Strange symptoms - dirty plug prongs? (50amp)

[eric@babin.com]

Here is one for you.....

2014 Itasca Ellipse 42QD (all electric)

Symptoms:  EMS shows "no service", yet everything seems to be working. (except washing machine, but I THINK that may be a separate issue... or was it caused by this?)

When scrolling through EMS it goes from wiring "OK" to "error" back and forth.  

I, thinking maybe my surge protector (Progressive Industries EMS - PT50x) was damaged so I plug in to pedestal without it.  Same issues going on, so it isn't the surge protector.

I then grab my 50amp extension cord and plug into the pedestal next door. Everything is now working fine.  I plug the surge protector back into my space's pedestal.... everything reads fine, Volts at 123/124, 60 Hertz, and no errors.  So, I unplug my extension cord from the pedestal next door and back into my surge protector on my pedestal.  Everything is now working fine. 

Here is what I THINK may have been the problem, let me know what YOU think.

Is it possible the prongs on my 50amp were dirty or corroded a little.... with the plugging in and out, it cleaned the prongs and made good contact?

Today I'm going to use a fine grit sandpaper to clean the prongs even better.....

What are your thoughts?  Could that have been it?  Or am I going to see this phantom problem come back again and again? 

[wolfe10]

Sure, a  bad connection, either because of dirty or corroded prongs on your cord OR the outlet itself (at least as likely) could cause your symptoms.

[kaypsmith]

Agree with Brett, probably a combination of dirty prongs on your end and also dirty inside the CG outlet. Best to always turn off the CG breaker before plugging or unplugging both surge protector and the coach cord, this will help lesson the dirty (heat caused corrosion) on your plugs as well as the CG outlet. The black look on the brass is caused from heating and cooling of those plugs. Part of my semi annual projects is to clean my plugs then smear on then wipe off No-lox on all of these plugs, this also helps make plugging and unplugging a little easier.

[rayin]

Your plugs may be fine, the 50A receptacle contacts may be what is corroded or "varnished" to the point they prevent a clean connection. Remember, the pedestal receptacles get a lot more use than your plugs, they become worn and lose their spring tension due to generated heat. This causes your relatively new plugs to appear like they do not work properly.

I would not use sandpaper because it removes some metal with every use. Liquid/spray contact cleaner might be a better choice. Yes, the act of unplugging/plugging in likely did clean the connecting contacts enough to  rectify the problem.

FWIW, the spray contact cleaner may be used on the pedestal receptacle contacts without danger, just remember to switch off the main breaker.

[eric@babin.com]

On 5/30/2019 at 7:45 PM, RayIN said:

Your plugs may be fine, the 50A receptacle contacts may be what is corroded or "varnished" to the point they prevent a clean connection. Remember, the pedestal receptacles get a lot more use than your plugs, they become worn and lose their spring tension due to generated heat. This causes your relatively new plugs to appear like they do not work properly.

I would not use sandpaper because it removes some metal with every use. Liquid/spray contact cleaner might be a better choice. Yes, the act of unplugging/plugging in likely did clean the connecting contacts enough to  rectify the problem.

FWIW, the spray contact cleaner may be used on the pedestal receptacle contacts without danger, just remember to switch off the main breaker.

Good point regarding sandpaper... when I was in the Navy we used tabasco sauce to shine up brass... that would probably work. 

Also great idea regarding contact cleaner... I'm going to get that. 

So far, since the initial issue, we have had no problems. 

Thank you everyone for your advice!