Lister Engine Forum

How to / DIY => Generators => Topic started by: guest23837 on June 06, 2018, 01:52:22 PM

Title: Charging a 12v battery
Post by: guest23837 on June 06, 2018, 01:52:22 PM
Well guys the generator is up and running currently on a pull start. I have a starter bits of wire etc to connect it up however the rectifier is missing. The generator has 12v, 115 and 240 v outlets can I simply use the 12v outlet to keep the battery charged? I would like it to start electrically for the missus. Thanks
Title: Re: Charging a 12v battery
Post by: ajaffa1 on June 06, 2018, 02:07:40 PM
Hey Johndoh, Well done for getting your generator running. I think we need a bit more information before anyone here can give you useful advice, a picture tells a thousand words. Missing rectifier? is this on the DC/charging side of things or is it a rectifier used to feed the field windings to generate AC?

Bob
Title: Re: Charging a 12v battery
Post by: guest23837 on June 06, 2018, 03:12:14 PM
There is a coil under the flywheel with wires coming out of the side of the engine. There is supposed to be a rectifier there (photo attached) but it's missing. There is also a 12 v outlet on the control panel I assume its working as the 115 and 240 parts are working. I would like to use this to charge the battery if possible. The whole machine cost €50 and a rectifier is €60 that goes against my Scottish 1/3. I'm getting about 3 volts from the coils

Title: Re: Charging a 12v battery
Post by: EdDee on June 06, 2018, 03:38:12 PM
Hi JD,

Mine also went legs up....I have never replaced it (Also probably a hybrid Jew/Scot in my past).... Instead of using that, I just have a small battery conditioner/charger hooked up to the mains permanently....

Regds
Ed
Title: Re: Charging a 12v battery
Post by: guest23837 on June 06, 2018, 03:43:44 PM
That would work! Somewhere in the shed is a booster pack from Aldi or Lidl that would work ?
Title: Re: Charging a 12v battery
Post by: EdDee on June 06, 2018, 03:54:05 PM
Not sure JD.... Don't know the units personally... Hit Goog university for some info!
Title: Re: Charging a 12v battery
Post by: guest23837 on June 06, 2018, 04:24:45 PM
rectifier on amazon UK for £13. I did a little research and the 12v outlet on a generator isn't regulated so it wouldn't take account of how much charge is in the battery. The Aldi booster is supposed to start a 2.0 diesel car it will need to be charged for testing as it's not been used in years. Really the rectifier charging a small battery from the coils would be best as easier for the missus to operate. Just changeover switch, start the generator and count to 100 before throwing up the breaker.
Title: Re: Charging a 12v battery
Post by: guest23837 on June 07, 2018, 12:17:30 AM
Thank you for the information Mr Glort to be honest I'd rather talk naked about erectile dysfunction to a bunch of nuns than attempt electrical repairs.. I know my machine has a bridge rectifier but I have no idea where the wires go. I assume if I attach this

https://www.amazon.co.uk/gp/product/B077RFN4PZ/ref=ox_sc_act_title_1?smid=A10C9AX1J5P100&psc=1

connect the plug and run the other wire to the battery it will charge said battery?
Title: Re: Charging a 12v battery
Post by: mikenash on June 07, 2018, 12:45:28 AM
Hi JD,

Mine also went legs up....I have never replaced it (Also probably a hybrid Jew/Scot in my past).... Instead of using that, I just have a small battery conditioner/charger hooked up to the mains permanently....

Regds
Ed

In our line of work we have customers with older gensets that have inbuilt 12 VDC chargers.  When they fail I just buy a good-quality off-the-shelf battery charger and hardwire it into the 230VDC leg and attach to the battery.  That has always been a simple, cheap solution
Title: Re: Charging a 12v battery
Post by: guest23837 on June 07, 2018, 01:10:25 PM
I found the wires coming from the bridge rectifier they ens in 2 wires one red one black on a volt meter they read 25.2 volts. Looking through the little box of parts that came with it there is a little electronic box of tricks and a load of wires attached but what they do is beyond me. The 25 volts is DC so I am thinking it could be reduced to 14 ish and regulated???  This is the part where I stopped trying to figure it out and fitted my new exhaust. It's bearable! no louder than the Yanmar L48 so I'm happy enough with that for now. I know a lot of you guys find electrics as challenging as patching an inner tube, I can do the tube this is beyond me. I downloaded the manual and wiring diagrams for this engine, it's like trying to read Sanskrit in the dark wearing sunglasses.
Title: Re: Charging a 12v battery
Post by: guest23837 on June 07, 2018, 07:11:35 PM
So I'm back to the beginning. for the moment I will ignore the bridge rectifier and concentrate on the coils (dynamo) under the flywheel that connects to the 12v charging rectifier. I checked and the coils actually put out 25v AC would this be correct? does the rectifier convert the power to 14v DC? do I need to connect anything between the rectifier and the battery? Should I stick to the pull start?

It's all academic now as I have the wrong starter it's off a Kubota garden tractor and useless. Rope start it is and rope start it will remain!
Title: Re: Charging a 12v battery
Post by: guest23837 on June 08, 2018, 08:29:55 AM


The penultimate paragraph in your reply is enough to make me feel like hiding under the table. "Star and delta wiring, Capacitance, flashing field windings, frequency, AC/DC, 3 phase Rectifiers, voltage sag, C2c configurations....."!

I really just like the idea of having electricity during a power cut something none of my wealthy neighbours have. I have a small very noisy Yanmar L48 generator I have the Lister project which may at some stage become a 12v system with an inverter and theres a 2 stroke Chinese generator that was sitting for 3 years now it hunts and splutters, needs a carburettor I think. The Lister really needs a total rebuild those old cement mixer engines are badly treated and parts are expensive so thats a slow burner no pun intended.

The starter that came with the generator is off a Kubota tractor it works well and is worth more than what I paid for everything it's going to be an easy sell it's Denso not Chinese rubbish.

Here's an odd thing, "Home and Away" is on television around lunchtime and it's repeated after the evening news I assume this is because nobody can believe it on the first viewing.  Anyway I was out in the shed yesterday evening and the wife came out and said "stop starting those fcuked engines I can't hear a thing" I pointed out that a "fcuked" engine might not actually be able to be started and that saying stop starting is grammatically poor. She said "you're a stupid B. turn them off"

I can't win
Title: Re: Charging a 12v battery
Post by: guest23837 on June 08, 2018, 10:58:36 AM
BRILLIANT!