series -paralell switch

[quote="Tim Matthews"]My generator seems to be working fine at 12 volts ,but I have a 24 volt starter .
Does anyone have a recomendation on a series paralell switch? Thanks Tim[/quote]
This is probably something that you already know but a lot of the trucks in the old days used them with two or four twelve volt batteries.The switch should not be hard to find.Ron G

Hook the batteries in series to get the 24 volts, then get some diodes big enough to handle the generator output. Hook the generator up in parallel to the batteries through the diodes on both the positive and negative sides. The diodes will isolate the charging circuit from the starter circuit.

I am working on the same set up
delco 119845 is a 2-stage 24 volt (some listings show 12-24 volt)
119844 is a 3-stage 24 volt 119866 is 1stage 12 volt
I think they all have 12vt pull-in coils but real sure yet.
Motor City Reman in Detroit has the best pricing . All the Marine suppliers
seem to have higher prices. the major automotive suppliers don,t show a listing,
using the internet anyway( its hard to navigate around the web sites when they ask
for what vehicle in the search)
the diode trick seems good but what would happen to the generator if they shorted before they burned open?

Here are the circuits and switch for two styles ....

My info shows 1119866 to be a heavy duty relay only for 12/24v
Not a series parallel switch.

OM,

So, when you hit the start button and connect the batteries in series to start on 24v, does the 12v equipment die until you let go of the starter button and reconnect the batteries in parallel?

John

Any electrical system, no matter how basic should have fuse protection in the design.

Any electrical system, no matter how basic should have fuse protection in the design.

In normal position the bateries work in paralell and charge each set of batteries. In the early days no 12v were used at all they used 2- 6 volts on each side in series and when you hit the starter button the paralell swich disconects from 12v and and conects curcit in series making 24v when you let off the button it goes back to 12. But when they foul up 24v feeds back and burns out the voltage reg and every light bulb that is on and the deff fan and heater fan go crazy LOL I used to drive couple old Macks when that set up didnt take long to scrap that set and put 12v starter and 4 12v bats hooked pararel

I'm not recommending going to the series-parallel switch but if you must this is what you need and how to hook it up. Be prepaired for a unique wiring arrangement that probably no one else will be familiar with if there is a problem.

Considering the 3-collar switch is about $200 and the 2-collar about $150
I'd put the money into a 24v generator/alternator.