Battery connectors

[leccyflyer]

Posted by Erfolg on 31/07/2020 10:39:58:

I do not recognise the split tube that has been mentioned on the XT connectors. I have checked the connectors i presently have. They all are off the solid conductor stock material. The male plug is slit, the female a unbroken tube.

I have had at least two male connectors in the past that were male 4mm sprung bullet connectors in the past. Why I cut the conductors out of the body, is now lost in the mist of time. These in principal could be better.

What particularly spurred me into a change to XT is that I consume quite a few Lipo batteries, say in a 12 month period. I was concerned with respect to the safety issues when cutting off a XT plug on the Lipo, even with a strict sequence of operations. So changing one ESC connector was safer.

I have always found the soldering of Deans plugs a bit of an issue, using a multi-hand (helping hand) type crocodile clip base. Invariably the Lipo had to be packed up, this was to remove any strain on the crocodile clip, the Deans body also not the easiest to hold securely.

Bullet connectors are easy, drill a hole in a piece of balsa (scrap), push the connector into the hole, place upright on the bench (or what ever), Using the multi-hand insert the wire conductor (vertically) into the solder socket, then solder the joint (having pre tinned).

I do XT connectors in a similar way, although now, I have a piece of balsa, with a few restraints Cyno on, which hold the connector.

I see two significant advantages immediately, I now change connectors less frequently, more so as time passes. Perhaps IMO the process has far less hazards and exhibits increased safety than working on a live Lipo.

As to the functionality of the plugs, who other than those with an axe to grind has a operational and functional issue with them? Generally not users.

When bullets were the common method, there were instances that the sprung cage was not of the quality in the longer term that ensured functionality. My main concern having witnessed some one pug two batteries together, that a strict protocol was required, then I have seen a unshielded male connector make contact with the case of a metal box (there was no consequence).

In short we can all point at supposed failings of any piece of equipment. Much come down to both safety and convenance.

Edited By Erfolg on 31/07/2020 10:40:50

Edited By Erfolg on 31/07/2020 10:42:03

Couple of points.

Taking care with changing connectors on live lipos ought to really be second nature but conducted thoughtfully and a set procedure helps. Deal with one wire at a time, completely insulate or isolate the connector after it is put on (I fold the wire back against the lipo case and secure with a rubber band whilst working with the other connector). Cutting through both wires at the same time, leaving bare ends floating in the breeze, not insulating the connectors correctly as they are made are all to be avoided. It is a matter of taking appropriate care on the bench.

Likewise, with careful selection of lead length and connector positioning it is perfectly feasible to make polarised 4mm bullet connector set ups that cannot possiblly touch each other, or be able to connect the battery pack to itself . a single lap of insulating tape, or even heatshrink if organised enough to preplan it;s installation, gives further peace of mind in preventing inadvertent shorts.

For my own system I employ colour coded lenghts of blue Sullivan snake out to cover the positive male pin on the battery at all times, except when the connection is actually being made. These are blue for discharged (or storage voltage, or used) and replaced by green when the pack comes off the charger, thus given an instant indication of the status of the battery pack and also preventing the sort of positive pin contacting a metal box scenario described.

I have a question for those using XT30s XT60s and XT90s. If using a UBEC or SBEC, how do you go about making the connections to the battery plug? On the 4mm bullets I tend to solder the thin UBC wires to the tinned ends of the ESC power wires, secure with heatshrink then solder both wires onto the 4mm male and female connectors. My understanding of the plastic connector shrouds is that the wire is inserted through the shroud then, with the connector added the wire needs to be pulled back firmly into the shroud, to seat with a click? Can you do that with a UBEC wire connected?

[Bob Cotsford]

You're thinking of the EC series connectors where they're pulled/pushed back into the moulding. XT series have fixed connectors with the end to be soldered permanently exposed and needing to be covered with heat shrink sleeves.

[Andy48]

Posted by leccyflyer on 31/07/2020 16:30:57:

For my own system I employ colour coded lenghts of blue Sullivan snake out to cover the positive male pin on the battery at all times, except when the connection is actually being made. These are blue for discharged (or storage voltage, or used) and replaced by green when the pack comes off the charger, thus given an instant indication of the status of the battery pack and also preventing the sort of positive pin contacting a metal box scenario described.

[leccyflyer]

Thanks Bob -you're correct I was thinking the XTs were similar to the ECs. I have a load of them that I've cut off battery packs, I'll strip one down and take a closer look.

[Trevor Crook]

Although I haven't used them, the batch of XT90s I bought came with moulded shrouds to clip over the wires once soldered. If I were attaching ubec wires I would leave the shrouds off and use heatshrink as described by leccyflier above.

I also use the rubbery covers pictured above on my XT60s - a real boon for indicating whether I have used the battery or not.

[Mike T]

They all have their faults and none of them are 'fit and forget'.

As RC2 mentioned above, I've had XT60's go 'slack' on me and opened up the (non-springy plated brass) pins to improve the grip. Best course is to lop it off and solder on a fresh one.

4mm bullets are annoyingly bulky and the male on the ESC goes slack after a while - again lop and replace.

Even with Deans (the original plugs are superb) I've known the springs de-temper and/or snap and require replacement.

Charge state? Rubber band around pack and leads = charged and ready. No band = used, charge required.

[John Lee]

Posted by Trevor Crook on 31/07/2020 19:37:41:

Although I haven't used them, the batch of XT90s I bought came with moulded shrouds to clip over the wires once soldered. If I were attaching ubec wires I would leave the shrouds off and use heatshrink as described by leccyflier above.

You may not need to leave off the shroud, here's one of my XT60 connectors with 12AWG main leads and addition sensor wires. The extra wires fitted though without trouble but if the won't go directly you can file a notch.

[Erfolg]

IMO at present it is a No Brainer. Using anything other than XT plugs and sockets is antediluvian (what ever that means).

The vast majority of Lipos come with XT plugs. Once your ESC is fitted with a XT, all is happiness. This used to be the situation with Deans.

Deans shot themselves in the foot when they got arsenal (or something similar) with those who were not prepared to pay the royalty/license fee for the Deans style system (which i once read was not trivial). Some one came up with a design which at least matched the Deans in both functionality and safety (IMO surpassing the Deans). Is there any restriction on using the XT design and specs?

As for UBECs, I have only wired in one, in my case I spiced in the UBEC wire at a convenient point then Heat shrunk the junction as i do with my my power "Y" leads. I did see one installation where the plug carried extra connectors for the leads. Again IMO not a great place to attach such flimsy bits of wire.

What is driving the use of XT plugs is the fact that manufacturers choose to use the plug on their Lipos or most do, it works fine, also, that me, a Joe Bloggs  can buy the units at sensible prices at almost every street corner. Just like the UK 30A domestic plug. there is no need to advertise or any other ploy, it sells itself.

 

Edited By Erfolg on 31/07/2020 20:13:32

[leccyflyer]

Posted by Erfolg on 31/07/2020 20:10:50:

IMO at present it is a No Brainer. Using anything other than XT plugs and sockets is antediluvian (what ever that means).

The vast majority of Lipos come with XT plugs. Once your ESC is fitted with a XT, all is happiness. This used to be the situation with Deans.

Deans shot themselves in the foot when they got arsenal (or something similar) with those who were not prepared to pay the royalty/license fee for the Deans style system (which i once read was not trivial). Some one came up with a design which at least matched the Deans in both functionality and safety (IMO surpassing the Deans). Is there any restriction on using the XT design and specs?

As for UBECs, I have only wired in one, in my case I spiced in the UBEC wire at a convenient point then Heat shrunk the junction as i do with my my power "Y" leads. I did see one installation where the plug carried extra connectors for the leads. Again IMO not a great place to attach such flimsy bits of wire.

What is driving the use of XT plugs is the fact that manufacturers choose to use the plug on their Lipos or most do, it works fine, also, that me, a Joe Bloggs can buy the units at sensible prices at almost every street corner. Just like the UK 30A domestic plug. there is no need to advertise or any other ploy, it sells itself.

 

Edited By Erfolg on 31/07/2020 20:13:32

 

 

IMO it is horse for courses and no one connector is the only choice to be made in all situations. The modeller should use the connector type that works for themselves, in their own models and, again IMO< without changing over dozens of connectors every time a new one comes out - especially when, as is so often the case, the connectors that they are already using are working perfectly well. Again the exception would be those terrible high resistance points of failure that are the old Tamiya connectors. The argument that there is a de facto standard plug is flawed - there was a time when battery packs came with those Tamiya/Molex connectors as standard and they were awful, so being used by multiple vendors as the default is no guarantee of quality.If there was a standard plug I wouldn;t have a drawer of at least three different plug types supplied on manufactured battery packs.

Claiming that using anything other than connector Type X fails to recognise the diversity of uses which the modeller is going to put battery packs to. The example of the 6mm bullets in high current applications for very thick gauge wire is a case in point. Thinking on I do actually have a few packs on RTF models which use the JST connector for the small lipos and I haven't changed those out for 4mm "gold" bullets either. They are flown so infrequently I haven;t bothered to change them out - but equally I would never criticise anyone for using those small connectors on that size of model. In fact I would greatly prefer if those were used rather than the horrible connectors built in to the 70-100mah 1s lipo batteries in UMX models.

Edited By leccyflyer on 31/07/2020 20:33:53

[Bruce Collinson]

Having set off 4 yrs ago with Deans, I switched the whole fleet to XT 60 a year ago after getting fed up trying to solder Deans. Also, it seemed to me there were a lot of inferior Deans copies about. Since acquiring some 6S planes I have stuck to XT 90s but always try to specify Amass anti spark, with shrouds. They are so much easier to solder, even for me.

The major problem I have with the 90s especially is getting them apart. I have a serious aversion to pulling on the cables. I have tried graphite as a lubricant and also polishing the male sockets but feel sure I’ve missed something. Ideas?

BTC

[john davidson 1]

No one has answered the question about small models, I believe JSTs are still widely fitted as original for up to 1000mh 2 to 3 cell .batteries with the advantage of small size which can be important in a cramped fuse, they seem to cope with currents well above their rating too. I changed to XTs for larger modeels when i had unreliable contacts with a deans and I also found them hard to disconnect

[leccyflyer]

For most of my smaller models, typically usung 3s1p1300mah lipos I use the 4mm bullets, additional weight is minimal. For a few, rarely flow RTFs I have 2s1p850 and 500mah lipos and haven;t bothered to change out the JSTs, which seem perfectly adequate for those smaller models. It would be very strange to fit XT60s to those models -hence my comments regarding the statement that they are the one true divinely annointed connector ..

[Former Member]

[This posting has been removed]

[Erfolg]

JD, a confession I have a few packs/models with JST connectors.

Again the Lipo (s) came with the connectors, so why make life more difficult by rewiring the battery? Of hand I do no know which models have them, other than I must not be playing much with them.

Again, they do the job, with small currents, why fuss?

The only down side it is a case of making up a charging lead, for the JST.

At present one of my chargers still has Deans on the power leads, which mostly has a conversion plug in the output. More of a nuisance is my Watt meter having two Deans on it. I am often tempted to change the plugs. I do not, as often there are consequences which I did not recognise, then need to make another set of conversion plugs..

Like many Xt users, I have no issues with many of the plugs, other than most are now pretty much museum cases, but not all.

[Richard Clark 2]

Kontronik (who I think is the best motor and ESC manufacturer of all) use silver plated beryllium connectors.

Silver (which is more conductive than gold) tarnishes but it doesn't matter as the tarnish is very thin and connectors you slide on and off as opposed to 'pressed' ones such as relay contacts are self-cleaning.

UK 'elf and safety' would not like beryllium but who cares?

[leccyflyer]

IRC the Anderson Power Poles (which were the first connectors I tried way back in the day) also have silver plated contacts.

For the "gold" connectors, my understanding - and I've done some investigation myself many years ago -is that the extremely thin gold coating is put on the connectors due to the better mating and self-cleaning nature of gold-to-gold contacts, which benefit from gold not tarnishing. The base metal of the connectors is essentially brass, with copper, nickel and zinc in the make up, which would otherwise tarnish. After many hundreds of insertions I don;t recall seeing any of my connectors worn back to the bare brass, that flashy gold coating, though thin, seems to self repair with use.

The issues described earlier in the thread with the basket on the male bullet connectors losing their springiness over time, or even due to excess heat during lengthy soldering with too small an iron, were discussed at length in extended threads on a number of fora.

[perttime]

Posted by Steve J on 31/07/2020 22:12:33:

Posted by john davidson 1 on 31/07/2020 21:51:12:

No one has answered the question about small models...

Two of us have mentioned XT30's. The Deans micro is another nice little connector.

My local shop has small packs with JST connectors. Sounds like I'd be better off changing those over to XT30.

Edited By perttime on 01/08/2020 09:28:19