We had added two new 8D AGM batteries this past May as the old ones were cooked! But the existing battery charger was not designed for AGM batteries, so it had to be replaced. Since we already had a Xantrex inverter onboard, I chose to stay with Xantrex and installed the TrueCharge2 40A charger. It was not difficult to do, although I was hesitant as I didn’t want to goof anything up!
The old charger was mounted on the inside of the starbard aft lazarette, so after removing the electrical connections (it only sparked once when two wires touched together!) I was able to remove it. Talk about heavy! The new charger is significantly lighter and was easier to maneuver into place. I did have to drill new holes as well as the new one is way smaller than the old one.
One of the crimps on the existing wiring came loose, but thankfully I purchased a hydraulic crimper for the electric windlass installation as I needed to crimp a new lug on. The new charger is a three bank charger, as was the old one. This means there is a separate connection to each of the three batteries we have on board: Two house batteries and a Starting battery. The Starting battery, dedicated solely to start the engine, is not an AGM battery so I may have to replace that at some point.
I also ran the wiring for a remote battery monitor to the instrument panel. I was hesitant to do this as it was a hassle to run it there, but now that it is installed I really appreciate what it’s telling me. I can track when the charger kicks in, how much it is being charged at a time, when it’s in the float/ready stage, and the overall condition of the batteries. I also have an existing voltmeter that continues to work.
Initially, I saw a huge difference in the charge flowing into the batteries from the charge, and it equalized what was going into each battery. With the old one, battery 3 always read lower – don’t know why.