What Converter do I Need for Lithium Batteries when Replacing My Magnetek 6345?

Updated 09/29/2025 | Published 05/07/2025

Question:

5-7-25 1.45 pm ARIZONA TIME Must replace MAGNETEK 6345. I BELIEVE I NEED THE PD4645V, WITH ITS FUSE BOARD and WIZARD and wiring harness WILL ALSO BE BUYING LITHIUM BATTERY to replace lead acid battery 685 MCA/140 RC/ 24DC-DL marine rv. I am in fact copying infoI do not have any knowledge of the aboveI am 75 and learningnever owned RV pleaseprovide me all the help you for me to get this task doneSUCCESSFULLYso I do not need to modifyjust install this new PD4645 unit. THE OLD 6345 MAGNETEK IS STILL ATTACHED TO RVI will label each wire as I actually do the removal. I will greatly appreciate your expertise and assistance so I may get this task done correctlythe first time...thanks again. m mabry

asked by: Mary M

Expert Reply:

Hello Mary,

You’re replacing your old Magnetek 6345 converter with a new Progressive Dynamics # PD4645V, which is a great choice, especially since you're upgrading to a lithium battery. The # PD4645V is made to fit right into the old Magnetek box, and it’ll give you much better charging performance for your new lithium setup.

Before you touch anything, be sure to unplug your RV from shore power and disconnect your old battery, both the positive and negative wires. Safety first! Then, as you remove the old Magnetek 6345, go slowly and label each wire as you disconnect it. That’s a smart move and will save you a lot of confusion later.

Once you’ve got the old parts out, slide the new # PD4645V converter into the same lower compartment where the old one was. The new DC fuse board will replace the old fuse section, usually mounted in the door of the old box. The included wiring harness will connect the converter to the fuse panel, and from there you’ll just reconnect your AC and DC wires to the new board. Black wires are typically positive, and white are usually negative, but your labels will guide you.

The # PD4645V features a built-in jumper on its circuit board that allows you to easily switch between lead-acid and lithium charging modes (see the attached image for reference). Once you’ve set the jumper to the lithium position, you’re ready to install your new battery. Just be sure to connect it properly.

After everything’s hooked up, plug the RV back into shore power and turn it on. Check that your lights and appliances are working, that the battery is charging, and that the converter fan turns on (sometimes it takes a minute). If all that works, you’re in great shape!

Take your time, double-check your connections, and don’t hesitate to ask if something looks unfamiliar. You're doing a big upgrade that’ll give your RV a much more reliable electrical system for years to come.

I also attached a video that Kevin put together to help walk you through the install, you will even notice his nice blue tape and how he labeled along the way =)

Any big trips planned for when you tackle this big replacement? If so, where are you headed?

expert reply by: Kate F

Lithium Toggle on Converter
(click to enlarge)

Kate F.

9/29/2025

Hi Mary, Did you have a chance to install the new converter and set it up for your lithium battery? I'd love to hear how it went and if everything is working smoothly with your RV's electrical system now. Your experience could really help others who are looking to make a similar upgrade!