Charging 24v system with tow vehicle

[NeWcS]

I live in a apartment and because of this the only way to charge my trolling motor batteries is through my tow vehicle. Its no prob now seeing how I have a 12v system and can just charge from my truck. But I want to upgrade to a 24v motor. Will this work:

Thank you!

-Jay

 

[Silvertip]

Re: Charging 24v system with tow vehicle

Nice try -- but no. It's terribly inefficient. What you do need is a switch that breaks the series connection between the two batteries and parallels them so they become one large 12V battery. Some of the older boats had a Charge/Run switch on them for this exact purpose because 24V chargers were not readily available. The switch would be placed in the Charge setting and you feed +12V from the truck to the trolling motor plug. I'll see if I can find the diagram.

 

[NeWcS]

Re: Charging 24v system with tow vehicle

I'll see if I can find the diagram.

That would be cool.

So you think it could work with some sort of switch?

-Jay

 

[Silvertip]

Re: Charging 24v system with tow vehicle

Patience son -- I'm working on it! Yes it will work.

 

[Silvertip]

Re: Charging 24v system with tow vehicle

Check your private messages.

 

[External Combustion]

Re: Charging 24v system with tow vehicle

Silvertip: Did you give him the 12-24 relay set up that is common on our diesel road tractors?

 

[DJ]

Re: Charging 24v system with tow vehicle

Care to share?

Many vehicles, with factory (Class IV) trailer harnesses, have 30+amp 12v available for charging travel trailer "house" batteries.

Charging boat batteries is a definite possibility.

I've charged 12 v. boat batteries from the tow vehicle but not a 24 v. set up.

 

[Silvertip]

Re: Charging 24v system with tow vehicle

I was afraid this was going to happen and that's why I elected to make this a one shot deal via private message. The main reason I won't share this is because of the possibility of back feeding 24V into the tow vehicle if a blocking diode is not used. How could that happen? Well, this is a manual system (no electronics involved). Improper use WILL cause sparks and smoke. Anyone with an electrical/electronics background can figure this out so they don't need my help to design a manual or electronic system. There is a substantial amount of heavy gauge wiring that needs to be done on systems of this type and most people simply don't have the tools or knowledge how to do it. And I don't want to be blamed for mistakes they made. Fair enough??

 

[DJ]

Re: Charging 24v system with tow vehicle

I was afraid this was going to happen and that's why I elected to make this a one shot deal via private message. The main reason I won't share this is because of the possibility of back feeding 24V into the tow vehicle if a blocking diode is not used. How could that happen? Well, this is a manual system (no electronics involved). Improper use WILL cause sparks and smoke. Anyone with an electrical/electronics background can figure this out so they don't need my help to design a manual or electronic system. There is a substantial amount of heavy gauge wiring that needs to be done on systems of this type and most people simply don't have the tools or knowledge how to do it. And I don't want to be blamed for mistakes they made. Fair enough??

Check your PM's.

 

[wire2]

Re: Charging 24v system with tow vehicle

Nice try -- but no. It's terribly inefficient. .........

Actually, not that bad. Inverters and transformers (as in a charger) are up in the 95%+ area.

It's motor-generator combinations that are down to 25% or less.

But it would need an inverter sized to the load; e.g. a 10A 24v charger needs 20A at 12v, + 10% losses, is ~ 264 watts. 300 watt models are readily available.

I've run a laptop with a dead battery on a 75 watt inverter, it got a bit warm but kept up.

 

[Silvertip]

Re: Charging 24v system with tow vehicle

That may work for a 12V system but he's looking at a 24V system so some switching is needed. If he wants to pop for a new dual bank charger that raises the ante some more in the inverter power department. Electronics is not a cheap way to do this.

 

[roscoe]

Re: Charging 24v system with tow vehicle

Now all you have to do is drive around for 6 hours to charge the batteries.

Seems it would be worth the 5 minutes to disconnect the batteries and bring them into the apartment for charging.

 

[wire2]

Re: Charging 24v system with tow vehicle

Now all you have to do is drive around for 6 hours to charge the batteries.

Seems it would be worth the 5 minutes to disconnect the batteries and bring them into the apartment for charging.

It would keep him in good shape too, if he's in the 4th floor with no elevator.