Deckmount Converter
Deckmount Converter
By Perry Mack
Few things can be as mystifying to an RVer as their electrical system. You can’t ‘see’ anything flowing, you can’t ‘see’ if something is full. You can spend thousands of dollars upgrading your charging system to meet your needs when really, a little maintenance and a couple hundred dollars may be all that’s required.
The number one cause (and most easily fixed) of a poorly functioning electrical system is corrosion on the battery terminals. This slows or stops the healthy flow of electrons faster than plaque blocks blood in your heart. And we don’t want that. The flooded lead-acid batteries are the most prone. Gas rises from the water/acid solution in the cells and releases sulfuric acid through the cell vents creating a bluish or whitish ‘growth’ or film on your terminals.
When you see this it’s time for a cleanup. I’ve found that a steel brush is best. You can pick one up at your local hardware store or many RV dealers and auto parts stores sell circular battery brushes. You need to clean both the battery top posts and inside the battery cable terminal. If you don’t have a steel brush, baking soda and an old toothbrush will work. You may be tempted to use a bit of sand paper but this isn’t your best choice. The grit is often silica carbide (basically glass), which is an insulator. As you sand, bits of silica are deposited on the work surface, so you are actually depositing a different substance that will prevent the flow of electrons.
When you are done cleaning, make sure the connections are snug. If you can wiggle the terminals on the post, you don’t have a good connection. Check these periodically to make sure they remain snug.
The flooded (or wet cell) batteries suffer from fluid loss due to out-gassing. There should be roughly 5mm of fluid over the plates inside. Use distilled water (no minerals in there) and always wear protective eyewear and gloves as you are dealing with acid. Also, don’t wear your favourite pair of jeans or shirt. Any contamination from the battery and they could dissolve before your spouses’ eyes, eyes which will begin to roll as they shake their head and say something supportive like, “which part of ‘acid’ in ‘battery acid’ did you not understand”.
The advent of sealed lead acid batteries (also called maintenance free), Gel and AGM (Absorbent Glass Mat) batteries (fluid is in a gel or sponge like material) have done a lot to save relationships and clothing as they don’t require refilling and are not susceptible to corrosion.
The battery compartment can also become corroded so don’t put away that steel brush yet. Clean off the loose flakes of rust, feel free to use your baking soda solution again, and once it’s clean and dry, repaint with an anti-rust paint or apply a truck bed coating such as Al’s DIY liner for a like-new and maintenance free finish.
Your RV battery shouldn’t be allowed to remain discharged for long periods of time – essentially whenever you store it. Applying a trickle charge (usually 1.5 amps at 13.6 volts) will keep the battery in good condition. Your basic Canadian Tire special will do the job but there are several companies (I use CTEK www.smartercharger.com) that produce better models which not only apply a trickle charge but actually condition and restore maintenance free batteries by running them through a programmed series of charge and discharge cycles.
One improvement to your RV’s charging system I can recommend is upgrading from a single stage (most common in low- to mid-price trailers and smaller motorhome battery chargers) to a multi-stage power converter. Charging a battery is a lot like filling a tire with air. It’s easy to push in at the beginning but gets harder the closer you get to full.
A multi-stage converter increases the voltage to keep the amps constant, letting the battery accept as much current as it is willing until the battery is full and then it keeps it there. The bottom line is you get a faster charge and a healthier battery. Check out Parallax Power Supply’s 4445TC Deckmount Converter with also features reverse polarity protection and temperature compensation technology.
Converters are often tucked in out-of-the-way places and your RV parts and service department can help you find it, determine what kind you have, and if you need an upgrade, which model is right for you.