Dirty Connectors

[scallybert]

Anyone had any problems with dirty connectors - particularly JST power connectors ?

If so, what were:

* The symptoms ?

* The cure ?

* Any suspected cause ?

[Andy from Sandy]

The JST connectors I have seen are the tinned, bright silver. I have not seen gold plated ones. If you are disconnecting the connector in order to charge the battery then you are continually wiping it and therefore it should be self cleaning. The only way it is going to get dirty or have an oxide form on the contacting surfaces is if you don't use it for some time. All you should need to do is swish it around in some contact cleaner and then plug and un-plug it a few times and it will become clean again.

A symptom of dirty contacts depending on current flow will be that they heat up.

As the contact will be high resistance your battery monitor will read low. Your charger may report the cell voltage incorrectly and may not charge it.

[scallybert]

That's all in line with what I'd expect.

I've seen the motor consistently partially spin up, then spin down. AR6200 indicates a power failure. Tried loads of things. Then tried contact cleaner on JSTs. Problem goes away.

Suddenly (after maybe an hours flying time) that problem, or power failures in flight, re-appears. Cleaning conectors seems to help again.

Connectors aren't hot though.

Symptoms aren't at all conlcusive here, but cleaning connectors is only thing that's made a difference. (Inc (pretty much) complete electrics swap !!!)

Hence my asking if other have had problems with these.

TBH, I think I'm close to being over current, but this is a stock rotored/geared/motored/ESCed/etc EP100 SE Pro that's got a pretty high head speed.

[Andy from Sandy]

I would not use the jst connector for the main flight battery to a motor regardless of how much current you think the motor needs. Replace it with a proper connector rated at what the battery can supply. Typically you should either use Deans or power poles or the type you see used for brushless motors to esc.

[AndyThilo]

Yep deans all the way, make sure you buy genuine ones though, the cheap copies are crap and don't make a good connection, plus their not very compatible with genuine deans (fit and connection).

[Sao]

Cut 'em off and bin them
JST's are power sapping pieces of shit second only to tamiya connectors in the league of shit battery connections.

Fit some Micro Deans to replace them

[scallybert]

Cut 'em off and bin them
JST's are power sapping pieces of shit second only to tamiya connectors in the league of shit battery connections.

Fit some Micro Deans to replace them

I think I'm getting a clear message here...

Do you have a URL for some 'Micro Deans', and do the plugs and sockets come separately ?

[scallybert]

Do you have a URL for some 'Micro Deans', and do the plugs and sockets come separately ?

I've ordered these http://www.aurorra.co.uk/shop/produc...roductid=16236 - which are hopefully what was meant. They look ok, anyway.

[Sao]

Those are the kiddies

They are not plug and socket (well they are but there is a plug and a socket on each half), they are polarised though so you cant plug 'em in backwards

[scallybert]

Those are the kiddies

Cool.

They are not plug and socket (well they are but there is a plug and a socket on each half), they are polarised though so you cant plug 'em in backwards

Yes, I eventually found a picture big enough so I could figure out that was how they worked.

Behaviour of the JSTs plus some Iso-propyl alcohol & elbow grease today, has left me reasonably confident they were the root of this problem. So hopefully these conectors will keep the EP100 SE Pro consistently in the air.

[AndyThilo]

Only use micro deans on 350 micro helis, I wouldn't use them on a 400/450 heli.

[scallybert]

Only use micro deans on 350 micro helis, I wouldn't use them on a 400/450 heli.

This is a 100, so hopefully should be ok.