The BSA A7-A10 Forum

Technical (Descriptive Topic Titles - Stay on Topic) => Lucas, Ignition, Charging, Electrical => Topic started by: Davmacb on 08.08. 2011 22:22

Title: non charging 12v conversion
Post by: Davmacb on 08.08. 2011 22:22
Have recently converted my A7SS to 12v and the starting and running is fine but I can't get the bike to charge the battery.  I have completely rewired the bike from scratch.  Fitted a 12v armature and field coil to the dynamo.  Bought two new batteries (one gel and one standard).  Fitted an new DVR2 regulator and cut-out and still it won't charge.  The ammeter (new) shows a discharge when I turn the lights on but doesn't move even a fraction when I rev up.  The dynamo is definately giving out current as I have tested it and it lights a headlanp bulb when wired directly.  I have all the circuits from the battery and DVR2 protected with fuses which are not blowing.  Any suggestions gratefully recieved.
Title: Re: non charging 12v conversion
Post by: trevinoz on 08.08. 2011 22:38
If you have done the first test at the dynamo by bridging "D" & "F" and have the correct voltage, have you also established whether the polarity is correct?

  Trev.
Title: Re: non charging 12v conversion
Post by: A10Boy on 09.08. 2011 11:55
Quote
Fitted a 12v armature and field coil to the dynamo

Did you polarise it afterwards?  Flash a wire from whichever battery terminal is live [eg not earth] to the dynamo field terminal. This should be negative, as i believe the DVR2 works Positive earth only so make sure thats how you set the dynamo and battery up. If you connect some electronic regulators the wrong way they can be damaged.

HTH
Title: Re: non charging 12v conversion
Post by: Davmacb on 10.08. 2011 08:15
Thanks Andy.  Yes I've tried the flashing and also fitted a fuse (which doesn't blow) from the DVR2 A (output) terminal as per the instructions.  Still nothing.  I've now contacted an auto electrician as a last resort so I'll post the mystery results once he has figured it out.
Title: Re: non charging 12v conversion
Post by: old53 on 10.08. 2011 13:51
I have a similar problem but with 6v system maybe related. Ive fitted an electronic Wassel regulator to my A10 followed all instructions has correct polarity and have had dyno motoring like electric engine on bench as specified in instruction  but my amp meter shows discharge when my lights are on. The original regulator was wired to one side of the amp meter but the instruction for the electronic reg goes straight to battery. Is it possible that it is charging the battery but showing discharge at amp meter is it is in series with light circuit? I hope this makes sense.
Title: Re: non charging 12v conversion
Post by: bsa-bill on 10.08. 2011 15:41
The three wires from the regulator (original or new solid state type) two from the dynamo, one to earth and the other to the ammeter, and this one to the ammeter goes to the opposite side of the ammeter than the wire from the battery.
Title: Re: non charging 12v conversion
Post by: old53 on 12.08. 2011 09:29
Thanks Bill- attached is the diagram I received with regulator. Have I got this right the black wire going to Battery in diagram can go to the load side of amp meter cheers
Title: Re: non charging 12v conversion
Post by: bsa-bill on 12.08. 2011 10:42
Hi - yes, I should have posted this pic as well although I think it's on here somewhere
Title: Re: non charging 12v conversion
Post by: Stu55Flash on 05.09. 2011 22:29
Try connecting a meter across the battery and take a note of the voltage reading with and without the engine running and when revving up.  You could also connect an ammeter in series and see if its charging. Your ammeter on the bike maybe a bit one sided - most are made in China and will not be calibrated. They would show a flick with the old on off switch regulator but with the electronic system will be trickle charging and not easy to see.

Stu
Title: Re: non charging 12v conversion
Post by: BSA_54A10 on 06.09. 2011 11:49
Also remember that the regulator will not allow the generator to generate till it decided that the battery needs it so if your battery is fully charged then the generator will not generate.
Title: Re: non charging 12v conversion
Post by: iansoady on 06.09. 2011 12:32
There's normally a small charge going into the battery even when it's fully charged.

Depending on the regulator type (some need the battery connected) you could disconnect the black wire from the battery then put a voltmeter between the regulator black wire and earth. You should then see either around 7.2V (6V system) or 14.4V (12V system).