30/50 amp question? First time connecting to shore power.

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30/50 amp question? First time connecting to shore power.

November 21, 2014, 08:38:12 am

Well we're taking Nelson out for his first camping weekend today, I booked a site at the state park down in SC. All systems seem to be good to go. I have not had it plugged into shore power yet and the campsite has a 30 amp service. I have both cables 50 and a 30. Is there anything I need to do when I plug in the first time?

Re: 30/50 amp question? First time connecting to shore power.

Reply #1 – November 21, 2014, 09:03:39 am

Does Nelson have two connections - a 30A and a 50A - or just one? Or do you have a "dog bone" adapter that lets you plug your 50A cord into a 30A outlet? I have only one 50A connection on my coach (and therefore one 50A power cord). When we are at a site with only 30A service I use an adapter that lets me plug my 50A cord into the 30A outlet.

Your coach should have an automatic transfer device (located under the bed, at the foot). I plug the cord into the coach, stretch it out to the pedestal, then plug in the Progressive Industries protection device, check that all is good, then plug the power cord into the PI device. I turn the breaker in the pedestal on when checking, then off while connecting, then back on again.

Re: 30/50 amp question? First time connecting to shore power.

Reply #2 – November 21, 2014, 09:52:20 am

If you don't have a protective device like David mentioned, it's a good idea to check the campground's outlet with a volt meter before plugging in your coach. e.g. If it is a 50 amp you should have around 120v on each of the hots and no voltage on the neutral and ground. There are lots of posts over at rv.net on how to do this. Also, it is a good practice to make sure the campground's breaker is off when you plug in. Once, connected, just switch the breaker on. In addition, you should have a polarity light somewhere (above the entry door?) that will alert you if you have a reversed polarity connection.
jor

Re: 30/50 amp question? First time connecting to shore power.

Reply #3 – November 21, 2014, 10:22:54 am

Suspect you have the dog-bone 30 to 50 amp adapter like most of us. I have 2 long 30 amp cables that still have to be plugged into the adapter. Small RV's may have just a 30 amp cable, but have never seen an RV with both. If the campsite has 50 amp use that as it supplies more power. With 30 amps you get 120v x 30 amps = 3600 watts, with 50 amps its 120 x 50 x 2 = 12,000 watts. The 50 amp connection has 2 120v legs, the voltage from leg to leg is 240 but from leg to neutral is 120. The dog-bone adapter is wired so that 120 is supplied to both legs when it is in use. So although the coach is plugged into 240; only 120v is used by the coach. This could be different on some large high end coaches but not on yours.

Re: 30/50 amp question? First time connecting to shore power.

Reply #4 – November 21, 2014, 10:38:02 am

"...but have never seen an RV with both." Many 'Birds are set up that way. I'm not sure what the logic was, but it seems to me that it just adds more complexity.

Re: 30/50 amp question? First time connecting to shore power.

Reply #5 – November 21, 2014, 12:16:42 pm

I have 2 power cords one is heavy for 50 amp the other is lighter for 30 amp.either one can plug into the receptacle on coach.

Re: 30/50 amp question? First time connecting to shore power.

Reply #6 – November 21, 2014, 01:31:11 pm

I have just the one 50-amp cord like David has and I use an adapter for 30-a connections. Seems to work fine.

If you are interested in the Progressive Industries 50-amp electrical management system like David uses (and several others, including me), the best price I've found is at Tweety's (http://tweetys.com/portable-50-amp-electrical-management-system.aspx). Don't confuse the EMS with a surge protector. I've used my PI EMS50 with a 30-to-50 amp adapter and it's worked fine.

You probably won't need it for your state park hook-up but you might want to consider it for future use. Or the built-in model.

You can get the 30-a to 50-a adapters at Walmart if you don't have one.

On edit, I thought I'd add that my coach, which was considered "entry level" (at over $200k in 1993!!!) has an interesting cable setup. The pedestal end has a typical 50-a 4-prong connector (male) but the coach end has a 3-prong connector. This confused me considerably when I first bought the coach as I kept looking for a 50-a 4-prong connection on the coach itself but there wasn't one; however there was a decal advising that the connection is 50-amp. And it is 50-amp but it's weird. At any rate the cord works fine with a 30-amp adapter or on 50-amp without an adapter. Or with the PI 50-amp EMS portable.

Have fun!

Craig

Re: 30/50 amp question? First time connecting to shore power.

Reply #7 – November 21, 2014, 02:53:45 pm

Quote from: stump – November 21, 2014, 12:16:42 pm

I have 2 power cords one is heavy for 50 amp the other is lighter for 30 amp.either one can plug into the receptacle on coach.

But they will not both plug into the campground post if it has only a 30 amp outlet. If the post has only a 50 amp outlet you will need a dog one to use the 30 amp cord. I usually always use the 30 amp cord hate dealing with that heavy 50 amp cord.

Roland

Re: 30/50 amp question? First time connecting to shore power.

Reply #8 – November 21, 2014, 03:32:10 pm

Most times a thirty amp connection is enough, however, if you are needing to use both A/C's at the same time the thirty amp will not be enough. If you are camping in Mohave the the temperature is 122 degrees in the shade then you need 50 amps ( but the old park we were at did not have it)!

Re: 30/50 amp question? First time connecting to shore power.

Reply #9 – November 21, 2014, 04:53:22 pm

Stump, if I understand you correctly, you have two different cords for your coach. Both have the same coach end, but one has three straight blades and one round one (that's the 50A cord) and one has two blades at and angle to each other and one round one (that's the 30A cord). Is that correct? If so, then that 30A cord functions as the dog bone adapters that many of us use. Yours is a simpler solution to a 50A coach and a 30A pedestal, although it costs you a few more pounds to carry.

Re: 30/50 amp question? First time connecting to shore power.

Reply #10 – November 21, 2014, 06:18:30 pm

I have both chords. When I need a 50amp service, I drag out the Boa- constrictor chord. I dont normally use it because it is only a temptation for some one to steal. Normally the 30 amp chord will handle it all and if it gets stolen I am out alot less money. Thanks and have a great day ---- Fritz

Re: 30/50 amp question? First time connecting to shore power.

Reply #11 – November 21, 2014, 06:33:42 pm

Quote from: stump – November 21, 2014, 08:38:12 am

Well we're taking Nelson out for his first camping weekend today, I booked a site at the state park down in SC. All systems seem to be good to go. I have not had it plugged into shore power yet and the campsite has a 30 amp service. I have both cables 50 and a 30. Is there anything I need to do when I plug in the first time?

Stump,Where in SC are you camping.? If you need anything,don't hesitate to contact me we are located in the Upstate area of SC near Landrum.

Hans

Re: 30/50 amp question? First time connecting to shore power.

Reply #12 – November 22, 2014, 08:46:28 am

Plugged into outlet everything is working. There is a silver metal box mounted just above and left if the bstterys it has a fan grill SD crern on it. I'm thinkin it has a relay inside it or a transformer. It hums pretty loud then quits kind of like what a battery charger would sound like. What does this do? Im sure it's not supposed to hum on and off. Also my zip dee awning Won't extend the lock dosnt want to release.

Re: 30/50 amp question? First time connecting to shore power.

Reply #13 – November 22, 2014, 08:50:43 am

Quote from: wa_desert_rat – November 21, 2014, 01:31:11 pm

On edit, I thought I'd add that my coach, which was considered "entry level" (at over $200k in 1993!!!) has an interesting cable setup. The pedestal end has a typical 50-a 4-prong connector (male) but the coach end has a 3-prong connector. This confused me considerably when I first bought the coach as I kept looking for a 50-a 4-prong connection on the coach itself but there wasn't one; however there was a decal advising that the connection is 50-amp. And it is 50-amp but it's weird. At any rate the cord works fine with a 30-amp adapter or on 50-amp without an adapter. Or with the PI 50-amp EMS portable.

Have fun!

Craig

Craig,
If you have the standard Marinco twist on plug on the coach end like the one pictured below, the 4th/ground pin is located on the metal band on the side.

Re: 30/50 amp question? First time connecting to shore power.

Reply #14 – November 22, 2014, 09:10:01 am

Quote from: stump – November 22, 2014, 08:46:28 am

... snip...Also my zip dee awning Won't extend the lock dosnt want to release.

I assume you are talking about the twisty thing locking the aluminum cover to the coach.
The locks at the ends have nothing to do with swinging down the awning.

I sometimes have to use a long scrub brush handle to wedge between the cover and the coach to push the cover into position for the regular tool to work.
hth

Re: 30/50 amp question? First time connecting to shore power.

Reply #15 – November 22, 2014, 11:48:18 am

Quote from: stump – November 22, 2014, 08:46:28 am

...There is a silver metal box mounted just above and left if the bstterys it has a fan grill SD crern on it. I'm thinkin it has a relay inside it or a transformer. It hums pretty loud then quits kind of like what a battery charger would sound like. What does this do?

Hard to tell without a photo as the PO might have changed out some components. But I can tell you what was on my coach originally: two "boxes" were mounted up there. On the left was the battery converter (ref "changer" vs "converter" discussion Converter vs. Inverter/Charger Upgrade ) suspended on four pieces of all thread from the ceiling. About in the center and ceiling mounted was main power transfer switch, to switch power from the shore to generator. I don't remember there being a fan on either of these and I have changed out both so I can't just look. I don't think I have ever seen a fan on a transfer switch since only relays with very little heat generation are inside. My new battery changer does have a fan and I think just about any charger will - unlike the old converter. My old transfer switch would buzz a lot from the relays when plugged and I could hear it quite well inside if it was quite out at all. My new transfer switch works differently in that the relay coils are only energized when the generator is running so it's completely silent when plugged in. Hope this helps.

Re: 30/50 amp question? First time connecting to shore power.

Reply #16 – November 22, 2014, 05:15:18 pm

John Fitz nailed it.it us suspended by threaded rod it hums and then gets louder thrn quiets down some.then gets louder.like it cycles.I have no internet to speak of snd using my phone here. Whatever this is does it's getting upgraded. I don't have enough signal yo post pic but it is to the left of another transfer box .

Re: 30/50 amp question? First time connecting to shore power.

Reply #17 – November 22, 2014, 05:23:44 pm

It looks like to me is that someone made up a 30 amp cord so they wouldn't have to lug the 50 amp cord around and that's why you have two cords.
I made up a 30 amp cord for my motor home using the 50 amp female plug. It works great. When you are at a place that has 50 amps use your 50 amp
cord and when you are at a campsite that only has 30 amps you can use the 30 amp cord or you can use the 50 amp cord with a 30 amp adapter.

Re: 30/50 amp question? First time connecting to shore power.

Reply #18 – November 22, 2014, 05:25:18 pm

Re: 30/50 amp question? First time connecting to shore power.

Reply #19 – November 23, 2014, 06:42:03 pm

This is the box that was humming loudly, Is this a battery charger? What would be a better device to use that dosn'y hum so loud? To the right of it is this black box.

Re: 30/50 amp question? First time connecting to shore power.

Reply #20 – November 23, 2014, 07:20:58 pm

Yes, that's the converter/charger. I pulled mine and bought a Progressive Industries smart charger with the pendant. I got a 45-amp version because my OEM device was 45-amp. You probably want something bigger. My 45-amp is about $150 at Amazon. The 60-amp is over $200. Be sure to get the "charge wizard".

Link to the 60-amp: Amazon.com: Progressive Dynamics (PD9260CV) 60 Amp Power Converter with Charge

There are other inverter/chargers out there and some might be even better than the PI unit.

Craig

As an Amazon Associate Foretravel Owners' Forum earns from qualifying purchases.

Re: 30/50 amp question? First time connecting to shore power.

Reply #21 – November 23, 2014, 07:25:33 pm

We replaced our old ones with newer ones, too, because one was buzzing loudly enough to be irritating and because they destroyed the batteries. As Craig said, there are lots of choices out there, so do some research and find the one that fits you best.

Re: 30/50 amp question? First time connecting to shore power.

Reply #22 – November 23, 2014, 10:40:25 pm

Yes, those are both OEM - looks identical to what my coach had in it. I see the converter does have a fan in it - I didn't remember that. In my opinion, the advantage of a modern 3 stage charger over the old converter is when you have to run the generator to recharge your batteries (i.e. boondocking). A 3 stage charger will do the same amount of charging in less time - so it will save you generator time. If you ever upgrade your inverter to a new unit most people go for an inverter/charger which will make your converter unnecessary. But I would just disconnect 120VAC from it and keep it there as a backup - always good to have some kind of charging capacity backup whether it be a portable Sears charger that most people have in their garage or a 23 year old converter.
I would keep the black transfer switch unless it's giving you problems.

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