Author Topic: JST connectors, changing polarity  (Read 1287 times)

deki

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JST connectors, changing polarity
« on: January 18, 2019, 02:59:27 AM »
My LIPO battery will not plug into the JST connector on the Current Ranger. The connectors look the same but mine is a little bit bigger. Also, thank goodness I checked and the polarity is swapped (red/black wires).

I see on the forum the there is a specific connector model number. This is the first time I have seen this.

Is there more to the story that I am missing?
« Last Edit: January 22, 2019, 09:48:44 AM by Felix »

Felix

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Re: It Appears Not All JST connectors are the same
« Reply #1 on: January 18, 2019, 09:31:52 AM »
The connector I specify is PH series.
The SMD JST socket on the CR board is this one.

This Digikey page also shows mating connectors that would be appropriate.
AFAIK all batteries at the usual online vendors use this connector (sparkfun, adafruit, etc).
But I will say that if you search for batteries on ebay/aliexpress, you should be able to find them with PH 2.0 pitch connector. If polarity is wrong, you can easily pull and swap the connectors in the connector housing.

I also offer a compatible JST mating connector that you can solder to any battery (even AA/AAA pack if you want to use that).



This is the JST receptacle used on the CRanger PCB:



« Last Edit: January 18, 2019, 09:37:56 AM by Felix »

lottabull

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Re: It Appears Not All JST connectors are the same
« Reply #2 on: January 18, 2019, 04:46:24 PM »
The SparkFun battery I got needed the vertical fin on the top sanded down a little to go in easily.

If the connector is a tight fit the force required to remove it makes removal hazardous to nearby components.

Felix

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Re: It Appears Not All JST connectors are the same
« Reply #3 on: January 18, 2019, 05:23:05 PM »
If the connector is a tight fit the force required to remove it makes removal hazardous to nearby components.
That's unfortunately quite common depending on vendors of the different mating connectors.

deki

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Re: It Appears Not All JST connectors are the same
« Reply #4 on: January 19, 2019, 07:02:12 PM »
Could not find correct batteries on the "Shop" tab so I ordered them from Amazon. The polarity on the Current Ranger, the MightyHat and MightyBoost boards do not match the Amazon battery; Thank goodness I have spare JST cables with the correct polarity. BTW, the Amazon battery plugs into the MightyHat and MightyBoost (did not seat the pins) but not the CurrentRanger connectors. But wrong polarity anyway I need to change cables on my batteries.

Hope this post helps somebody else.

deki

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Re: It Appears Not All JST connectors are the same
« Reply #5 on: January 19, 2019, 07:15:27 PM »
BTW, I had no luck swapping the pins on the Amazon battery, little tab would not pull out. So cut the wires on the battery and soldered in the new cable so they were the same length. I read that there was a noise problem in another post from battery leads. Still 50 mm in length.

Felix

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Re: It Appears Not All JST connectors are the same
« Reply #6 on: January 20, 2019, 11:12:27 AM »
As a rule of thumb, keeping wires short, that attach to any electronics, is a good idea.
The battery wires need not be long in this case. Typically these batteries do not have long leads anyway, so I would not go through the effort to trim them even shorter, without a good reason (ie you notice a significant difference).

deki

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Re: It Appears Not All JST connectors are the same
« Reply #7 on: January 22, 2019, 01:19:38 AM »
Update. I figured out how to change the polarity on the JST connector on my Amazon LIPO battery. Remember the polarity was rolled. I took my tiniest screw driver and a magnifying glass and found out all one has to do is lift up ever so slightly on the plastic retainer for the pin then pull it out. Then I rolled the polarity. Works great.   

alexsh1

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Re: JST connectors, changing polarity
« Reply #8 on: February 04, 2019, 02:20:46 PM »
Sparkfun battery works fine. The connector is tight, but I never take the battery out so does not matter for me.

BTW, this is how I damaged my C.H.I.P. by plugging the battery with the wrong polarity, but the same connector.
One would have thought that there is a protection....but no!

jdheinzmann

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Re: JST connectors, changing polarity
« Reply #9 on: May 09, 2020, 10:37:32 PM »
I too am finding the key slot on the connector on the Moteino M0 is too tight for all the Li-Po batteries and battery cables I have bought from SparkFun.  It would be so nice if the connector on the Moteino M0 was more compatible with the ones on these batteries.  Until they are, I will be needing to shave down the tabs for each remote setup I build.  Unless there is a source of batteries with a more compatible connector.  Any suggestions?

Felix

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Re: JST connectors, changing polarity
« Reply #10 on: May 10, 2020, 03:47:57 PM »
Yeah I have noticed.  :-\
I can say this - the JST battery connectors I mount on all my products are direct import from JST Japan. I bet the cheapo lipos mating connectors are not OEM connectors.
FWIW - I have also seen connectors that are very loose and cause intermittent battery connections. So IMO a tighter fit is better than a loose one, save for the effort to make it fit.