Inverter Connections to Battery Failing

[chris07732]

I'm experiencing persistant problem with connections from battery buss bar to my Xantrex inverter/charger. After several months of limited use with no problems, charger suddenly doesn't sense battery is connected, won't go into charge mode. To resolve problem, I have to disconnect the 2/0 cable lugs on the charger, lightly file the lug surfaces, reconnect and charger starts right up. The cable connections to the Xantrex are tightened with a ratchet, so they are not loose, they do not show any sign of corrosion.

Is this a Xantrex issue? Is there a conductive paste I could use to coat the terminal surfaces?

[onestepcsy37]

might not be corrosion. might be just disconnecting and reconnecting that does the trick, allowing the internal 'computer' to reset itself. if so, might be something internal to the charger/inverter...

[Florida Mike]

Copied from a GOOGEL source.
With the metal connections visible, squeeze a small amount of dielectric grease onto the q-tip. Rub the grease over the entire metal surface of each connection. You don't need very much to do the job, but be sure to get a good layer all over. Plug your connection back together and you are now protected from the green monster of corrosion.

[Stu Jackson]

WADR, that is wrong. Dielectric grease is an INSULATOR, the very LAST thing you want on terminals.

Dielectric means it blocks electrical flow. There is a study out there comparing dielectric to no dielectric on antenna connections and the dielectric definitely cuts into performance. I read this a few years ago and found another alternative.. I put together clean connections, with a little DeoxIt Shield or DeoxIt D5 and then 100% seal them...
There is nothing wrong with applying dielectric after the connection has been made but then it is nearly impossible to seal it with tape because nothing sticks to silicone.

[djmarchand]

Dielectric grease is good stuff for preventing corrosion on electrical parts either before or after, it doesn't make any difference in connection conductivity.

But as the other poster suggested, I suspect you have an inverter problem and disconnecting and reconnecting power resets the inverter. You might try hitting the reset button to see if it does the same thing.


Which inverter is it, the Freedom series, the newer MS series or the crappy ProSine series?


David

[Florida Mike]

Originally Posted by Stu Jackson

WADR, that is wrong. Dielectric grease is an INSULATOR, the very LAST thing you want on terminals.

Dielectric means it blocks electrical flow. There is a study out there comparing dielectric to no dielectric on antenna connections and the dielectric definitely cuts into performance.

I think you will find that dialectic grease is actually a conductor and that is why it does not work on antenna connections ( it shorts them out). I have been using the four years on electrical connections. Just my two cents, Mike.

[Sailmonkey]

Originally Posted by Florida Mike

I think you will find that dialectic grease is actually a conductor and that is why it does not work on antenna connections ( it shorts them out). I have been using the four years on electrical connections. Just my two cents, Mike.

From Wikipedia

Dielectric grease
Dielectric grease is electrically insulating and does not break down when high voltage is applied. It is often applied to electrical connectors, particularly those containing rubber gaskets, as a means of lubricating and sealing rubber portions of the connector without arcing.
A common use of dielectric grease is in high-voltage connections associated with gasoline engine spark plugs. The grease is applied to the rubber boot of the plug wire. This helps the rubber boot slide onto the ceramic insulator of the plug. The grease also acts to seal the rubber boot, while at the same time preventing the rubber from becoming stuck to the ceramic. Generally spark plugs are located in areas of high temperature, and the grease is formulated to withstand the temperature range expected. It can be applied to the actual contact as well, because the contact pressure is sufficient to penetrate the grease. Doing so on such high pressure contact surfaces has the advantage of sealing the contact area against corrosion.
Another common use of dielectric grease is on the rubber mating surfaces or gaskets of multi-pin electrical connectors used in automotive and marine engines. The grease again acts as a lubricant and a sealant on the nonconductive mating surfaces of the connector. It is not recommended to be applied to the actual electrical conductive contacts of the connector because it could interfere with the electrical signals passing through the connector in cases where the contact pressure is very low. Products designed as electronic connector lubricants, on the other hand, should be applied to such connector contacts and can dramatically extend their useful life. Polyphenyl Ether, rather than silicone grease, is the active ingredient in some such connector lubricants.
Silicone grease should not be applied to (or next to) any switch contact that might experience arcing, as silicone can convert to silicon-carbide under arcing conditions, and accumulation of the silicon-carbide can cause the contacts to prematurely fail.

[Stu Jackson]

Thanks, sailmonkey. The incorrect application (pun intended) is skippers slathering the grease ON the contacts. The concept is to make the connections clean, connect them, and cover with grease afterwards to keep corrosion out.

[btrayfors]

Stu and SailMonkey are absolutely correct. "Dialectric" means "insulating". Dialectric grease is non-conducting. It's great for coating AFTER connection has been made. Folks generally get away with using it on conductors, because the conductors are tightly pressed together and either wipe off or squeeze out the dialectric grease.

As to the problem posed by the OP, I'd suspect the connector-to-cable terminations. There may be poorly installed or otherwise compromised connectors on those cables, and when they're removed they wiggle enough to make a sort-of connection.

Bill