How to charge a battery
It is possible to wire up the std 12volt ac regulator to a mini bridge rectifier wired in paralell, to then charge a battery which you can then use for your dc supply, I have done this on about 30 or more Lambrettas and a couple of small frame vespas. Using a mini bridge rectifier, the ac connections on the rectifier (mini bridge) are not used.
The negative connection of the mini bridge is wired to the regulator (from the same connection that feeds the loom with power).
The positive from the mini bridge terminal is connected to the battery's positive connection, then the battery's negative is connected through a fuse to earth.
This will give the battery a charging current of about 2 amp hour, under normal use. From what would be termed a "half wave rectified supply". I use this set up as its very cheep reliable and simple, as the ac is already regulated to about 14.6 volts all thats needed is a circuit that turns the ac supply into a dc current, which the rectifier (mini bridge rectifier) does.
Mini bridge rectifiers are available from about £5, and claim to handle current up 35 amps. and up to 400 volts. signified by markings on the side 35/400 these are available from Maplins, and this is the one I use and have used on my GP for the last 11 years, I must admit I have managed to boil the battery when on a Euro rally due to too many revs for too long, over charging the battery. This is not the fault of the rectifier but more the ac regulator supplying too high a voltage at prolonged high revs. I also run this system on my SX and the battery is now 7 years old and still working, but this is a 12volt 7amp sealed battery, much better quality than the Lambretta Item. I hope this little bit of info is of some help to anyone looking for some dc power from standard 12 volt ac system as fitted to all Indian electronic SIL systems....
The negative connection of the mini bridge is wired to the regulator (from the same connection that feeds the loom with power).
The positive from the mini bridge terminal is connected to the battery's positive connection, then the battery's negative is connected through a fuse to earth.
This will give the battery a charging current of about 2 amp hour, under normal use. From what would be termed a "half wave rectified supply". I use this set up as its very cheep reliable and simple, as the ac is already regulated to about 14.6 volts all thats needed is a circuit that turns the ac supply into a dc current, which the rectifier (mini bridge rectifier) does.
Mini bridge rectifiers are available from about £5, and claim to handle current up 35 amps. and up to 400 volts. signified by markings on the side 35/400 these are available from Maplins, and this is the one I use and have used on my GP for the last 11 years, I must admit I have managed to boil the battery when on a Euro rally due to too many revs for too long, over charging the battery. This is not the fault of the rectifier but more the ac regulator supplying too high a voltage at prolonged high revs. I also run this system on my SX and the battery is now 7 years old and still working, but this is a 12volt 7amp sealed battery, much better quality than the Lambretta Item. I hope this little bit of info is of some help to anyone looking for some dc power from standard 12 volt ac system as fitted to all Indian electronic SIL systems....
I think you have the polarity wrong as the only way current would flow is back to the regulator.J1MS wrote: The negative connection of the mini bridge is wired to the regulator (from the same connection that feeds the loom with power).
The positive from the mini bridge terminal is connected to the battery's positive connection, then the battery's negative is connected through a fuse to earth.
The vespa reg with the one extra terminal "B+" shouldn't need a diode fitted as there is one in the regulator giving the half wave output. The more complicated ones for example the AF DC type with the "C" connection do need the switch as these have a feedback circuit controlling the rate of charge.
Steady on, i did say simple instructions. I'm totally lost now. Any chance of a diagram? Also the regulator i have is the small Variotronic type, Remember now, simple 
Sorry didnt mean to confuse any one, just thought it relevent and posted it here. Polarity is right, as the configuration of the four diodes in the rectifier allows current to flow, from the negative terminal to the positive terminal and then into the positive of the battery as when you use a battery charger you wouldnt connect the red /positive, to the black/negative, if it was wired contrary it would not work. This is a half wave rectification and it really does work, also costs the least of all available conversions. I used to rewire alot of stators and honestly do understand this subject with an indepth knowledge so much so, that when I get stuck I usually ask myself the questions...J1MS wrote: I hope this little bit of info is of some help to anyone looking for some dc power from standard 12 volt ac system as fitted to all Indian electronic SIL systems....
Yes, sorry JIMS you are correct, I was thinking of a single diode. 
firekdp wrote:Yes, sorry JIMS you are correct, I was thinking of a single diode.
My fault and once again, sorry. I never fully explained myself clearly enough, but if anyone now gets it. it may be of some help to someone.....All the best
Thackers, is it the scootrs rectifier?
