative sense especially after some use and even moreso if ovetheated. Considering the seeming/potential continuous use (NEC defined as 3 hours or more) 80% rule, 1500W is techically in excess of that for 15A plugs (and IMO particularly re. cheap ones like typical molded ends).

Repeating myself here but I'd sure look at replacing the molded plugs and receptacles with quality ones for long duration, high current (relative to rating) use.
Very often, people use the cheapest components to build homebrew setups. This is compounded when that is the prime driver for picking a component and all components are of low quality. In addition, the often lower quality component is push to or beyond it's limits.

People often post about a SSR failure and will use a mechanical relay a disconnect if the component fails. A good quality Crydom SSR that is properly sized, (meaning if you have a 25 amp load, a 50 amp component is selected), with a properly sized heat sink will have a MTBF (mean time between failure) between 800 and 1300 years. They never fail unless they are hit directly by lightning. If a good quality SSR is used on each leg of the source, the mechanical relay is not necessary and has a higher failure rate than the SSR it's protecting.

The dielectric grease is non-conductive, as it's name implies. No grease will improve the conductivity of a mechanical connection. It is used to reduce corrosion in either wet areas or between two disimular metals (aluminum and copper).

Size your components correctly and buy quality components and you will have years or decades of trouble free brewing.
 
While I don't like maxims or cliches, a couple have always stuck with me including one from my older brother: "If it jams; force it. If it breaks; it needed replacing anyway."... I kind of combine that with the one most deeply impressed upon me: "Buy once, cry once." While I try not to buy things that can't be taken apart as a general rule, there have been many things that I don't like the design of but bought anyway for it's components so I can tear it down and make what I actually want. I noticed in your other posts that last August you were thinking about upgrading your heating element and am wondering if this immersion heater was a supplement you settled on? If so; I'd say try and get back in the mindset you had in August and reconsider a more powerful element or: take a chance on breaking this and find a way to take it apart to bring to wire up to the spec your application requires.
:mug:
 
the immersion element has nothing to do with my brewing. it was for another application. the gauge of my ext cords and pigtails I've used in my brewing system are more than sufficient for the current. They were not "cheap" to buy.

The question was specifically about where there the male/female plugs meet...those are not permanent connections and thus a focal point of increased resistance.

Other than a tight/snug fit, was there any type of conductive "grease" that might help minimize the resistance to electrical flow. Kinda like how a paste is used for a Peltier chip to improve thermal conductivity.

If such a conductive compound does not exist, then fine. Then just make sure the plug fit is snug/tight is about all anyone can do.
 
Dunno if the links will show up, I'm in Canada and amazon always redirects to the .ca site... the link you provided above worked for me but as the product had no reviews I looked at the same product from other sellers and among those with reviews there seems to be a number of failures, including the one you're experiencing.
Here's one such listing:
https://www.amazon.ca/Intelligent-T...ea-a8eb-d9d02bb87be4&pd_rd_i=B0B7H5MDSS&psc=1
..if the link doesn't work, here's a quote from one of the reviewers:
"- other notes about electric heater . I had it plugged into an amp , watts , monitor to see what it pulled during use.
It pulls 14.6 amps the whole time and 1760 watts"

..and here's a couple pics:
81fNWXxzZNL.jpeg

81tPXo1W5ZL.jpeg

Maybe you just got stuck with a bad unit... is it too late to get a refund? In any event; I wouldn't use 16 gauge wire for a 1750W heater load personally.. is it impossible to take apart?
 
Dunno if the links will show up, I'm in Canada and amazon always redirects to the .ca site... the link you provided above worked for me but as the product had no reviews I looked at the same product from other sellers and among those with reviews there seems to be a number of failures, including the one you're experiencing.
Here's one such listing:
https://www.amazon.ca/Intelligent-T...ea-a8eb-d9d02bb87be4&pd_rd_i=B0B7H5MDSS&psc=1
..if the link doesn't work, here's a quote from one of the reviewers:
"- other notes about electric heater . I had it plugged into an amp , watts , monitor to see what it pulled during use.
It pulls 14.6 amps the whole time and 1760 watts"

..and here's a couple pics:
View attachment 877941
View attachment 877942
Maybe you just got stuck with a bad unit... is it too late to get a refund? In any event; I wouldn't use 16 gauge wire for a 1750W heater load personally.. is it impossible to take apart?
yes, impossible to take apart. the wiring is sealed cause it's submersible. but that is not the issue. It was strictly at the connection plug.

anyway, the heater may use a 16 gauge cord but I'm using 10 and 12 gauge extentions. thats an "orange extension cord" in the picture...those are typically light duty...around 16 gauge. and no telling how long...distance increases resistance. In that case the guy used a cheap cord...

heaters should not use extention cords typically...I use only heavy gauge ones for those kinda loads if I do. And the shortest length possible.

Time is also a factor. they are not meant for continuous duty.

Something else I've noticed recently...the female receptacles on extension cords vary. Some allow much more metal-to-metal contact (face to face)...You have to get a close up look into the blade slot. Some have minimal "cross contact"...think "scissoring" for lack of a better way to describe it. Or think of how you put your hands together to pray verses doing Spock's "Vulcan V-sign" with both hands and then sliding them together.

That's how my last 12 gauge heavy duty extension cord was when it fused the plug. I now take a close look at the female slots...there IS a huge difference. Heavy gauge don't mean anything it the actual connection point is small.

Paying close attention to the inner design of the female plug has not resulted in any more issues so far.
 
now that I think about it....both....actually three different cords have fused with various 1500 watt heaters....all from Harbor Freight. they were 12 gauge "heavy duty" with the crappy female blade design.
 
I've had my share of bad experiences with crappy receptacles.... I dunno if these have changed since the 80's, but the folding leviton replacement plugs/recptacles were my favourites because of the snug perfect union and the largest surface area contacts out of what was usually available at the hardware store:
https://www.homedepot.com/p/Leviton...ctor-Yellow-5359-VY-5359-VY/301304937#overlay
You could give one of those a try but keep in mind; undersized wire on a heating element becomes a heating element itself. If a decent plug with full-sized contacts fuses after you replace it, there is no other cure than replacing the wire. I do recommend those leviton plugs though, as long as they haven't cheaped out in the last 30 years.
:mug:
 
I've had my share of bad experiences with crappy receptacles.... I dunno if these have changed since the 80's, but the folding leviton replacement plugs/recptacles were my favourites because of the snug perfect union and the largest surface area contacts out of what was usually available at the hardware store:
https://www.homedepot.com/p/Leviton...ctor-Yellow-5359-VY-5359-VY/301304937#overlay
You could give one of those a try but keep in mind; undersized wire on a heating element becomes a heating element itself. If a decent plug with full-sized contacts fuses after you replace it, there is no other cure than replacing the wire. I do recommend those leviton plugs though, as long as they haven't cheaped out in the last 30 years.
:mug:

I second the recommendation for Leviton, or other major brand, over cheap generics. Had a similar experience with lamp sockets where the contact "springs" in the cheap generic had no spring quality at all, took a set, and pretty soon contact with the base of the bulb was intermittent and unreliable. Replaced with a Leviton, and haven't had problems since.

Undersized wire will generate excessive heat (and power loss) in the wire, but that heat will be distributed along the entire length of the wire. It would be very unlikely that it would get hot enough at the plug to melt the plug. A melted plug is an indication of poor (= high resistance) contact in the plug/receptacle, which will generate heat at the connection.

Brew on :mug:
 
I would have to see the inside of the Leviton plug to judge the connection capability.

was at Lowes yesterday...looked at their heavy duty Ulilitec brand ext cords...

the single plug ones had good female receptacles...the triple taps had crappy receptacles with minimal contact points. Very strange.

I strongly suggest y'all peer deep inside your extension cords. "heavy duty" or "10 gauge" won't mean a thing if the contacts are crap.
 
I would have to see the inside of the Leviton plug to judge the connection capability.

was at Lowes yesterday...looked at their heavy duty Ulilitec brand ext cords...

the single plug ones had good female receptacles...the triple taps had crappy receptacles with minimal contact points. Very strange.

I strongly suggest y'all peer deep inside your extension cords. "heavy duty" or "10 gauge" won't mean a thing if the contacts are crap.
I'm just curious; As the plug on the heater has arced already, have you just filed it clean or will you be replacing both the male plug and female receptacle on the extension cord? It's been such a long time since I last bought a replacement cord-plug, the Levitons were still made in the USA.... I dunno if they cheaped out when they moved production to China. Can you do a favour to those of us on here that are interested?...When you buy replacement(s), take some pics of the internals and share them with us on here please.
Best of luck, and keep us updated however it goes.
🔌⚡:mug:
 
the immersion heater that fused to the extension cord...it's basically permanently connected. And it's not for my brewing anyway. I just now have a "longer" power cord for that heater...

The other extension cord was a "triple tap". Now I don't use the middle receptacle anymore. But it is no longer used for high current applications due to the inferior receptacle design.
 
here is a comparison of the female receptacle designs. one type has much more contact surface than the other. They are exactly the same brand and gauge. only one is a single outlet and the other was a 3 outlet. I suspect most triple/multiple tap extension cords will use the bad design...I assume due to the complexity and expense of the superior receptacle. They can use a single flat bar to make 3 connections instead of 3 individual "proper" connectors.
Both were labeled as the same power (watts) handling capacity...even though one is clearly not as good as the other.

20250617_162127.jpg
20250617_162148.jpg
 
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Here is another view angle of the multi tap receptacle that shows how minimal the contact area is...avoid these type extension cords for high current use.
20250617_162205.jpg
20250617_162136.jpg
 
Thanks for the close-up pics! I actually bought 3-outlet a cord pretty much like that one, but I never looked at the receptacles because I cut it off so I could use the higher gauge wire that was cheaper than buying cord by the foot.
.... I'm gonna have to go look at the last extension cord I bought for my lawn tools (to replace the old one my GF cut through [twice :p ] using the hedge-trimmer.
 
..OK... your pics made me go dig out the 'pigtail' I'd saved in the event I ever need it. Like I mentioned previously; I often buy things for the components and I bought this cord just for the wire and replaced the plugs with L6's. ...looks like the exact same cord, here's mine;
IMG_1788.jpg

IMG_1789.jpg

Ok...not the best pic, but it's the same minimal contact area in a single bent and slotted bit of cheap metal...straight to the trash!
I can easily see now why your plugs would arc together!
 

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