shore power

[nena lynn]

Plugged into 50 amp shore power, but control panel shows only have 30 amp power.Whats up?

[Darryl&Rita]

Bad wiring to pedestal, bad wiring within pedestal, or breaker issues.

[Britcon]

On some RV's, you need to set the incoming shore power amperage so your system doesn't try to pull more than you have available. Do you have a power management system on your gauge area ?

[Kirk W]

Are you by any chance using an adapter that connects a 30a power cord to a 50a outlet? That would give you only one phase of the power and probably will cause your 30a indication. If you happen to have connected a 50a cord to an outlet that has one phase missing, that too would likely cause your symptom. I checked and your profile gives us no hint of what motorhome you are traveling in so we have to guess as to just what you have. With a little more information we could give you better ideas.

[oldjohnt]

Nena, what's called 50 amp RV service (4 wires, 2 Hots, 1 Neutral, 1 Ground) has two hot legs L1 & L2, each of which are 120 volts with respect to Neutral. What's called 30 amp RV service (3 wires, 1 Hot, 1 Neutral, 1 Ground) has ONLY one hot leg which is 120 volts with respect to Neutral.

 

If you're plugged into a 4 terminal 50 amp RV outlet but ONLY have one Hot feed, that means one of the two 120 volt legs L1 or L2 is dead and may be caused by:

 

a) Faulty RV pedestal outlet or the wiring into it or circuit or breaker feeding it (IE one of the hot's is open or not connected etc)

Faulty RV Power cord or its plug/wiring or a receptacle that has one of the two hots open/broken

c) Problem in the RV panel like an open hot or a loose wire or connection

 

I don't what sort of an EMS or Monitor you have and where its located, but if typically BEFORE your RV panel and if it sees one leg is dead, the problem isn't in your panel but in the cord/service to the monitor or the monitor itself or its input cord or its male plug or in the RV pedestal or its wiring or outlet etc. per the above

 

I would start by checking the RV pedestals 4 pole 50 amp outlet to insure there is 120 volts from L1 to Neutral and 120 volts from L2 to Neutral and 240 volts L1 to L2. If NOT have the management repair the pedestal or its service. If all is okay at the pedestal but NOT in the RV (it depends on where EMS or Monitor is located) see the above and look for a dead/open hot leg caused by an open wire or loose/open connection or a bad plug or bad outlet.

 

Basically you have to start at the RV pedestal to insure two hot legs are there (L1 = 120 to Neutral, L2 = 120 to Neutral and 240 from L1 to L2) and if so then work towards the RV and its EMS or Monitor to and through them to the RV panel to see where you lose power in one leg (broke or loose wire or connection) .

 

My first "guess" (if you're plugged direct no adapter to a 4 pole 50 amp outlet) is the problems in the RV pedestal outlet and one leg is dead. Second "guess" is a power cord or its plug or an outlet problem and/or the wires to it. After that it could be a monitors plug or its wiring or other problem

 

In the event you had one of those 3 wire 30 amp Male Plug to 4 wire 50 amp female receptacle dog bone adapters to feed your 4 wire 50 amp RV YOU ARE ONLY GETTING ONE HOT LEG even if all is okay. A 3 wire 30 amp to a 4 wire 50 amp dog bone adapter into which you plug your RV power cord ONLY PROVIDES ONE LEG OF 120 VOLTS AND A GOOD MONITOR OR EMS WOULD INDICATE SUCH AS A 30 AMP SERVICE IE ONE DEAD/MISSING LEG...

 

If you can give us a little more info now after reading the above we may be able to narrow it down

 

John T

[nena lynn]

It is the pedestal, as the amp reading across the posts read 120 instead of 240, so I'll get campground camp people to check it out.Thanks all.

[Dale P]

You measured VOLTS and not AMPS.

 

In measuring you measured from Hot to Hot, correct ? Or how did you measure it?.

[oldjohnt]

nena lynn, you're welcome, thanks for the feedback. Sounds like a good plan to have the park check it out. Indeed, if you're at a parks 120/240 volt 4 wire 50 amp receptacle (NO 50/30 amp dog bone adapters in use !!!) if there's 120 VAC L1 to L2 its the parks power pedestal or distribution problem. Of course, a good proper 50 amp 4 wire outlet still measures 120 L1 OR L2 to Neutral or to Ground but should be 240 L1 to L2..........

 

John T