Grand Design 50 Amp Electric Scheme

[wjpatter]

I'm looking for information about access and what the switch panel looks like on the back side. I have shined a like into the crawl space but have never ventured into the abyss. Is accessing the back of the panel through the crawl space or does the panel pull out?? Does anyone have a picture of what that part of the world looks like?

I think I've seen a thread by [MENTION=6602]BjornF16[/MENTION] in 2017 that did what I'm thinking about doing, which is run 1/2 the coach off Shore power/Inverter power using a transfer switch and the other 1/2 unpowered without shore power. I think I read that, like a house, 1/2 the circuits are on one 120 VAC line and the other half on the second AC line and they are organized left and right of the main breakers.

Any guidance on how to get into the wiring will be appreciated.

 

[Second Chance]

The wires all come through access ports on the back of the main power panel - there is not much to be gained by getting to the back of the plastic "box." The whole power panel can be unscrewed and pulled out to the front of the cabinet, though.

The 50 amp "shore" power is in two legs and there are two 50 amp breakers at the center of the power panel. You are correct in that the left and right sides of the power panel are two different busses supplied by their respective 50 amp breakers. The 15 and 20 amp breakers could be rearranged to put the important circuits on one side for supply by an inverter - you would need to make sure that the current demands remain balanced so as not to overload one side of system.

Rob

 

[CoChris-MGRV]

I'm looking for information about access and what the switch panel looks like on the back side. I have shined a like into the crawl space but have never ventured into the abyss. Is accessing the back of the panel through the crawl space or does the panel pull out?? Does anyone have a picture of what that part of the world looks like?

I think I've seen a thread by @BjornF16 in 2017 that did what I'm thinking about doing, which is run 1/2 the coach off Shore power/Inverter power using a transfer switch and the other 1/2 unpowered without shore power. I think I read that, like a house, 1/2 the circuits are on one 120 VAC line and the other half on the second AC line and they are organized left and right of the main breakers.

Any guidance on how to get into the wiring will be appreciated.

View attachment 33768

Exactly what Rob @Second Chance said above. All info is spot on.

Access to the rear of the panel will depend greatly on your trailer. On our Solitude, it is basically it is not accessible. Remove the cover from the front and you have access to all the wiring. Here is a picture of the panel in our trailer. Yours maybe different.



Pictures are rotated (again ), but (in the pictures) the 12V DC (battery) circuits are on the left and the 120v AC circuits are on the right 2/3 of the box. Hope this helps.

Chris

 

[traveldawg]

I'm looking for information about access and what the switch panel looks like on the back side. I have shined a like into the crawl space but have never ventured into the abyss. Is accessing the back of the panel through the crawl space or does the panel pull out?? Does anyone have a picture of what that part of the world looks like?

I think I've seen a thread by [MENTION=6602]BjornF16[/MENTION] in 2017 that did what I'm thinking about doing, which is run 1/2 the coach off Shore power/Inverter power using a transfer switch and the other 1/2 unpowered without shore power. I think I read that, like a house, 1/2 the circuits are on one 120 VAC line and the other half on the second AC line and they are organized left and right of the main breakers.

Any guidance on how to get into the wiring will be appreciated.

View attachment 33768

I'm going to suggest that if you go through all this work that you run BOTH legs off of shore power, but run SOME circuits through an inverter (or inverter/converter). That way you are not always 'battery dependent' on some circuits.

To do this: run an appropriate sized circuit to your inverter from your panel, run the output of the inverter to a separate panel (sub-panel) for the circuits you want to run on battery power when you are not connected to shore power. When you remove the breakers from your existing panel for use in your sub-panel you will free up room for the new breaker that would go to your inverter.

fwiw.... that's how the major motorhome manufacturers do (and probably the higher end trailers). Most of the time manufacturers who do this accomplish it with a single breaker panel designed for this; us poor bums who do it ourselves resort to a separate sub panel.

ph - one more thing about run "half-and-half"..... your circuits are divided between both legs to balance the loads. for example: one AC is on one leg, the second AC on another; the water heater is on one leg, the microwave on the other (ditto for sharing between fireplace, converter, etc. So if you just simply apply the "half-and-half" scheme then you are likely to have some circuits that you just won't/can't run via inverter (i.e. - air conditioning).

just thought I'd throw this option out there for consideration.


Here is what I did.

You don't really need a transfer switch doing things this way either. Of course, a lot of this depends on the space you have in your rig.

 

[wjpatter]

The wires all come through access ports on the back of the main power panel - there is not much to be gained by getting to the back of the plastic "box." The whole power panel can be unscrewed and pulled out to the front of the cabinet, though.

The 50 amp "shore" power is in two legs and there are two 50 amp breakers at the center of the power panel. You are correct in that the left and right sides of the power panel are two different busses supplied by their respective 50 amp breakers. The 15 and 20 amp breakers could be rearranged to put the important circuits on one side for supply by an inverter - you would need to make sure that the current demands remain balanced so as not to overload one side of system.

Rob

Hopefully, I won't need to rearrange any of the breakers. My motivation is to activate the rear coach power outlets, specifically power to the outside refrigerator. I had planned to add a second 400 watt inverter and route lines to specifically power the single outlet so that I can keep the refrigerator powered while I drive. After looking at some other DYIs, I'm considering interrupting one of the lines from shore power and using my existing 2000 w inverter with a transfer switch to power the living/kitchen area of the coach. I have to figure out which breaker controls the outlets in the rear. Breaking into the power path from shore power is doable creates a bit of pucker factor. Alternatively, if I can isolate the refrigerator outlet to a single breaker and also understand what else I might be powering would be a simpler solution.

So what you are telling me is the back of the switch panel is uninteresting. I can access line 1 & 2 (shore power) from the front. How do the power lines for internal wiring to the coach exit the box?

 

[wjpatter]

Exactly what Rob @Second Chance said above. All info is spot on.

Access to the rear of the panel will depend greatly on your trailer. On our Solitude, it is basically it is not accessible. Remove the cover from the front and you have access to all the wiring. Here is a picture of the panel in our trailer. Yours maybe different.

View attachment 33773 View attachment 33774

Pictures are rotated (again ), but (in the pictures) the 12V DC (battery) circuits are on the left and the 120v AC circuits are on the right 2/3 of the box. Hope this helps.

Chris

Worth a 1000 word. Helps a lot. Thanks

 

[wjpatter]

I'm going to suggest that if you go through all this work that you run BOTH legs off of shore power, but run SOME circuits through an inverter (or inverter/converter). That way you are not always 'battery dependent' on some circuits.

To do this: run an appropriate sized circuit to your inverter from your panel, run the output of the inverter to a separate panel (sub-panel) for the circuits you want to run on battery power when you are not connected to shore power. When you remove the breakers from your existing panel for use in your sub-panel you will free up room for the new breaker that would go to your inverter.

fwiw.... that's how the major motorhome manufacturers do (and probably the higher end trailers). Most of the time manufacturers who do this accomplish it with a single breaker panel designed for this; us poor bums who do it ourselves resort to a separate sub panel.

ph - one more thing about run "half-and-half"..... your circuits are divided between both legs to balance the loads. for example: one AC is on one leg, the second AC on another; the water heater is on one leg, the microwave on the other (ditto for sharing between fireplace, converter, etc. So if you just simply apply the "half-and-half" scheme then you are likely to have some circuits that you just won't/can't run via inverter (i.e. - air conditioning).

just thought I'd throw this option out there for consideration.


Here is what I did.

You don't really need a transfer switch doing things this way either. Of course, a lot of this depends on the space you have in your rig.

Good input from this forum. I was only considering using the 50 L1 because I thought it would be easier. After looking in the box and doing some isolation tests, my external refrigerator is on the same line as the internal refrigerator and is easy to isolate. Running both refrigerators off AC while I drive will be a nice advantage.

You pose an interesting concept of running some circuits continuously off of the inverter. It certainly would have some real advantages. I verified that the 2 refrigerators, tv and one outlet runs off the single breaker. Hopefully, that is all. The outlet is normally used for the Keurig which peaks at 1380 watts on boil. Deliver and standby modes are much lower so that running from the inverter would be ok. The wild card is the microwave. If it is on that same circuit, it would be a no go. That device is a pig, almost at the max rating for my 2000w inverter.

I looked quickly at your setup and understand the secondary panel. Why a lithium converter and how are you using the transfer capability of the Xantrex XC2000 inverter/converter?

 

[traveldawg]

Good input from this forum. I was only considering using the 50 L1 because I thought it would be easier. After looking in the box and doing some isolation tests, my external refrigerator is on the same line as the internal refrigerator and is easy to isolate. Running both refrigerators off AC while I drive will be a nice advantage.

You pose an interesting concept of running some circuits continuously off of the inverter. It certainly would have some real advantages. I verified that the 2 refrigerators, tv and one outlet runs off the single breaker. Hopefully, that is all. The outlet is normally used for the Keurig which peaks at 1380 watts on boil. Deliver and standby modes are much lower so that running from the inverter would be ok. The wild card is the microwave. If it is on that same circuit, it would be a no go. That device is a pig, almost at the max rating for my 2000w inverter.

I looked quickly at your setup and understand the secondary panel. Why a lithium converter and how are you using the transfer capability of the Xantrex XC2000 inverter/converter?

The Xantrex convert can regulate wet, AGM, and Lithium batteries (and a few others). Mine is set for AGM.

The Xantrex has an internal transfer switch. So when it doesn't detect incoming 120v it automatically switches over. It happens so quick sometimes I don't even notice.

Mostly it is my refrigerator and electric outlets on the inverter except for the water and dryer outlets and the one for the dishwasher (which I don't have anyway).

 

[wjpatter]

The Xantrex convert can regulate wet, AGM, and Lithium batteries (and a few others). Mine is set for AGM.

The Xantrex has an internal transfer switch. So when it doesn't detect incoming 120v it automatically switches over. It happens so quick sometimes I don't even notice.

Mostly it is my refrigerator and electric outlets on the inverter except for the water and dryer outlets and the one for the dishwasher (which I don't have anyway).

I remember reading this thread when I was looking at batteries and inverters. Breaking into the switch panel looked more complicated that what I wanted to tackle. Looking at it now, the real hard part will be running line from my inverter in the front compartment to the switch panel. I'll probably mount the transfer switch in the front compartment also, just to have ready access if it fails. Did you pull 120 VAC directly off L1/L2 coming in? This solves my inverter logistical problems also. Before I decided to power the external refrig, the only time my inverter was used was stationary and I powered using the shore power plug. That required me to move the couch to turn off a number of breakers like convert, AC's, hot water tank, and fire place. More was off than on. What secondary panel did you use?

 

[traveldawg]

I remember reading this thread when I was looking at batteries and inverters. Breaking into the switch panel looked more complicated that what I wanted to tackle. Looking at it now, the real hard part will be running line from my inverter in the front compartment to the switch panel. I'll probably mount the transfer switch in the front compartment also, just to have ready access if it fails. Did you pull 120 VAC directly off L1/L2 coming in? This solves my inverter logistical problems also. Before I decided to power the external refrig, the only time my inverter was used was stationary and I powered using the shore power plug. That required me to move the couch to turn off a number of breakers like convert, AC's, hot water tank, and fire place. More was off than on. What secondary panel did you use?

Before I get into how/why/what I did, let's back-up a bit.....

What is you want to do? It looks like you just want 2 refrigerators on AC when driving. I have to admit I am not familiar with the AC/DC/Gas refrigerators as I've had a residential refrigerator the last 2 RVs.

Never mind about how to do it right now, I'm just a bit confused on the overall "mission" here. I don't want to propose an over complicated set-up if it is just one circuit you need on an inverter.

Thanks....

 

[wjpatter]

Before I get into how/why/what I did, let's back-up a bit.....

What is you want to do? It looks like you just want 2 refrigerators on AC when driving. I have to admit I am not familiar with the AC/DC/Gas refrigerators as I've had a residential refrigerator the last 2 RVs.

Never mind about how to do it right now, I'm just a bit confused on the overall "mission" here. I don't want to propose an over complicated set-up if it is just one circuit you need on an inverter.

Thanks....

Powering the external refrigerator while traveling was the prime objective but the degree of difficulty of either running an AC line to it or a heavy DC line to power a 400 w inverter locally, is high. Actually higher than what you have implemented with the secondary breaker box. The functionality of the Xantrex is over kill for my needs but it explains questions that I've always had. My Holiday Rambler motor home had an inverted that seamlessly ran the coffee maker whether I was on shore power or on battery. When Oliver installed the inverter in my 17' travel trailer, they wired dedicated outlets. It worked but I had to unplug the coffee maker and move to the inverter outlet. I didn't understand it at the time but I think I do now. Regarding a complicated setup, I can isolated a single breaker and power the external refrigerator. No problem. For free, I also power the TV and coffee maker outlet off the same change. As a bonus, I get the refrigerator that allow me to run AC mode while traveling. I've already made the change to the truck to supply 50 amps to a DC/DC converter to charger the batteries while I tow, so running the inverter fits well within the design. Now that I've lifted the hood to see how the switch panel operates and for a nickel more, I think can isolate two additional breaker and have a hands free inverter system for my simple needs. As I mentioned, the biggest wart in my current setup is that I have to drop the converter breaker, which is in the switch panel behind the couch. I have to turn the converter when I connect the coach to the inverter to eliminate the parasitic charge loop when I connect the extension cord to the 50 amp input power connector.

 

[traveldawg]

Powering the external refrigerator while traveling was the prime objective but the degree of difficulty of either running an AC line to it or a heavy DC line to power a 400 w inverter locally, is high. Actually higher than what you have implemented with the secondary breaker box. The functionality of the Xantrex is over kill for my needs but it explains questions that I've always had. My Holiday Rambler motor home had an inverted that seamlessly ran the coffee maker whether I was on shore power or on battery. When Oliver installed the inverter in my 17' travel trailer, they wired dedicated outlets. It worked but I had to unplug the coffee maker and move to the inverter outlet. I didn't understand it at the time but I think I do now. Regarding a complicated setup, I can isolated a single breaker and power the external refrigerator. No problem. For free, I also power the TV and coffee maker outlet off the same change. As a bonus, I get the refrigerator that allow me to run AC mode while traveling. I've already made the change to the truck to supply 50 amps to a DC/DC converter to charger the batteries while I tow, so running the inverter fits well within the design. Now that I've lifted the hood to see how the switch panel operates and for a nickel more, I think can isolate two additional breaker and have a hands free inverter system for my simple needs. As I mentioned, the biggest wart in my current setup is that I have to drop the converter breaker, which is in the switch panel behind the couch. I have to turn the converter when I connect the coach to the inverter to eliminate the parasitic charge loop when I connect the extension cord to the 50 amp input power connector.

OK. I get it.... Simple one circuit on an inverter for the external frig, TV and coffee maker. And, if you can, 2 more circuits for the other outlets.

I think for one circuit (and maybe 2 if within an inverter specs) you could just use one like a lot of the manufactures are using. This one has a built in transfer switch.

As soon as you get more complicated and want multiple circuits which draw more power I think you need to move away from that example and figure out how to power an inverter with one circuit (most likely a 30amp circuit) and then feed the inverter output back to the 1,2, or 3 circuits you want to power. That's where the sub panel comes in. I got mine at Lowes (or maybe Home Depot).

And then you will need to power the converter from a non-inverter circuit. On my rig the converter was already on it's own circuit, it sounds like yours shares a circuit with other things. So either you isolate the converter circuit or forget using an inverter output for the converter circuit (and what ever else is on it).

 

[wjpatter]

OK. I get it.... Simple one circuit on an inverter for the external frig, TV and coffee maker. And, if you can, 2 more circuits for the other outlets.

I think for one circuit (and maybe 2 if within an inverter specs) you could just use one like a lot of the manufactures are using. This one has a built in transfer switch.

As soon as you get more complicated and want multiple circuits which draw more power I think you need to move away from that example and figure out how to power an inverter with one circuit (most likely a 30amp circuit) and then feed the inverter output back to the 1,2, or 3 circuits you want to power. That's where the sub panel comes in. I got mine at Lowes (or maybe Home Depot).

And then you will need to power the converter from a non-inverter circuit. On my rig the converter was already on it's own circuit, it sounds like yours shares a circuit with other things. So either you isolate the converter circuit or forget using an inverter output for the converter circuit (and what ever else is on it).

Anything resistive or the AC's draw too much power. The microwave, by it's self, is near the limit of the inverter so that is take a bit or care to use. So it think it will look like this.

 

[traveldawg]

First, there should be an inverter in the circuit someplace for that to work (or I don't understand what the WFCO transfer switch entails. Do you already have an inverter? If not the just get one with a built in transfer switch.

Then that would work. But I don't see a Microwave running very well unless you have a bunch of batteries.

And I still think you should just use one of the circuits you move to the sub panel to feed 30amps to the transfer switch. It may only make a difference if you want to power off the inverter while there is still power to the RV (for maintenance or something like that I suppose).

 

[wjpatter]

First, there should be an inverter in the circuit someplace for that to work (or I don't understand what the WFCO transfer switch entails. Do you already have an inverter? If not the just get one with a built in transfer switch.

Then that would work. But I don't see a Microwave running very well unless you have a bunch of batteries.

And I still think you should just use one of the circuits you move to the sub panel to feed 30amps to the transfer switch. It may only make a difference if you want to power off the inverter while there is still power to the RV (for maintenance or something like that I suppose).

4 AGM Batteries power the 2000w inverter. The DC/DC Converter runs off the truck alternator or solar panels to pump 50 amp of charge current into the batteries. I'll move two breakers from the switch panel to isolate refrigerators, TV, microwave and all coach outlets. I'll insert a 30amp breaker in the hole created moving the circuits to power the sub panel. The only issue is how much confidence do I have with the WFCL transfer switch. If I bury it near the subpanel I only need to pull one power line from the front where the inverter is to the switch. If it fails, it becomes a major repair digging it out so I'm leaning toward keeping it exposed in the front compartment. I see the micro wave running 3 minutes at a time for pop corn or maybe 10 minutes to cook the dogs chicken, which happens maybe once a week.

 

[traveldawg]

Sounds like a good plan. I'd put the transfer switch where it is pretty easy to get to. Let us know how it works out.