daddycool

Is it worth using better connectors when running nimh?

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Hi

is there any benefit to fitting deans or XT60 connectors with a nimh battery?

Ill be running an 80A esc and 13.5 brushless in one car and standard tble02s and torque tuned in another

Thanks, Kristian 

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There isn't really as far as performance or risk of melting the connectors goes. I have swapped mine to XT60 because all my batteries can use XT60 plugs (most of my lipos have bullet plugs, so i have discharge leads with XT60), and my chargers use them too. It makes sense to me to use a standard plug for all cars. Lipos won't come with tamiya plugs so if/when you do change you will need to do something. 

In saying that, I could have left my NiMH and TBLE-02S eith the Tamiya plugs and just made some adapters for my charge leads.

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The Tamiya plugs ain't really power efficient and robust so yes there is a benefit. I swapped all to XT60 and those have a much better handling and tend to get less hot. Also swapped the Tamiya motor connectors to 4mm gold plugs or straight soldered esc to motor.

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BITD I managed to melt several Taniya connectors running NiCd batteries.

I'd say it's definitely worth changing them if running anything other than a silver can.

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13 hours ago, daddycool said:

Hi

is there any benefit to fitting deans or XT60 connectors with a nimh battery?

Ill be running an 80A esc and 13.5 brushless in one car and standard tble02s and torque tuned in another

Thanks, Kristian 

When it comes to choosing connectors, it is more important to consider your motor than your battery. A low-turn motor can fry Tamiya connectors on a NiMH battery, while a high turn one is quite safe with Tamiya connectors even on LiPo.

That said, I agree that there is an advantage to upgrading your connectors even on high turn motors and NiMH, as a good connector will have lower resistance which translates to better performance.

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Are there good and bad xt60 and gold plugs or are the cheap ones on eBay as good as anything else 

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17 hours ago, daddycool said:

Are there good and bad xt60 and gold plugs or are the cheap ones on eBay as good as anything else 

If you actually want to pull 60A constant then yes, avoid the cheap ebay ones as they won't do it without melting. The plastics of many of them are not as heat tolerant as the real thing and the contacts aren't machined to as tight tolerances resulting in a poorer fit, higher resistance and therefore more heat. Maintaining that kind of constant current draw in a car pretty much implies that you have a 100A+ esc and really hot motor because to make up for the time when you're not on full throttle you need to be pulling way more than 60A when you are going full throttle. If you had a 5000mAh battery pack, maintaining an average of 60A current draw would imply that the car only takes 5 minutes to completely drain a pack. 3000mAh would drain in 3 minutes and so forth.
It's more common in RC aircraft and boats to pull high constant current since they spend far more time at wide open throttle and the water/air resistance provides much more load on the motor than a typical car setup faces cruising at top speed. Buy from Hobbyking if you want the good ones as they (actually their parent company heXTronik) invented XT plugs.

For a 7.2V NiMH pack that is lucky to put out 20A for more than a few seconds without the ESC throwing it's hands in the air due to voltage drop in the pack itself, the cheap XT60s will be fine. Still better than a Tamiya connector.

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On 7/7/2019 at 10:17 PM, Peter_B said:

BITD I managed to melt several Taniya connectors running NiCd batteries.

I'd say it's definitely worth changing them if running anything other than a silver can.

Have done the same. Replaced with Deans and no more issues. Now I use XT90s, but in hindsight XT60s would have been fine.

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Benefit?  Yes.  

Worth doing it?  A "definite YES" for 13.5t.  "Maybe not" for torque tuned (but as Jonathon said, I'd switch both to save myself some trouble).    

XT60 is rated for 60A burst (30A constant).  Your ESCs are 80A and 60A (TBLE02S) burst.  But Tamiya connector is rated for just 1A constant (maybe 2A burst).  So.... yes, Tamiya connector can melt.  But if you only had Torque Tuned, it will draw less than 1A constant, maybe 1.2A on burst.  So, Tamiya plug will do just fine for that particular motor.   

However, 13.5t can draw a lot more power. (My guess is about 3A constant)  If you are doing wheelies? Or climbing an uphill with tall gearing?  Such "abuse" could draw like 4A, and Tamiya plug can melt.  I've had one melt in the casing too in the past. All I had were Sport Tuned (which shouldn't draw 2A on burst).  13.5t drinks a lot more juice than Sport Tuned.  So for your 13.5t, I'd go with XT60 (or Deans; which are tiny, but nowadays they have a finger-friendly version).  

It's true that NiMH can supply less amp than LiPo.  The amp drops quickly.  When you gun it, the amp will shoot up like 4-5A.  Under 1 second, it will drop down to 2A.  LiPo will still give you 3A after 1 second.  Which is why LiPo of the same rating seems faster than NiMH.  Still, going over 3A isn't hard... even for a NiMH battery. 

When you solder, Never cut 2 battery wires together.  Your wire cutter will melt.  1) Cut only one wire, leave the other one still connected to the Tamiya connector.  2) Connect the cut wire to the XT60 or Deans.  3) Secure the soldered part with a shrink tube.  4) Only then, cut the other wire from Tamiya connector. 5) Solder that to the new connector.  

I paint the positive side red with a Sharpy pen (because I never underestimate my boundless stupidity--no, it doesn't go away with age and experience).  

7THwfoz.jpg

Talking about my stupidity, please take a look at a melted Swiss cheese (I mean knife). 

I was trying to pry off a pair of T-plugs.  My fingers just didn't get enough grip on those tiny things.  Instead of yanking hard on wires like a sensible person (I'm kidding! No yanking!), I tried to pry them off "carefully" with a flat head attachment... POP!  A spark melted the steel.  So... you can see why I'm not a fan of cheap T-plugs.  Good genuine Deans plugs shouldn't be that hard to unplug. I just don't know the quality of stuff that other people bought, before they sold their RC cars on Ebay. 

On the other hand, XT60s I got from Amazon are tight enough to dangle a battery for a year (why would you though?) but still consistently unplugged with a small effort.  

IrP9c4K.jpg

 

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