Positive ground

[Fordy20]

I have two tractors with positive ground that I would like to use my sprayer with. The sprayer of course is set up negative ground. Do I need to use a separate battery for the sprayer, or is there a way to hook it up to the tractor battery that won't hurt the sprayer motor?

 

[John730D]

if the pump motor has two wires, and is isolated from the frame of the tractor, just hook + to + and - to -.

 

[John B.]

Hook your sprayer up directly to the battery. Positive wire on your sprayer will go to the positive battery post and the other wire to the negative post. Don't worry how the battery is hooked up to your tractor. By connecting directly to the battery you won't be hooking to the tractor frame and have to even think how the battery is hooked to your tractor.

 

[Janicholson]

Both answers are OK but often the motor of the sprayer will be connected to the sprayer frame. If so it will cause drastic issues. Use a ohm meter from sprayer frame (bright and shiny metal of the hitch) to both of the sprayer leads (tractor not attached) If there is a connection at all it is a no go. Should read infinite ohms. Jim

 

[Den N Ms]

Is the sprayer 12 volt and your tractor 6 volt? If the tractor is 12 volt and the sprayer has 2 wires ,hook it directly to the battery as others have said. If the tractor is 6 volt the sprayer won't work very well.

 

[rvirgil_KS]

What are the 2 tractors? It likely would not be difficult to convert at least one of them to negative ground

 

[Texasmark1]

DC motors are polarity sensitive. If you expect it to run in the designed direction you need to maintain proper polarity.

If you have two completely separate "power loops" you can run your sprayer properly.

A power loop is a battery terminal connected to a load input (case or terminal) with the load output (case or terminal) returned to the other battery terminal. If only one point in the loop connects to another power loop, like the tractor's chassis for a "ground" reference, no problem.

Taking the JD 4020 as an example there were 2 batteries connected in series for 24 volt starting but 2 separate power loops ( 1from each battery) to power accessories in both the positive and negative directions....just maintaining the closed loop on each battery for the accessory.

Yes to answer your question, a separate battery, polarity connection as required, with only one connection point to the tractor/sprayer common "ground/chassis".

 

[Bob]

(quoted from post at 07:43:19 10/16/18) DC motors are polarity sensitive. If you expect it to run in the designed direction you need to maintain proper polarity.

"DC motors are polarity sensitive."

NOT true, generally speaking but TRUE with permag DC motors, which, likely, the spray pump motor IS.

But that's OK, as (typically) those units are not internally grounded to their chassis, but instead have a separate power (red) and ground (black) wire coming out of them to be connected to power.

Simply reversing the red and black wires will correct the roation when used with a (+) ground system.

On, depending upon what type/how big this setup is, it MAY be a simple diaphragm pump that will operate equally well running in either direction. (Check with manufacturer of pump.)

So a photo/more information is needed to be certain of what issues, if any, there may be here!

 

[oldtanker]

I think the issue here is going to be voltage. Most positive ground tractors are 6 volt and I've never seen a 6 volt sprayer before.I will hazard a guess that the OP is going to have to either find a different tractor or convert one over to 12 volt.

Rick

 

[Texasmark1]

Sorry should have included PM Stators.