Difference Between 30 and 50 Amp Service

[Fred Mc]

What is the difference between a 30 amp service and 50 amp?

Do older Rvs also have 15 amp service?

Thx,

Fred

[TomC]

30amp is a 3 prong plug with positive, neutral and ground producing 30amps of 120vac. 50amp plug is a 4 prong plug with positive A, positive B, neutral and ground producing 50amps of 120vac from both positive A and positive B, but phased 180 degrees off-hence you only need one neutral. So with two 50 amp supplies, you actually have 100amps available.
On my bus, I only use one of the positives for straight 50amps at 120vac-hence I don't have to worry about balancing the loads out since all my bus is wired straight 120vac. Good Luck, TomC

[bevans6]

What Tom said...    I've had some RV's from the 1970's and they had the same standard 30 amp cord as we have today.  Pedestals almost always have a 15 or 20 amp receptacle for a standard three prong plug, though.  The other difference is in the cost of the cord - a 30 amp cord uses three conductor 10 gauge wire, while a 50 amp service uses considerably (like 3X) more expensive 4 conductor 6 gauge cable, which is physically around twice as heavy and bulky.

[Fred Mc]

So if you have a 50 amp chord how do you plug into a campground that only has a 30 amp service. Is there an adapter to go from 30 to 50 amps or do you have 2 separate chords- one for 30 and the other for 50 amps.

[edvanland]

Yes just buy the adaptor at Walmart, camping world or on line.

[bevans6]

An adaptor will either put the 30 amps on both legs of the 50 amp cord, or will only power up one leg with all 30 amps.  That means balancing will be an issue, any 240 volt appliances on the coach won't work, and a coach designed to actually use and need more than 30 amps will be blowing breakers or limited in functionality.  Like only one air conditioner instead of two or three, etc.

[Fred Mc]

Do camp sights charge more for 50 than 30 amps? If they do can you use your 30 amp adapter to get the cheaper rate?

Thx

Fred

[luvrbus]

Do camp sights charge more for 50 than 30 amps? If they do can you use your 30 amp adapter to get the cheaper rate?

Thx

Fred

Most campground do charge more for 50 Amp service lol they know why it is 50 amps 

[silversport]

Yes just buy the adaptor at Walmart, camping world or on line.

Or make your own.

[eagle19952]

The best adapters do not involve wire.

[chessie4905]

They overheat and deteriorate over time just like the cords, mostly from overloading. The main thing is to inspect them all frequently and replace when showing signs of distress. Also don't try to draw more amps than the smallest amp rating adapter or cord. There was one on facebook that a guy caught on fire. Also keep in mind that low campground voltages cause increased amperage draw from your appliances.

[eagle19952]

They overheat and deteriorate over time just like the cords, mostly from overloading. The main thing is to inspect them all frequently and replace when showing signs of distress. Also don't try to draw more amps than the smallest amp rating adapter or cord. There was one on facebook that a guy caught on fire. Also keep in mind that low campground voltages cause increased amperage draw from your appliances.

in any wiring the connections (screws/landings) are the point of cause.
the adapters have none. makes them better

[bigred]

The best adapters do not involve wire.

If you can find an electrical distributor that stocks Midwest Electrical Products you should be able to find any kind of adapter you would need .Used to be in the four dollar range probably twice that now!!

[bobofthenorth]

They overheat and deteriorate over time just like the cords, mostly from overloading.

Exactly and they don't even have to be overloaded.  In fact unless the breaker they're on is defective they technically "can't" be overloaded.  I've melted the little cubes and the pigtails.  Pull a steady 30 amps on a hot day and you'll melt them too.  They're a consumable and a fire risk.  Wore out plugs on a camp pedestal and low voltage brownouts from too many ACs running on a marginal campground service both contribute to higher amp draws with attendant higher heat.  Over time these adapters just inevitably need to be replaced.