Changing connectors on my Lipo batteries

[Adrian Smith 1]

Those of you who have been following my Goldwing Corvus 60cc thread will know that the 5000mAh 6S lipos have XT60 connectors on like so:-

For safety sake I want to solder some EC5 connectors in their place.

Now I am happy with the way I solder EC5s in the normal run of things, but here is what I need a bit of guidance on.

What the best way to remove the XT60 connectors? I accept that under no circumstances should the bare wires touch each other. I did think I would just cut the plug off and insulate each wire after cutting before re-soldering each in turn, but I wonder if there is an easy way of removing the connectors thereby saving shortening the Lipo wires?

[Steve Colman]

With safety in mind of course as you indicated.

You could carefully remove/cut away the heatshrink from one wire and then simply desolder it from the connector.

Insulate the wire and repeat for the other.

Job done.

Edited By Steve Colman on 22/12/2017 17:32:00

[Chris Walby]

Just do one at a time so

Unsolder the red cable from XT60 and solder EC5 bullet

Then fit to blue holder

Unsolder the black from the XT 60 and solder EC5 bullet

Then fit to blue holder

Now here is the tricky bit!

Depending where you got the EC5 from the bullets either fit in the top or pull through from the bottom!! the sometimes have a chamfer on the bullet which shows which way the go in.

If you don't want the XT60 connector you can leave the soldering on a bit longer. The other thing is I use a gas torch for the EC connectors so not to get solder on the outside of the bullet.

[Dave Bran]

Why do you consider the XT60 unsafe?

[Steven S]

My last battery came with an adapter connector. It fit very tight and works for me.

https://www.venompower.com/collections/battery-device-plugs

Edited By Steven Shaw on 22/12/2017 18:02:49

[Graham R]

Out of interest what do you find unsafe about xt60’s. I changed over to them from 4mm bullet connectors as I found them to be unsafe (male pins only protected by fuel tubing).

Edited By Graham R on 22/12/2017 17:57:40

[Martin Whybrow]

I consider the XTs to be one of the best battery connectors for the purpose and certainly don't consider them unsafe.

[Tim A]

Why change from XT60's? Just changed all mine that were using HXT 3.5mm connectors over to them for safety HXT's can be misconnected i.e. you can short batteries together ask me how I know. If it's current load you are worried about XT's seem to be able to handle loads in excess of 60 amps easily I see others in my club using them on up to 8s batteries. if it's arcing on connection you are worried about no standard connector will avoid it whether it be XT', HXT, EC3, Deans, or Bullets.

[Geoff S]

XT60 connectors are fine but I understand they are only specified as OK up to 60 amps. Over 60 amps they may overheat and there may be a voltage drop (hence the heat - V^2/R). I guess if anyone has an application where very high currents will be drawn a different connector should be chosen.

As to swapping connectors safely - I usually cut one wire close to the connector and solder it to the new one, then, after insulating it (heat shrink usually) do the same with the second. I always used 4mm bullet connectors on all my LiPos so changing connectors became the norm for me.

I eventually succumbed to HK's pressure, bit the bullet, and converted all my 3S LiPos to XT60 (as well as all the ESCs). I continue to use 4mm bullets on my 4S LiPos as well as the solitary 6S but none of them draw huge amounts of current (ie >60 amps) and would probably be OK with XT60s.

Geoff

[Adrian Smith 1]

As to why I considered changing them? Given I am using the lipos in a 12s setup using 2x 5000mah batteries it was pointed out to me on this very forum on the Corvus thread they are not up to the job due to current drawn. Is that wrong then? Believe you me I would rather not change them! Just trying to get clarity here. Thanks guys by the way for helpful words in case I have to do it.

[McG 6969]

I would be in total accordance with Geoff's statement.

I'm converting - slowly - what I need to XT30 for 2 & small 3S and XT60 for heavier use up to 60A.

If one goes up to larger stuff like heavy Amp rated 5 or 6S, why then not use the XT90 with a spark protector?

The EC5 will not give you any mean of avoiding a spark when connecting them.

@ Geoff > I guess there was absolutely no real 'pun intented' when you wrote that you "bit the bullet"... ?

Just my 2 euro-cent anyway.

Cheers

Chris

[Tim A]

This thread got me wondering as to what load each type of connector is?

A quick searched came up with the following for constant load of these connectors.

XT60 = 60amps

XT90 = 90 amps

EC3 = 60amps

EC5 = 120 amps

Deans = 50 amps

Traxxas = 100 amps

Anderson = 30 amps

HXT 4mm = 93 amps

Interesting as a search on RC Groups showed a lot of people seem to be misinformed about Deans & Anderson types especially, although Andersons were only one that had a max voltage given of 600volts for those of you flying 3 phase mains voltage Haha.

[Andy48]

I also got rid of all my EC3 connectors and changed to XT60 when I found one of the connectors had pushed back out of the blue housing and barely making contact, only to let go just after I'd taken off. Thankfully the long grass prevailed.

[Andy48]

Posted by Adrian Smith 1 on 22/12/2017 18:48:48:

As to why I considered changing them? Given I am using the lipos in a 12s setup using 2x 5000mah batteries it was pointed out to me on this very forum on the Corvus thread they are not up to the job due to current drawn. Is that wrong then? Believe you me I would rather not change them! Just trying to get clarity here. Thanks guys by the way for helpful words in case I have to do it.

Looking at the motor spec, it will draw 130amps max. It looks like you will certainly need at least XT90s for connectors. However, as your batteries are only rated at 20C that would give a max current of 100amps. Running them at that will dramatically reduce the battery life. Were it me, then I'd be fitting XT90s to the batteries and ensuring the maximum current draw was no higher than around 75amps, by reducing the propeller size.

Edited By Andy48 on 22/12/2017 20:12:12

[onetenor]

When fitting Bullets I reverse the direction of the males and females to avoid shorting when coupling up.Works for me .

[Former Member]

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[Adrian Smith 1]

Too right, Tom. And interesting!

It is not the worry about arcing when connecting them that I am looking at because there is a chunky AS150 anti-spark connector in the circuit which is connected last and does that job very well. As to propellor size I will be using a 24X8 JXF wooden prop that was supplied by George at 4-Max which is about mid-range for the motor if the spec is anything to go by.

I just find it interesting the batteries were supplied with XT60 connectors which was why the whole question of fit for purpose was raised in my mind. This particularly as my Hacker 4500 mAh 6S lipos are supplied with EC5s on them. I notice, by the way, in Kiwikanfli's table an EC5 is good for 120amps which in my simple mind give a good safety margin in the 12S setup I am using.

If I am talking out my hat do tell as I never took too much interest during my old physics lessons!

[Former Member]

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[Andy48]

Posted by Adrian Smith 1 on 23/12/2017 07:18:54:As to propellor size I will be using a 24X8 JXF wooden prop that was supplied by George at 4-Max which is about mid-range for the motor if the spec is anything to go by.

At the end of the day, simply relying on the prop given is the wrong way to go about things. You need to measure the maximum current with that prop and work from there. If you try and pull 130amps out of the batteries you have bought they will have a very short life indeed being only 20C. You will probably need a more specialist watt meter to measure this that will handle the currents involved.

This consideration is far more important than the choice of connectors at this stage.

[Martin Harris - Moderator]

Posted by onetenor on 22/12/2017 23:37:47:

When fitting Bullets I reverse the direction of the males and females to avoid shorting when coupling up.Works for me .

It seems to me that with bullets, you have to choose between the safer female/female battery terminal connection method which jeopardises the ESC if you get it wrong or the male/female which jeopardises the operator, batteries and model.

My "solution" when I used bullets was to adopt the latter (your method) but slip heatshrink over the two wires to hold them together close to the terminals so that it was impossible to connect the battery leads together without some serious effort.

[Adrian Smith 1]

I had a productive morning after deciding no more cogitating, flatulating or any other .. ating for that matter, and got on with fitting the EC5 connectors.

Job done on both batteries and seemed to go well.

I take your point Andy48. That said and given the low cost of them, I am not expecting much of a life out these two lipos. They are probably only going to be used for a few test flights thereupon I will revert to buying the equivalent capacity Hacker TopFuel lipos which is my preferred brand. Nevertheless this exercise has been an interesting learning curve if only to appreciate how many differing/alternative views are to be had on this forum.

[Adrian Smith 1]

Quite right, Percy. They are a great shop!

[Former Member]

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[robert chamberlain]

I was under the impression that Sermos and Anderson Powerpole were the same. True? I was told some years ago that the Sermos had one or two different Amp rating available. Hobby shop is no help. I am going to guess that either is good for 30 Amps which is all I need right now. Any thoughts? Bob C

[Former Member]

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