The BSA A7-A10 Forum

Technical (Descriptive Topic Titles - Stay on Topic) => Lucas, Ignition, Charging, Electrical => Topic started by: rustydusty on 21.03. 2023 22:26

Title: Positive ground…
Post by: rustydusty on 21.03. 2023 22:26
I’m installing a new 6v battery in my A10. The battery is currently hard wired with a fuse on the + side. Will this work as a fuse on the ground side or should I cut off and install it on the negative (hot) side…
Title: Re: Positive ground…
Post by: Triton Thrasher on 21.03. 2023 23:12
It’s better to have the main fuse on the ground/earth/return side.
Title: Re: Positive ground…
Post by: groily on 22.03. 2023 06:27
It’s better to have the main fuse on the ground/earth/return side.
Is where I put mine too.
Although much of the literature - eg Dr James Smith's 'Classic Motorcycle Electrical Manual' - goes for the live side.
Probably the most important thing is that, where the horn and/or  brakelight are taken direct from the battery, they are covered. Often they aren't in live side fuse installations. As they are among the commonest sources of short circuits  . . . .
Title: Re: Positive ground…
Post by: Greybeard on 22.03. 2023 09:21
I happened to buy a generic double fuse box so both + and - are fused.
Title: Re: Positive ground…
Post by: Triton Thrasher on 22.03. 2023 12:47
It’s better to have the main fuse on the ground/earth/return side.
Is where I put mine too.
Although much of the literature - eg Dr James Smith's 'Classic Motorcycle Electrical Manual' - goes for the live side.
Probably the most important thing is that, where the horn and/or  brakelight are taken direct from the battery, they are covered. Often they aren't in live side fuse installations. As they are among the commonest sources of short circuits  . . . .

Fuse on the return side also mitigates the sort of short circuit that clumsy mechanics (blush!) cause by touching the battery live terminal and the frame, with a spanner.
Title: Re: Positive ground…
Post by: rustydusty on 22.03. 2023 14:29
I happened to buy a generic double fuse box so both + and - are fused.

I already have the hot (negative) side fused, so that would work out fine…
Title: Re: Positive ground…
Post by: rustydusty on 22.03. 2023 23:30
So I added the supplied electrolyte to the battery, put it on my “intelligent” charger. It showed “charge” for an hour or so, then indicated “bad”…

I don’t get it. This battery is new.
When I said “new, I forgot to mention that it has been sitting in the box, on my shelf for 20+ years…

Ordered a new one, hopefully it hasn’t been sitting on their shelf for 20 years…
Title: Re: Positive ground…
Post by: muskrat on 22.03. 2023 23:42
G'day Rusty.
You might be able to resurrect it by hooking it up to a good battery and charging through that. It worked for me once or twice.
Cheers
Title: Re: Positive ground…
Post by: Rex on 23.03. 2023 09:06
Or by hooking up an old style "non-intelligent" battery charger in parallel with it and keeping both connected until the "intelligent" charger senses the battery has reached a certain voltage. It's usually very quick.
Title: Re: Positive ground…
Post by: RDfella on 23.03. 2023 11:11
I have a couple of 'intelligent' chargers and often have to question their IQ. As Rex has suggested, reverting to a 'dumbo' charger is usually more effective. In fact the only time I still use one of the 'intelligent' ones (have thrown a couple away over the years due to charging fussiness) is when I want to charge a small (eg motorcycle 6v) battery and need to leave it on for an unknown period, when a conventional one might cook it.
Title: Re: Positive ground…
Post by: rustydusty on 23.03. 2023 12:14
Thanks guys, I will give that a try…
Title: Re: Positive ground…
Post by: Greybeard on 23.03. 2023 15:06
As other have said, so called 'intelligent' chargers are stoopid. If the battery has no voltage they will not come out to play. I bought an old style charger from FaceAche Market Place. I suggest you do something similar. 👍
Title: Re: Positive ground…
Post by: rustydusty on 23.03. 2023 15:23
Well I hooked up my “stupid” charger in series with my charger that claimed to be smart, and after an hour of charging, came up “bad” again. My voltmeter says 6 volts but that is probably a “surface charge”. I have a “load tester” but it’s not designed to work with a small 6 volt battery.
No problem, I have a new battery coming in the mail in a couple of days…
Title: Re: Positive ground…
Post by: Greybeard on 23.03. 2023 15:51
Storing an unused lead-acid battery dry should not cause it to deteriorate.

Have you been able to try a traditional transformer+rectifier charger?
Title: Re: Positive ground…
Post by: Rex on 23.03. 2023 17:22
Well I hooked up my “stupid” charger in series with my charger that claimed to be smart,

Parallel, not series.
In series the clever charger will just think it's a 12V battery with three duff cells.
Title: Re: Positive ground…
Post by: rustydusty on 23.03. 2023 17:54
Sorry, I meant parallel. And the charger I used with it is probably 45 years old. ( not smart at all…)
Title: Re: Positive ground…
Post by: rustydusty on 23.03. 2023 23:14
Storing an unused lead-acid battery dry should not cause it to deteriorate.

Have you been able to try a traditional transformer+rectifier charger?
I totally agree. The battery and electrolyte were still sealed in its original box. Problem is, the only traditional charger I have is indeed 45 years old and a 1 amp trickle/motorcycle system that I haven’t used in probably 30 years. Everything else I have is 12v only…
Title: Re: Positive ground…
Post by: Colsbeeza on 23.03. 2023 23:20
Hi Rusty,
I had the same experience a few years ago. I had a new 6V battery stored dry for about 25 years with acid in a separate bottle. I added the acid and stuck it on a conventional charger and nothing happened. It would not take a charge. I got a new battery.
Col
Title: Re: Positive ground…
Post by: rustydusty on 01.04. 2023 13:24
Okay then…


Seems like my stupid “smart charger” is smarter than me…


I received the new battery, tried to charge it, or “kick start” it with three different chargers and it still came up “bad”.
Finally, I looking really closely at the charger display, and noticed a tiny little “icon” that said: 12v. I pushed the mode button a few times and sure enough, there was a 6v mode. I thought the charger was smart enough to detect was type of battery it was connected to and would set itself accordingly. Well, it quickly charged my battery to “full”, I then hooked up my original battery and shortly had that one fully charged too! I guess I have a spare now…
Title: Re: Positive ground…
Post by: Greybeard on 01.04. 2023 13:35
Not so smart are they!