Split charge for dynamo?

Given the output of the Lucas C40 being about 25 amps at best, I can't see why you'd want to. In theory there's no reason why you can't, but if you have that much potential load on the vehicle in the first place you really should be considering an Alternator to keep up with the vehicle and charging load in the first place.

Alex

So Alex was, like

I know the dynamo output is low (I thought it was 20A), but I have a good second battery hanging about (another story) and figured it might be a good idea to add it to the system. Recently, a lot of my driving has been with lights, wipers and blower on, and I reckoned the extra capacity would be useful. An alternator (as well as some decent lighting) is on my shopping list, but as the spare battery is already under the passenger seat I thought it might be a useful addition for the sake of an hour's work.

Cheers

My 2a has a second battery connected in parallel on a dynamo system. The regulator has separate regulators for the two batteries so a split charge isn't necessary. I thought that was pretty standard for Lucas regulators ...

Regards Steve G

Richard Brookman wrote:

Depends if you've got the C39 or C40 fitted. The C39 is about 18 amps, the C40 is about 25 (IIRC). Certainly if you want to go ahead with it, then by all means, personally I'd just fit an alternator instead, I already have a 110Ah battery under the bonnet anyway, which is a vast improvement on the original spec battery.

Alex

So SteveG

If you are thinking the extra battery will help with the extra load while driving - it won't. All it will do is store extra energy, not make it. If your battery is not keeping charged then fitting a second battery will simply mean you have two batteries not keeping charged. In fact, the situation may be worse, due to a slight loss of efficiency with a split charging situation. The only reason for a split charge system with two batteries is where you are using power while NOT driving (such as winch, work lights, refrigerator etc.), so that one battery can be kept for starting. A major problem with a dynamo as opposed to an alternator is not the lower rated output, but the fact that the dynamo outputs its rated power a lot less of the time, as it has to be run at a lower speed relative to the crankshaft (The windings on the alternator armature are circumferential which means they are pretty much immune to centrifugal force, whereas the windings on the dynamo armature include sections that are axial and rely on varnish to keep them in place - alternators are geared to run at about twice the speed of dynamos). JD

Richard,

Sorry I haven't reponded before ... been a bit busy ;-)

I'll take a look at the circuit diagrams I inherited with the LR and see what I come up with. I'm pretty certain that in amongst the box of bits I got there's a spare regulator which was replaced but later found to be good. Give me a couple of days ...

Regards Steve G

Richard Brookman wrote:

So SteveG