need help understanding shore power and breaker box

BRUISER · July 30, 2012, 06:05:31 AM

ok here I am confused and need some help..

my Bus has a 50 amp power cord that I plug in at campsites and have never had issues with it.. well yesterday at home I ran the bus plug into my shop and then added a 30 amp adapter and a 20 amp adapter so I could plug bus into standard outlet in shop.

when I went into RV the front A/C does not turn on and a few outlets have no power.. but the back A/C works.. I pulled open breaker box and nothing is disconnected our loose..

what I am trying to figure out is 2 parts.. 1: when using a 20 amp plus will only part of the bus have power? 2: when we plug bus into 50AMP is it actually 110V or 240V?

thanks for any help?

BRUISER · July 30, 2012, 06:05:50 AM

the breaker question is has anyone used this type box in an RV/Bus?

it is different then my house one so I am a little confused with it and how it is wired

robertglines1 · July 30, 2012, 06:16:31 AM

Yes to explain simple with the 50 amp plug in you are bringing in two 120 volt legs from your power source and dividing them inside the pictured breaker box. the 30 amp adapter is eliminating one of your supply sides so one half of your box is dead. there are proper adapters available that will take care of that problem for you. Bob

thomasinnv · July 30, 2012, 06:51:58 AM

I think Bob pretty much covered it, but in case it wasn't clear enough...the breaker box is not the problem. Your 50-30 adapter is the culprit. Most 50-30 adapters take the single 120 hot input and supply that power to BOTH legs of the 50 amp chord/box. Your adapter is either home made and wired incorrectly, or it is the wrong kind. There are a few 50-30 adapters out there that only supply power to one leg of the 50. You have to be careful when buying an adapter.

Len Silva · July 30, 2012, 07:04:19 AM

Bob is correct in that the 50-30 adapter you have is not connecting both legs together as most do.

However, you have opened yourself up to a world of static from the board, including me, by posting the pictures of your breaker box.

First and foremost, extension cords are not acceptable for permanent wiring. I cannot stress that enough. I know it is done but I would not sleep one night in a bus so wired and it would be an absolute deal breaker if I were looking at a used bus to purchase.

Second, you need a separate ground bar for that breaker panel. It looks like it is wired for 240, though I cannot tell exactly where the white lead from the main cable is connected. If it is connected to the right side line in, then it looks like it's 240 but you only have a three wire cable. Hard to tell from the picture but the cable looks like 10 ga. That would be appropriate for a 30 amp/120 volt service, but it is wired wrong.

There are many other issues that I see. Suffice it to say that I think you need more advice on wiring than you can get from a board like this one.

Len

robertglines1 · July 30, 2012, 09:41:47 AM

???is that a 30 amp power cord with a 50 amp plug in on it? do you have a empty spade on the part you plug into the power supply. ?? if so please let us know and we can help. Bob there is not enough wires and they are to small for a 50 amp cord. shows I should have paid more attention to the picture. The extension cords you are using for wiring are probably 16ga and should not have more than a 15 amp breaker on them. This is not a lecture. a hair dryer pulls 2400 watts or close to 20 amps could fry(burn that cord) A ac on start up (0ne) could pull 18 amps 14 amps running. put anything else on same circuit=trouble. your box is ok. power feed to it needs attention and check breaker size and adjust to wire size. lets start there and walk thru it. a seperate ground outside box is a must. use search function in blue area above to help answer or help ask questions. Please do ask more questions. Others have same questions and people more knowledgeable than I will help also. No dumb question except one not ask. Bob

belfert · July 30, 2012, 10:04:23 AM

I'm wondering if that bus doesn't have more than one breaker panel. I have two breaker panels. One is inverter only and the other is shore power/generator only. The shore panel has a 30 amp feed to the inverter and then the inverter passes power to the inverter panel.

BRUISER · July 30, 2012, 10:47:43 AM

all good info..

as for the wiring etc.. this is how the bus was when I bought it.. heck I did not even know I could get in behind the cabinet to get to all this stuff ( I figured that out yesterday )

here is how my wiring goes..

50 amp cord into a junction box under bus ( I will get a picture tonight ) then out other side up into breaker box. 3 wires all hooked up.. Green, White and Black.. then all same colors go to an item.. like my front A/C has Green,white, black all hooked up..

I do understand what you are saying about the 50 to 30adapter and how it is only providing power to one side, that does make sense.. I also understand what you are saying about the cord wiring.. so I guess I need to look into see how hard it is gonna be to replace all the orange wiring..

as for opening up a can.. does not bother me I like to learn

BRUISER · July 30, 2012, 10:52:20 AM

Quote from: Len Silva on July 30, 2012, 07:04:19 AM
First and foremost, extension cords are not acceptable for permanent wiring. I cannot stress that enough. I know it is done but I would not sleep one night in a bus so wired and it would be an absolute deal breaker if I were looking at a used bus to purchase.
I will look into how hard it will be to pull new wires asap

Second, you need a separate ground bar for that breaker panel. It looks like it is wired for 240, though I cannot tell exactly where the white lead from the main cable is connected. If it is connected to the right side line in, then it looks like it's 240 but you only have a three wire cable. Hard to tell from the picture but the cable looks like 10 ga. That would be appropriate for a 30 amp/120 volt service, but it is wired wrong.

it does have a separate ground bar.. it is on the right side, hard to see in picture.

There are many other issues that I see. Suffice it to say that I think you need more advice on wiring than you can get from a board like this one.

this is the way the bus came I did not wire this

Len

robertglines1 · July 30, 2012, 10:55:59 AM

That orange cord should be marked as to wire size. could adjust breaker size to match wire size. I just read your complete bus project posting and do understand how your bus was built by previous owner a little more now. Bob. Not a aw shoot now just maybe adjust for future.

BRUISER · July 30, 2012, 10:56:51 AM

Quote from: robertglines1 on July 30, 2012, 09:41:47 AM
???is that a 30 amp power cord with a 50 amp plug in on it? do you have a empty spade on the part you plug into the power supply. ?? if so please let us know and we can help.
not sure what you mean? are you saying there should be 3 or 4 connctors on the plug side? I am pretty sure there are only 3.

Bob there is not enough wires and they are to small for a 50 amp cord. shows I should have paid more attention to the picture. The extension cords you are using for wiring are probably 16ga and should not have more than a 15 amp breaker on them. This is not a lecture. a hair dryer pulls 2400 watts or close to 20 amps could fry(burn that cord) A ac on start up (0ne) could pull 18 amps 14 amps running. put anything else on same circuit=trouble. your box is ok. power feed to it needs attention and check breaker size and adjust to wire size. lets start there and walk thru it. a seperate ground outside box is a must. use search function in blue area above to help answer or help ask questions. Please do ask more questions. Others have same questions and people more knowledgeable than I will help also. No dumb question except one not ask. Bob

BRUISER · July 30, 2012, 11:03:00 AM

Quote from: robertglines1 on July 30, 2012, 10:55:59 AM
That orange cord should be marked as to wire size. could adjust breaker size to match wire size. I just read your complete bus project posting and do understand how your bus was built by previous owner a little more now. Bob. Not a aw shoot now just maybe adjust for future.

I will look tonight and see if the orange or black wires actually have anything written on them

Sean · July 30, 2012, 01:08:37 PM

I just noticed this exact same thread is on both boards. Here was my reply on the other one, which repeats some of what is said above:

Quote from: Sean on July 30, 2012, 11:42:30 AM
Aaaaaaack!!!

I would not plug that coach into anything without a complete re-wire. It is a death trap.

For starters, the circuits have been run with junior hard service cord (SJ) or worse. Not only against the law, but highly dangerous -- a fire waiting to happen. These all need to be replaced with NM, AC, MC, or conduit. Even the main feed is SO, and appears undersized as well.

Second, I don't see even a single ground wire connected. Worse than just disconnected is that they are loose in the box, where they can come into contact with a 120v source, thus energizing an appliance frame.

Third, and this is probably the source of your apparent lack of power, this is a 120/240-volt split phase panel, but is being fed with three-wire SO. I can't tell from the photo whether you've got straight 120 coming in with hot, neutral, and ground properly colored, or if someone jury-rigged 240 on the wrong colors. Something is amiss in either case, because if it is fed straight 120, I don't see the correct jumper to gang that 120 onto both buss-bars.

Sorting this out will require a good voltmeter, ohmeter, time, patience, and a thorough understanding of split-phase electrical systems. I strongly recommend you do not connect this panel to any power source until it has been corrected, tested, and documented.

FWIW.

The other parts of your question have been answered many times here -- lots of detailed information in the archives. The short answer is that 50-amp RV service is 120/240-volt split phase, capable of 12,000 watts. 30-amp, 20-amp, and 15-amp service are straight 120, capable of 3600, 2400, and 1800 watts, respectively. Adapters from the smaller services to 50-amp generally put the single 120-volt power source on both legs, so everything is energized, but you are still limited to the lower number of watts. 240-volt appliances will not work when the same source is on both legs.

-Sean
http://OurOdyssey.BlogSpot.com

On closer inspection it now appears to me that the green wire from the incoming feed is carrying the second hot leg. In addition to the huge problem of the color coding being incorrect, a life safety hazard (anyone working on electricity will expect the green wire to be grounded, not carrying 240VAC), this means there is no independent connection to either the shore ground or the shore neutral, meaning one or the other is disconnected, or they are bridged someplace, either of which can be deadly. I will reiterate what I said above -- I would not plug this coach in until this is all sorted out and corrected.

-Sean
http://OurOdyssey.BlogSpot.com

TomC · July 30, 2012, 01:17:13 PM

OMG! Did a child wire this up? As Sean said DO NOT use this system that is wired without ground of any kind.
A 4 wire cable bringing in the power from the pole should be used to obtain grounding. Good Luck, TomC

BRUISER · July 30, 2012, 01:48:39 PM

Quote from: Sean on July 30, 2012, 01:08:37 PM
I just noticed this exact same thread is on both boards. Here was my reply on the other one, which repeats some of what is said above:

Quote from: Sean on July 30, 2012, 11:42:30 AM
Aaaaaaack!!!

I would not plug that coach into anything without a complete re-wire. It is a death trap.

For starters, the circuits have been run with junior hard service cord (SJ) or worse. Not only against the law, but highly dangerous -- a fire waiting to happen. These all need to be replaced with NM, AC, MC, or conduit. Even the main feed is SO, and appears undersized as well.

Second, I don't see even a single ground wire connected. Worse than just disconnected is that they are loose in the box, where they can come into contact with a 120v source, thus energizing an appliance frame.

Third, and this is probably the source of your apparent lack of power, this is a 120/240-volt split phase panel, but is being fed with three-wire SO. I can't tell from the photo whether you've got straight 120 coming in with hot, neutral, and ground properly colored, or if someone jury-rigged 240 on the wrong colors. Something is amiss in either case, because if it is fed straight 120, I don't see the correct jumper to gang that 120 onto both buss-bars.

Sorting this out will require a good voltmeter, ohmeter, time, patience, and a thorough understanding of split-phase electrical systems. I strongly recommend you do not connect this panel to any power source until it has been corrected, tested, and documented.

FWIW.

The other parts of your question have been answered many times here -- lots of detailed information in the archives. The short answer is that 50-amp RV service is 120/240-volt split phase, capable of 12,000 watts. 30-amp, 20-amp, and 15-amp service are straight 120, capable of 3600, 2400, and 1800 watts, respectively. Adapters from the smaller services to 50-amp generally put the single 120-volt power source on both legs, so everything is energized, but you are still limited to the lower number of watts. 240-volt appliances will not work when the same source is on both legs.

-Sean
http://OurOdyssey.BlogSpot.com

On closer inspection it now appears to me that the green wire from the incoming feed is carrying the second hot leg. In addition to the huge problem of the color coding being incorrect, a life safety hazard (anyone working on electricity will expect the green wire to be grounded, not carrying 240VAC), this means there is no independent connection to either the shore ground or the shore neutral, meaning one or the other is disconnected, or they are bridged someplace, either of which can be deadly. I will reiterate what I said above -- I would not plug this coach in until this is all sorted out and corrected.

-Sean
http://OurOdyssey.BlogSpot.com

so let me ask this question..

if the orange wires were correctly wired with correct type of wire and you found the green wires coming from the outlets not grounded what would you do with them? how would you terminate them and to what?

also since it looks like my hot wires are green and black and white is ground in the wire coming from shore power? how would you correct that? I saw mentioned that it should have a 4 wire not 3 wire shore power cord? where would the 4th wire go? to what?