Dear Dave,
I just cooked one of my two wet cell batteries (Interstate deep cell). Question: Is it a good idea to keep your 30-amp trailer plugged into a 120-volt source while parked at home for 30 days straight? Would it be better to get a satellite battery maintainer? —Paul
Dear Paul,
Leaving your rig plugged in or not when the trailer is parked at home depends on the type of converter/battery charger you have. Since you indicated it was a trailer, I would assume you have a conventional charger that puts out 13.6 volts when the battery draws down and then goes to 13.2 volts to just maintain the batteries. If you “cooked” one of your batteries, I would assume the converter is bad and did not go to the maintenance phase.
However, when lead acid batteries drain down, sulfur coats the plates. If you do not have a multi-stage charger or “conditioning” model, the sulfur gets thicker and thicker and eventually will not hold a charge. So, just leaving it plugged in or even using a satellite trickle charger will not condition them.
Since I believe your charger is no good, I would suggest looking at a new charger that has the conditioning or desulfation setting.
My recommendation is the Progressive Dynamics unit with Charge Wizard. Then you can leave it plugged in and the batteries should last 2-3 times longer. If you have an all-in-one unit, which has the converter inside the distribution center, and don’t want to replace the entire unit, you can just get the standalone version and disconnect your converter section of the distribution center.
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Dave – Trailer plugged in to 110V Since we bought our 1st trailer, which was a HI-LO more than 25 years ago, I installed a battery disconnect switch to keep the battery from draining. On all of our next full sized trailers I installed a designated 30 amp. outlet on it’s own breaker. This coupled with battery disconnect has kept our trailers cool in the hot Florida weather when not in use. I monitor the battery water level and have never had an issue with a battery or the trailers charging system.
When I have AC power, I stay plugged in. But there is another alternative – I have a 10watt solar charger specifically designed to vary voltage for conditioning the battery. I have set up a plugin port direct to the battery for convenience and have a battery disconnect switch that I know fully disconnects the TT. I also switched to AGM rather than flooded to avoid loss of water when unattended. At the house I plug in, but at the storage lot, I go solar. The battery has stayed in excellent condition.
Hi Dave.
Can you be a bit more specific on which charger? The link shows one for $14, up to $300+!
Dont be quick to condemn the charger. I boiled my golf cart batteries using a VERY expensive charger.I contacted the manufacturer and was told ” any one cell going or already bad and the charger will attempt to charge the set”. You have one cell and in the case of the golf cart24 cells and you have an expensive problem. I found that using a plug-in timer for 1/2 hour a day works best.
You are spot on about Progressive Dynamics replacement converters…way better than those junk WFCO …and some others that Manufacturers cheapen out on. PD makes a 12 volt side that is easy to replace without having to replace the entire converter Bestconverter.com is my go to for these parts.
Thank you, Dave! 🙂 Have a great day, safe travels, and safe stays! 🙂
Frankly, if you are going to replace your converter, replace it with one that will charge a lithium battery and then replace that old lead-acid battery with a lithium. Less weight and more power!