So... Why aren't my Deans plugs melting?

[NativePaul]

10 minute runs are the key here, what capacity batteries are you using? if you running 5000mah 1p a 10 minute run is only an average of 30A if your running 5000mah in 2p for a total of 10,000mAh its still only 60A, just within the spec of deans.

The patina forming may just be the chinese deans gold plating being too thin and getting scrapped off, you might find actual deans have a thicker layer of gold and last you longer, gold itself is inert and wont oxidize under any conditions, which is why it is used for connectors despite its cost and poorer conductivity compared to the cheaper alternatives, silver and copper.

[FighterCat57]

Am I reading this right that you have been using the deans in cars at 100A? There is a big difference in the discharge between cars and boats, I run 1/8th scale cars as well as boats and having datalogged both I can say they are not at all comparable, while my cars pull 120A peaks that peak lasts less than half a second and then it steadies to a decreasing burst for as long as the throttle is held and there are frequent periods of no throttle at all, so the average amp draw is about 25A, in boats set up for the same 120A peaks the peaks are much more frequent and the whole run is the burst either not lifting off for the entire run or just lifting for a split second twice per lap depending on the hull, I will average about 80A putting over 3 times the load on the connectors.

I guess the context might be confusing a little since I referenced my cars in this. The original question is asking why the Deans connectors don't get hot or melt in my boats pulling 139+ amps peak on 10 minute runs. Don't know the constant, my meter only holds peak and current, but can't be more than 50-60c, that's all the packs are rated for.

Curious why they have held up so well.

One thing they do really fast here though is turn green from the moist salt air. Anything with positive ionization starts to grow in minutes around here...

I'm most likely going to use a dielectric grease on the bullets to help prevent this.
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American Dad! Dicussion

[NativePaul]

Am I reading this right that you have been using the deans in cars at 100A? There is a big difference in the discharge between cars and boats, I run 1/8th scale cars as well as boats and having datalogged both I can say they are not at all comparable, while my cars pull 120A peaks that peak lasts less than half a second and then it steadies to a decreasing burst for as long as the throttle is held and there are frequent periods of no throttle at all, so the average amp draw is about 25A, in boats set up for the same 120A peaks the peaks are much more frequent and the whole run is the burst either not lifting off for the entire run or just lifting for a split second twice per lap depending on the hull, I will average about 80A putting over 3 times the load on the connectors.

[LiPo Power]

Way to go and 10g wire also also help.
I just swiched all my boats connectors to 5.5mm bullet.

FYI- I'm not having any problems with the connectors to my knowledge... But if I'm chasing around current/draw issues, I'm certainly going to be removing any potential current draw, like an underrated connector.

Like in this instance, I just removed the connectors completely and soldered in an X harness. I believe the resistance in a soldered connection is less than that of a connector. I made sure the solder did a nice flow throughout and all around.

The solder doesn't stick to the wire tie, it flows right around it.

Now, I only have the pack connectors and motor connectors. No "Y" or "H" connectors to worry about.

[FighterCat57]

FYI- I'm not having any problems with the connectors to my knowledge... But if I'm chasing around current/draw issues, I'm certainly going to be removing any potential current draw, like an underrated connector.

Like in this instance, I just removed the connectors completely and soldered in an X harness. I believe the resistance in a soldered connection is less than that of a connector. I made sure the solder did a nice flow throughout and all around.

The solder doesn't stick to the wire tie, it flows right around it.

Now, I only have the pack connectors and motor connectors. No "Y" or "H" connectors to worry about.
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Dodge custom 880 history

[BILL OXIDEAN]

when you pull 120A is it constant?
I bet they are rated at 60A with some safety, I use them on my 29"mono/8XL/4S and they do get warm but that's it, I'm pulling 70 to 80A constant, 100A burst!

without reading the whole thread, this answer sounds logical.
many SERIOUS high speed high current projects have been executed with Deans, especially with cars.

Not saying they're the best plug for high current apps, only saying they can handle a suprising ammount..

[AndyKunz]

A lot of guys just use heat shrink over the EC5's.

Andy

[FighterCat57]

Good replies.

It's always an interesting subject when talking about technical aspects of things. Seems the more you learn, the more there is to learn.

I went with the deans mostly because a bag of 100 was like $20 from some place in China a few years back and still haven't run out...

I bought a couple dozen EC5 connectors a while back when I started using Lipos, but didn't like how bulky the connectors are... I still have about 40 individual 5mm bullet sets... I might start using these without the housing on bigger setups that are drawing a constant rather than burst current. I think the final resting point for everything is going to be 5.5 or 6mm polymax type bullets.
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Honda cb250 jade specifications

[scooterP]

My deans were de-soldiering constantly when running a 12L in my SV. I just figured that they could not handle the amps. I don't have any type of data logger to tell what I was pulling. I switched over to 5.5 bullets and no problems since. It's also easier to hook up batteries in series with bullets.....for what that is worth to ya....

[domwilson]

Here is some good reading on the subject... http://forums.offshoreelectrics.com/...tor+resistance

[crabstick]

A Guy in our club was melting the solder off his deans connectors nearly every race with his supervee on lipos.. the races are 5 laps of a full Gas/Nitro Course... might be a bit different from the odd 10 second burst

[Fluid]

The Deans plastic is a good heat insulator and is resistant to heat, it's the metal connector parts that matter. By the time you can 'feel' connectors they have already cooled off anyway.

The Deans are relatively high resistance and you are losing performance due to the voltage drop across them compared to good 5.5 gold connectors. Too, the Deans connectors degrade rapidly with use, increasing their resistance substantially. But run whatever you want, it's your boat....



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[Raydee]

Wire size is a huge factor too. I hate to sound like a broken record but in the Heli forums a well known guy there did a test on different size connectors and wire and in all cases the wire size was the most important factor in resistance and heat. I imagine fitting 10g wire on a Deans connector isn't the easiest thing to to, that is probably why most would rather use bullets with that size wire.

[FighterCat57]

Hmmm. Full throttle is usually no longer than 10 seconds, maybe 20 seconds on some of my cars. They hit about 140a and are all using 10ga wire.

Maybe that's it. Maybe it's a constant amp rating rather than a threshold?
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TOYOTA CAMRY TS-01 HISTORY

[Raydee]

The deans themselves won't melt but I bet IF you are really pulling 120amps continuous you will either melt the shrink on your wires or your wires will run very hot. When I ran my 4s rigger with Deans all the esc and batt wires would run hot, that was a 90amp setup. After switching to 5.5mm bullets everything ran cooler in the setup.