12 volt to 24 volt wiring question

[buzzbait2000]

I just bought this boat and it had a 12 volt trolling motor on it. I just installed a 24 volt trolling motor on it. I have already added a second battery and connected them negative to positive as instructed.<br /><br />My question is the 12v motor only had two wires a red and black. The 24v has three wires, red, black, and white.<br /><br />Is the white wire an additional hot wire? Do I need to run a white wire from the trolling motor back to the positive side of the battery along with the existing red wire?<br /><br />The motor actually runs with just the two wires but I do not think it is running properly (fast enough).<br /><br />Please help!!

 

[Silvertip]

Re: 12 volt to 24 volt wiring question

You need to check with the motor manufacturer to verify wiring instructions. However, I think what you will find is that you need to undo the current battery wiring. Connect the two NEG terminals together. The white wire from the motor connects to either NEG terminal. The BLACK wire from the motor connects to the POS terminal on one battery and the RED wire from the motor connects to the POS terminal on the other battery. You essentially are feeding two separate 12V sources to the motor. 24V is being taken care of in the motor. Without knowing the motor type, this is speculation on my part so make sure you verify this.

 

[buzzbait2000]

Re: 12 volt to 24 volt wiring question

I guess I do not understand what youy are saying. If I unhook the negative to positive on the battery I will no longer have a 24v system. I will have two seperate 12v systems.<br /><br />Also if this helps the motor is a 1993 motorguide 575 with 65 pounds of thrust.<br /><br />The old 12v motor was wired red to + and black to -<br /><br />You are telling me that it is supposed to be red to + and black to + and run a white wire to -

 

[Silvertip]

Re: 12 volt to 24 volt wiring question

Almost! Make sure the NEG terminal on both batteries are connected together and that the white wire connects to either one. And I'm also saying be sure to check with MotorGuide before doing this. I checked their web site and there is no information shown for this wiring scheme (it's not commonly used any longer). You need to call them. Your house doesn't have 220 volts on two wires either. It has two separate 110V circuits that when measured across produces 220V. As I said, two 12V circuits feed the motor and the motor takes care of the 24 volt requirement internally. Its how the motor is wired and wound internally. Some 24 volt motors had four wires going to the plug so they would run either on 12 or 24 volt.

 

[Marc J.]

Re: 12 volt to 24 volt wiring question

Did you get your wiring dilemna solved Buzz? Not to question Upinsmoke's response, but I used a wiring digram off an Attwood three-prong connector. It differed in that the grounds were not connected. I suspect that your TM is a 12/24V model since you have three wires.

 

[Silvertip]

Re: 12 volt to 24 volt wiring question

If the grounds were not connected at the batteries, they were likely connected at the same terminal on the connector -- that makes them common and exactly the same electrically as my scheme. The difference is only that you don't need to run two wires (one from the negative terminal on each battery) to the connector.

 

[litldvel]

Re: 12 volt to 24 volt wiring question

Buzzbait, if your dilemna is not solved hopefully it is by now, but just in case. I have just taken an old 12/24 MG motor off an 88 Tracker. It had the three wires on the plug. Mine was wired so I could switch from 12 to 24 on the foot control. Your red wire most likely is the 12volt+ and your white wire is your 24volt+ the black is the common ground. You can use just two wires but you will not be able to switch between a 12/24. And you will have to make sure that your positive wire is on the right battery in the series. I would say that is why it is not running as fast as you think it should, probably only getting 12 volts. Hope this helps.