The BSA A7-A10 Forum

Technical => Lucas, Electrical, Ignition => Topic started by: andy on 01.12. 2015 21:45

Title: Amp meter
Post by: andy on 01.12. 2015 21:45
Ohhh electrical gurus I've been scratching my head over this  and decided to put the question your way......right I've got around to the electrics on my project and decided to go down the 12v positive earth route what's the best reading on the amp meter
        8-0-8.        Or.      12-0-12
Many thanks.
Title: Re: Amp meter
Post by: duTch on 01.12. 2015 23:12

 Hiya Andy, I was dabbling with similar the other day, I've been using a 30-0-30 one that registers but only barely; I use imagination more....
 
 I conclude it doesn't matter much, but I figure the 8-0-8 will give a more accurate/readable reading, but depends on your loading I guess.

have a look at these links if you want;-

 http://www.a7a10.net/forum/index.php?topic=4183.msg28360#msg28360
and
http://www.a7a10.net/forum/index.php?topic=5035.msg34300#msg34300
and
http://www.a7a10.net/forum/index.php?topic=5035.msg74148#msg74148
 (http://www.a7a10.net/forum/index.php?topic=4183.msg28360#msg28360
and
http://www.a7a10.net/forum/index.php?topic=5035.msg34300#msg34300
and
http://www.a7a10.net/forum/index.php?topic=5035.msg74148#msg74148)

 
Title: Re: Amp meter
Post by: andy on 02.12. 2015 07:09
That's what I was guessing the higher the number the less it registered i.e. the needle didn't move much but I was wondering if the dynamo put out more than 8amps as I said I Don't know a lot about electricatry it's all voodoo and black magic lol I'm sort winging it as i go along cheers.
Title: Re: Amp meter
Post by: Klaus on 02.12. 2015 07:33
Hi Andy,

I have converted to 12 Volts and l recomment you a 12 Amp one.
Related with the output from the dyno 6 Volts 45 Watt a  8-0-8 is nearly scratch the end of the scale.  6V x 8 Amp= 48 Watt
This Type of dyno was a pre war construction.
ln The fiftys the rised up to 6 Volts 60 Watt, so you need the 12-0- 12 to read correct.  6V x 10 Amp= 60 Watt

I have an Alton Generator with 12 Volt 145 Watt,so I need the 12-0 12 one.

If you have an output less than 100 Watt at 12 Volt you can fit 8-0-8 one   12V x 8 Amp = 96 Watt

Hope this will help to find a decision.

Cheers Klaus


Title: Re: Amp meter
Post by: andy on 02.12. 2015 07:52
Yes it does thank you that was just what I was looking for.  *smile*
Title: Re: Amp meter
Post by: warmshed on 02.12. 2015 08:30
Just to confuse matters, why go for +ve earth?.  Most led and other electrical items are made for -ve earth  (+ve earth are available but higher cost and difficult to source away from home) as all new vehicles use this configuration, no advantage to go +ve earth. If using the dynamo before you connect a -ve earth regulator  just touch a wire from the positive side of the battery then flash it onto the F tag of the dynamo, just 2 seconds work.
Title: Re: Amp meter
Post by: a101960 on 02.12. 2015 08:59
Quote
Just to confuse matters, why go for +ve earth?.  Most led and other electrical items are made for -ve earth  (+ve earth are available but higher cost and difficult to source away from home) as all new vehicles use this configuration, no advantage to go +ve earth.
I agree