RCA 10.5 Connector for Battery Charger

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jkaness
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RCA 10.5 Connector for Battery Charger

Post by jkaness » Feb 12, 2018 12:51 pm

Has anyone found a source for the concentric connector, some call it an "RCA 10.5" that is similar to the audio RCA connector but with the outer shell of equal length to the center pin? My new 48-volt 20AH battery and 2A charger use this and they work fine. I have another charger with the Amphenol 3-pin connector and would like to change that connector, or make an adapter, but cannot find a source for the concentric male connector. My son's ebike was damaged in a fire and I rebuilt it- he's riding it again. Details posted at http://www.jimkaness.com/engineering/2018ebike.pdf .
RCA 10.5 Charger Connector.JPG
RCA 10.5 Charger Connector.JPG (15.19 KiB) Viewed 62 times
Last edited by jkaness on Feb 13, 2018 9:56 pm, edited 1 time in total.

rhizomatic
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Re: RCA 10.5 Connector for Battery Charger

Post by rhizomatic » Feb 12, 2018 3:59 pm

My charger, using this connector, just died and I have had a hell of a time sourcing one online. Worse, my 36v 12s lithium battery pack needs 43.5 volts and not the common 42 volts for a 10s lithium (if I understand the system correctly). Adapters I found for purchase online are of the audio RCA type. Stuck without my bike for most of a week now, I found wiring diagrams for adapting an XLR type connector to the audio-style RCA connector. I have ordered a charger that will deliver 43.5v and has the XLR. I am going to use my existing (dead) charger's connector for a DIY adapter. Wish me luck!

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jkaness
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Re: RCA 10.5 Connector for Battery Charger

Post by jkaness » Feb 12, 2018 4:38 pm

I am NOT a Lithium battery expert- I just buy them and use them! As I understand it there are several different lithium battery chemistries and they are "close but not the same" with regard to voltage. The only safe comment I can make is to use the charger that came with the battery. Many of these items come from China and the literature and specifications are hard to find. On two occasions I have emailed the manufacturer in China and received useful replies.

A useful article on lithium and other battery voltages is at http://batteryuniversity.com/learn/arti ... h_voltages .

I found and ordered an XLR to RCA adapter cable today at https://www.mycablemart.com/store/cart. ... ail&p=6380
When this adapter arrives I will need to verify the polarity of the voltage at the RCA end to be compatible with my battery (center pin positive). While I am capable of making up an adapter, I cannot buy the parts for the price of this adapter! If necessary I should be able to rewire the XLR to get what I need.

Good luck!

rhizomatic
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Re: RCA 10.5 Connector for Battery Charger

Post by rhizomatic » Feb 12, 2018 8:49 pm

Thanks for the tip! I just followed your lead and ordered the adapter. Much cheaper than ebikes.ca (a site that I love). So cheap, I just could not resist. I also might still do the rewire thing... here is one of the simple diagram sites I found. Easy stuff:
http://www.mediacollege.com/audio/conne ... rca-1.html

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Re: RCA 10.5 Connector for Battery Charger

Post by jkaness » Feb 13, 2018 9:17 am

Just one caution. I have in hand an ebike charger with an XLR connector. My charger (56.4 volts @ 2 amps) has the POSITIVE output on pin-1 and the NEGATIVE output on pin-2, measured by my voltmeter. Pin-3 is not used. This would be the REVERSE of what your diagram shows for audio use. Just make sure your RCA plug offers the correct polarity before connecting it to your battery! My battery wants the center pin to be POSITIVE. Please make sure what YOUR battery wants the center pin to be. You and I might have to rewire the XLR connector on the adapter cable we ordered, This is still cheaper and easier than buying separate parts!

Standards are great. But in this case we are using connectors, designed years ago for audio use, for battery charging.

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fechter
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Re: RCA 10.5 Connector for Battery Charger

Post by fechter » Feb 13, 2018 9:42 am

Just curious:
Was the fire caused by the bike?
"One test is worth a thousand opinions"

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eCue
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Re: RCA 10.5 Connector for Battery Charger

Post by eCue » Feb 13, 2018 9:49 am

I needed to charge hoverboard batteries with a charger so bought this connector

It can be found on eBay with this search term

Connector Adapter Plug Converter DC 5.5 x 2.5mm Female to XT60 male

You can find other connector versions under DC 5.5 x 2.5mm male (or female)

Image

:)
Solar charge station on wheels = distance not limited by the wall sockets :D

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jkaness
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Re: RCA 10.5 Connector for Battery Charger

Post by jkaness » Feb 13, 2018 10:02 am

Re: the fire. The battery (48 volts, 16 AH) was inside the trailer being charged when the fire broke out. The bike was outside leaning up against the trailer. No one saw what started the fire. My own best guess is that the battery started the fire but we will never know for sure. The AC wiring in that old trailer had been messed with over the years. The person who custom made our bike, and who custom made the original battery from individual cells, admitted to me that he had had other fires in some of his batteries and has now changed his approach to making batteries. That original battery had been in heavy use for some 18 months before the fire and we were comfortable with using it.

For what it's worth, the original battery used an XLR connector for charging. The charger I have in hand now was a spare for that. The original charger burned up in the fire.

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Re: RCA 10.5 Connector for Battery Charger

Post by jkaness » Feb 15, 2018 12:19 pm

Here is a drawing of the XLR to RCA audio cable (1) as purchased, and (2) as modified to provide positive polarity to the RCA center pin. The audio RCA male plug fits well (goes fully into the socket) into the battery's charger port and now the previous spare charger is available for use with the new battery. Tested and verified.

If desired, the RCA plug center pin could be cut off to be shorter, but it is not necessary here. Thus the need to purchase an "RCA 10.5" connector that started this thread is overtaken by events. :D
XLR RCA Adapter.png
XLR RCA Adapter.png (29.85 KiB) Viewed 17 times

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