Can a single pedestal have a low voltage problem?

**GaryS1964** · 05-19-2022, 12:54 PM

My question is can a single pedestal experience an intermittent low voltage problem when all the other pedestals on the circuit are functioning normally?

I was at a KOA recently and was attempting to run my A/C. It would start but the EMS cut the power and reported a low voltage error code. The EMS display was reading between 104 and 107 and sometimes dropped down under 100. The park was full and according to the staff no one else was reporting a problem. My brother in law who was staying a few sites away which according to the staff was on the same circuit didn't have any problems. The low voltage incident damaged my A/C and the compressor would no longer start.

The night before I ran my A/C without incident and the EMS was reporting voltage of 115 to 120. The day after the low voltage incident it was normal all day until early evening. We had gone to my brother in laws trailer to stay cool and when we came back to our trailer I noticed the EMS was again displaying a low voltage error code although it was reporting normal voltage. I assume that while we were gone the voltage had dropped below the 104 volts threshold where the EMS cuts power.

So my question is can a single pedestal experience an intermittent low voltage problem when all the other pedestals on the circuit are functioning normally?

**Second Chance** · 05-19-2022, 01:05 PM

Have you checked the plug on your power cord for pitting or discoloration (signs of arcing or overheating). You could have an intermittent bad connection at the plug on the pedestal. If you have a portable EMS rather than a hard-wired, check the plug prongs on both your power cord and EMS. We've also had three incidents where the 50 amp breaker (in your case it would be the 30 amp breaker, I believe) in the pedestal was bad. In one case, rapid cycling caused some damage.

Rob

**GaryS1964** · 05-19-2022, 03:02 PM

Originally Posted by Second Chance

Have you checked the plug on your power cord for pitting or discoloration (signs of arcing or overheating). You could have an intermittent bad connection at the plug on the pedestal. If you have a portable EMS rather than a hard-wired, check the plug prongs on both your power cord and EMS. We've also had three incidents where the 50 amp breaker (in your case it would be the 30 amp breaker, I believe) in the pedestal was bad. In one case, rapid cycling caused some damage.

Rob

There is no discoloration or pitting on the power cord plug. We have a hard wired Progressive Industries EMS. The EMS remote display is mounted on the control panel which on our trailer is always visible when sitting in the theater seats with table across from the TV. it is almost annoying. I've gotten use to it and tend to watch it go through a cycle or two whenever I glance up from what I'm doing at the table. That's how I first noticed the low voltage error code the day after we had the major problem.

I'm pretty sure the campground doesn't believe me and will do nothing regarding my complaint. I feel sorry for the next person they put in that space that has some damage caused by low voltage. We missed out on a three week trip to see the Arizona and Utah national parks we haven't seen before and it's doubtful we will try and go again.

I have an appointment next Tuesday to get the A/C fixed. I'll know more then about what may have caused the problem.

**xrated** · 05-19-2022, 03:25 PM

Originally Posted by GaryS1964

There is no discoloration or pitting on the power cord plug. We have a hard wired Progressive Industries EMS. The EMS remote display is mounted on the control panel which on our trailer is always visible when sitting in the theater seats with table across from the TV. it is almost annoying. I've gotten use to it and tend to watch it go through a cycle or two whenever I glance up from what I'm doing at the table. That's how I first noticed the low voltage error code the day after we had the major problem.

I'm pretty sure the campground doesn't believe me and will do nothing regarding my complaint. I feel sorry for the next person they put in that space that has some damage caused by low voltage. We missed out on a three week trip to see the Arizona and Utah national parks we haven't seen before and it's doubtful we will try and go again.

I have an appointment next Tuesday to get the A/C fixed. I'll know more then about what may have caused the problem.

I would also check the screw connections inside the EMS.....make sure you KILL all 120VAC power to the trailer before opening up the EMS box. Make sure that the screw terminals are tight and also look for any kind of arcing/burning in there. It is very possible that there could have been a loose connection on the shore power receptacle. Many of the RV park handymen know just enough about electrical stuff to be dangerous, so I would never put much faith in their troubleshooting or saying that their equipment was not at fault.

**BeerBrewer** · 05-19-2022, 09:50 PM

These are all valid sugestions, but yes, it is possible to be at a bad power pedestal. We've run into this too and the campgrounds almost never accept responsibility. They either claim that my Prpgressive Industries surge/low voltage protector is broken or they blame the power company. It seems to happen on hot days when everyone is running their AC. When it does happen and if there is 50 amps available at the pedestal, then I break out my 50 amp 240v to 30 amp 120v conversion plug and try plugging in that way. Sometimes that works. Keep in mind that we only have a 30 amp trailer.

**Steven@147** · 05-20-2022, 05:28 AM

Campground site power pedestals are some of the most abused connections. Cracked receptacles, weak breakers, very old plugs, corroded connections and such. Circuit breakers are not really switches and they get overloaded and trip a lot so they get week. During hot summer months is when low voltage usually shows up because everybody is running their AC units. Low utility power, inadequate sized transformers and or wire size and run length at the campground are some other causes. Other people might not complain about low voltage because they might not have a power monitor to tell them they have low voltage. Sometimes older campgrounds have more of a problem with this than new just built or renovated campgrounds.
EMS power protection are supposed to protect your rig from damage due to low/high voltage, spikes, neutral or ground problems and such by turning off the power. I suppose constant low voltage just above the EMS cut off point could damage an AC unit over time. On our PI EMS hard wired unit I think if the power drops much below 107V its the cut off point.

About all you can do is try another connection, like run on the 50 amp with an adapter to 30, depending on your rigs power requirements, switch sites or try another campground.