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Re: Shore Power adapter, 240v to 120v?

PostPosted: Mon Oct 19, 2020 10:30 pm
by Karebru
OK. Here is my plan...
The only thing I'm converting is the plug pattern. (and adding a ground)
I have a 30 amp, 3 wire dryer circuit. I plan to replace the 3-prong receptacle with a 4-prong 50 amp receptacle, and to connect the existing ground wire that is already in the box. (10/3 Romex + ground) I will replace the dryer cord to match. (It will still be a 30 amp/240 volt circuit. I'm not changing the breaker.) This allows me to plug in a commonly used, '50 amp/240 volt to 30 amp' RV adapter and get what I need. It also upgrades my dryer circuit by adding the ground. (I'll need to make sure the ground wire is connected to the bus in the house panel.)

Image

I understand that bonding the frame to the AC ground doesn't ground the system. The ground comes from a shore power connection. I don't plan to use a generator. I've grown to hate the sound after several hurricanes.

Re: Shore Power adapter, 240v to 120v?

PostPosted: Tue Oct 20, 2020 5:59 am
by GTS225
OK.....sidebar: I feel the need to nitpick, or educate a little here, due to Scottie's incorrect posting.

troubleScottie wrote:It is made up of two circuits about 180 degrees or there about out of phase with each other which is how the power comes to the house.


Not quite correct. The phases are actually 120 degrees separated, so that three-phase power can be generated from a single generator. This opens up a whole 'nother discussion, so I'll not go there at this time.

troublescottie wrote:In a typical house, half the appliances are connected to one circuit, half to the other. This is visible in the 2 rows of breakers. One side is one, one is the other.


Scottie; Who taught you that? Have you ever had the plastic covers off of the inside of a breaker panel? If it's a conclusion on your part, from visual clues in a breaker panel, it's incorrect. Sure, the supply wires come in the top, to the left and right of center, (that's industry standard, and NEC regulation), but that's where the visual stops. Actually, the busses that the breakers clip to alternate vertically and from from side-to-side. That way, when you plug in a 2-pole breaker, (either left side or right), the load of the 240V appliance gets automatically balanced across the two "hot" lines.

Just to show what I mean, here's a google-found pic of the busses in a panel.
https://www.google.com/imgres?imgurl=ht ... egUIARC5Ag
Now, if you have a breaker panel that has it's left side hot buss supplying only the left side breakers, and right supplying right, scrap it. It was manufactured incorrectly, and doesn't meet code, anywhere in the U.S.

Just a little learnin', from a retired industrial electrician.....Roger

Re: Shore Power adapter, 240v to 120v?

PostPosted: Tue Oct 20, 2020 9:14 am
by hankaye
Howdy All;

As usual, I tend to stay away from electrical advise items here in the forum.
However, I input this, a list of free articles from a guy that IS an electrical Expert;
First here's his resume;
https://www.rvtravel.com/mike-sokols-qu ... al-expert/
Here's the list of articles;
https://www.rvtravel.com/category/rv-el ... ewsletter/

hank

Re: Shore Power adapter, 240v to 120v?

PostPosted: Tue Oct 20, 2020 9:53 am
by Karebru
hankaye wrote:Howdy All;

As usual, I tend to stay away from electrical advise items...

hank

I can see why. :?

Re: Shore Power adapter, 240v to 120v?

PostPosted: Tue Oct 20, 2020 3:52 pm
by MtnDon
Karebru wrote:OK. .............. (I'll need to make sure the ground wire is connected to the bus in the house panel.)



Do that before anything else.

Re: Shore Power adapter, 240v to 120v?

PostPosted: Fri Oct 23, 2020 8:41 am
by ZColorado
Karebru wrote: This allows me to plug in a commonly used, '50 amp/240 volt to 30 amp' RV adapter


You really should just skip all the adaptors and use a 50amp RV to the new 30a dryer circuit you have since you are updating the dryer circuit to 4 conductor anyways.

Re: Shore Power adapter, 240v to 120v?

PostPosted: Fri Oct 23, 2020 10:44 pm
by Karebru
ZColorado wrote:
Karebru wrote: This allows me to plug in a commonly used, '50 amp/240 volt to 30 amp' RV adapter


You really should just skip all the adaptors and use a 50amp RV to the new 30a dryer circuit you have since you are updating the dryer circuit to 4 conductor anyways.

Sorry. Ya lost me there. :scratchthinking:

My camper is 30 amp/120 volt. The dryer receptacle WAS un-grounded 30 amp/240 volt. I replaced the 30 amp receptacle ONLY with a 50 amp receptacle, so that the male plug on the above pictured adapter will fit. I did not change the 30 amp breaker. (I also hooked up the existing ground wire, and put a range cord on my dryer so that I can plug it in.)
The adapter... "pigtail"..."dog bone"... is needed to drop one 120 volt leg and gives me a grounded, 30 amp/ 120 volt female outlet to plug my camper cord in to.

I triple checked everything as I went along, with a voltage meter before plugging it in to the camper. ...No problems.