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Saturday, February 2, 2002

Preventive Maintenance Help for RV Electrical Systems



Ponder for a moment just how many items on a modern recreation vehicle are powered or energized by some form of electrical current. The vast majority of the propane-burning appliances and quite a few of our other amenities are indeed electrical in some sense. Because of the advances in electronic applications, gone are the days of “overriding” the system or “by-passing” the controls of analog devices. Today, without a healthy 12-volt battery system it is nigh impossible to even light the refrigerator or operate the furnace let alone find that satellite, make those ice cubes or spin those disks (CD and DVD, that is).

Whether we take into account high voltage or low voltage, battery power, inverter output, shoreline, generator power or solar power, each circuit that uses electrical current involves a power supply of some type, a resistive unit of some type and a method of delivery of some type. This treatise is purposed to bring to your attention not only problems that may sometimes wreak havoc on your RVing travel plans, but to also bring to the table a solution, a preventive cure that will help minimize those problems, if not eliminate them altogether.

The method of delivery alluded to above is usually facilitated by the use of electrical conductors or wires. Batteries are “wired” together; the appliances are “wired” into the system, the converter “wires” the AC system to the DC system, etc. In a perfect world, these wires run, unabated, from the power supply to the electrical product and many times back again. The ending points for most of these wires involves some method of termination. Some are connected to screw-type terminal blocks; some are attached using crimped-on ring or spade terminals. 


Many are connected to a plastic multi-plug encasing many wires at once which then connects to another multi-plug or slips over thin, edge traces on printed circuit boards, similar to those in the photo here.




 
Virtually all LP appliances, roof air conditioners, monitor panels, generators, converters, radios, inverters, etc., will all use some form of a multi-plug connection. Therein lies the bugaboo. At any point where a wire is terminated and connected to a device, there is also the probability of electrical contamination manifesting itself over time; contamination that includes metallic oxides and thin layers of chloride film.

We’ve all seen the worst of neglected battery terminals, which seemingly have living green and yellow organisms growing around the terminal wing nuts. Granted, many of us would indeed take the time to clean those battery terminals, most likely because the neglect is easily visible. But how many of us would take the time and spend the effort to ensure the circuit board contacts are clean and bright on the appliances, or that the shoreline cord contacts are clean, etc. What about the umbilical between the truck and that fifth-wheel trailer behind you? The fact is, many of the ills associated with erratic LP appliance operation and battery charging and discharging, just to name two areas are directly attributable to contaminated contacts on the printed circuit boards or at the multi-plug connections. I would wager that the majority of electrical symptoms are a direct result of corroded and oxidized contact points at wire terminations. And most are avoidable.

It has been written and proved many times over that the physical and chemical changes in the surface condition of electrical or electronic connectors are the primary causes of degraded performance of components and equipment. Add dust, soot, smoke and other gunk that hangs in our atmosphere and strange discolored films will form on the contact surfaces impeding the flow of electrons. Oftentimes the result is erratic operation of appliances, less than pristine battery charging, blown fuses, sticking relay contacts, poor electrical grounding and bonding, etc., amid other intermittent ills often blamed on the battery or other components. 

I’ve seen LP appliance printed circuit boards replaced erroneously when the cause all along was simply an oxidized contact strip on the edge connector. Technicians, unfortunately, often fail to inspect these important contact points and are lulled into a false sense of accomplishment when the new circuit board fixes the problem. Fact is, installing the new board simply scraped away some of the contamination enough to make a better contact; albeit temporarily. Unless the process is stopped, that new board will be diagnosed as “faulty” soon enough also. The same, temporary result would have been effectuated by simply unplugging and plugging in the old board a few times. 

Oxidized contact surfaces as well as chloride films, (prevalent in coastal communities especially), indeed require periodic attention. Cleaned and treated annually, most electrical dysfunctions can be avoided by effectively ridding contact points of such contaminants. So what’s the solution? There are many contact cleaners available, but most only apply a physical “washing” to an area that is predominantly in need of chemical attention. Here’s why:

Oxides, sulfides and forms of chloride contamination physically attach themselves to the thin layers of the contacts on most printed circuit boards. Though more evident with gold plated contacts, still the thin traces of RV appliance boards are negatively affected and become “blistered” to the point of causing added resistance to that portion of the circuit, (see photo above). This added resistance simply impedes the performance of any electronic function and can be the cause of intermittent operation. The technical term for this blistering is called dendrite corrosion, but the result is that the contact portion is greatly reduced, almost insulated to a degree and erratic operation of that appliance is sure to follow and only get worse as time goes on. Simple contact “cleaners” may wash away dirt, dust and grime, but they prove ineffective at removing oxidation and surface sulfides because these tough contaminants, remember, actually attach and become an integral part of the contact metal. The only true method of eliminating these contaminants is by chemical action and reaction. 

Enter some amazing products by CAIG Laboratories Inc. DeoxIT, specifically, is formulated to literally dissolve and remove these oxide blisters by chemical action. After treatment, a thin residue of organic make-up is left behind which coats the contact area thereby protecting the surface. Additionally, DeoxIT contains additives that prevent the loosened oxides from reattaching, ultimately eliminating them through the mechanical action of unplugging and plugging the board back in a few times. 


According to their Product Information Sheet, DeoxIT’s unique properties allow it to work on stationary and moving contacts and connectors with both similar and dissimilar metals. It will even migrate to an untreated contact, (such as a new, replacement board), when it connects to the previously treated connector plug. See if you can tell the difference between the “before" photo above and the “after” photo below. 

Take the time to check a couple of the printed circuit board contacts on your propane appliances. If you see any discoloration on the contacts, it is in need of treatment. Visible discoloration means severe oxidation has already taken place. It will only be a matter of time before erratic performance of that appliance will rear its ugly head. And, according to Murphy, it will usually happen at the most inopportune time. 

I have tested the advantages of DeoxIT and used the product for a few years now and have observed a definite increase in effectiveness of the devices I’ve treated. Not restricted to just RV appliance circuit boards and other multi-plugs, I’ve used DeoxIT on every battery device I regularly use; even the batteries for the digital camera that shot these photos, my iPhone and assorted flashlights, etc.


As a musician, I’ve even treated all the gear I use when playing live. CAIG Laboratories also offers a nifty package of lint-free wipes, swabs, applicators and cleaning brushes that will fit just about any application you may require. All serious RVers should consider adding DeoxIT to the tool kit. Because as you know, RVing is more than a hobby, it's a lifestyle!

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