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Old 05-22-2020, 10:03 PM   #1
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THOR #12189
Positioning an Inverter

I'm planning out a solar install. In my research, I have not come across anyone who explains where they placed things and why.

For instance, I read you should place the inverter close to the batteries to reduce line loss. My batteries are under the steps in the front of the coach and I have a nice void to place the inverter that's no more than 2-3ft away from the batteries. My fuse/breaker panel is in the rear under the bed. What about the run from the inverter to power panel? It plays into wire size. I found a calculator to help with voltage loss. My initial thought is locate everything up front in that void and run the inverter's 120v output back to the power panel. It's large enough to hold all the components and I have enough wall space to mount the monitoring and control panels. My concern is most all the outlets I use are located up front so, now I make that run all the way to the back to reach the power panel and send it all right back up front to use the outlets.

Is it best to locate the inverter somewhere in between to "split the loss", place it closer to one end or the other other to 'balance' the loss? Or just get it as close to the batteries as possible? See my dilemma?

If you have something I can read, I'd appreciate it. I'm not adverse to reading something for myself. I just need to find it.
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Old 05-22-2020, 10:41 PM   #2
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Quote:
Originally Posted by The_Breeze View Post
I'm planning out a solar install. In my research, I have not come across anyone who explains where they placed things and why.

For instance, I read you should place the inverter close to the batteries to reduce line loss. My batteries are under the steps in the front of the coach and I have a nice void to place the inverter that's no more than 2-3ft away from the batteries. My fuse/breaker panel is in the rear under the bed. What about the run from the inverter to power panel? It plays into wire size. I found a calculator to help with voltage loss. My initial thought is locate everything up front in that void and run the inverter's 120v output back to the power panel. It's large enough to hold all the components and I have enough wall space to mount the monitoring and control panels. My concern is most all the outlets I use are located up front so, now I make that run all the way to the back to reach the power panel and send it all right back up front to use the outlets.

Is it best to locate the inverter somewhere in between to "split the loss", place it closer to one end or the other other to 'balance' the loss? Or just get it as close to the batteries as possible? See my dilemma?

If you have something I can read, I'd appreciate it. I'm not adverse to reading something for myself. I just need to find it.
The voltage drop is much greater on the 12 volt side of things. No problem with the 120 side with that short of a distance.
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Old 05-22-2020, 10:54 PM   #3
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Agreed, the 12V DC current is at least 10 times the 120V AC current. And power loss is proportional to the square of the current. That's 100 times the loss for the same wire. Which is why the cables to the inverter are short and huge!
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Old 05-23-2020, 12:17 AM   #4
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My inverter is attached to the ceiling of the right front storage compartment. (My batteries are also under the steps)
Less than four feet between them.
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Old 05-23-2020, 12:29 AM   #5
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I added an inverter to the Gemini, put it on the forward wall inside storage compartment just behind the entrance door. Batteries are under the steps, probably 18 inches from the inverter. Inverter control mounted on the cabinet wall that sink is in, on the left side of entry steps.
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Old 05-23-2020, 12:31 AM   #6
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On my 31W the batteries are under the steps and the inverter is under the residential fridge (behind a drawer) that's directly aft of the stairs.
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Old 05-23-2020, 12:35 AM   #7
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I had a 2018 Outlaw 29H and they had the Inverter placed in the drivers side rear storage compartment when the batteries were under the entry ages. Thor didnít use the proper garage wire for that distance and they connected the (-) cable to chassis ground, which is not the best practice. For my application, the Inverter worked ok and I had not major issues.... but Iím sure there was a substantial voltage drop.

My 2020 Magnitude has the Inverter about 18 - 24Ē from the battery and it is directly connected. The voltage drop is minimal given how it is wired.

Bottom line..... it all depends on how much loaf you plan to place on the Inverter.
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Old 05-23-2020, 01:31 AM   #8
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I have a 2017 Four Winds 31W. Class C. The batteries are under the stairs, the inverter is under the fridge.
I just finished my solar install. I was able to place the charge controller, bus bar, battery cut off, circuit breakers and fuses under the fridge behind the storage drawer. 4-180W panels up top and changed out the batteries to agm.
Now just need to get on the road
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Old 05-23-2020, 01:33 AM   #9
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Quote:
Originally Posted by Judge View Post
I had a 2018 Outlaw 29H and they had the Inverter placed in the drivers side rear storage compartment when the batteries were under the entry ages. Thor didnít use the proper garage wire for that distance and they connected the (-) cable to chassis ground, which is not the best practice. For my application, the Inverter worked ok and I had not major issues.... but Iím sure there was a substantial voltage drop.

My 2020 Magnitude has the Inverter about 18 - 24Ē from the battery and it is directly connected. The voltage drop is minimal given how it is wired.

Bottom line..... it all depends on how much loaf you plan to place on the Inverter.
They sure did some funny things with the design of those Outlaws...
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Old 05-23-2020, 01:58 AM   #10
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Post #3 is your answer. Nothing else to look up or read unless you want to bone up on basic electrical theory and I squared R losses.
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Old 05-23-2020, 02:03 AM   #11
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I have the 31L, and not too long ago I put in a renogy Wanderer solar controller and 100W panel. I want to do the inverter to, but just haven't yet.
Still on the fence about how best to do it.
My highest priority is the outlet under the TV in the living room to power my coffee maker.
In my thinking the most logical place to put it is in the cabinet with the water tank. I assume that's where you're thinking...close to battery, but a trick to get the power back to the breaker box/converter. I could just add an outlet up in the counter above and be done. Might work well enough for me....but it would be better to power some other outlets too.
so, the easiest I think is back under the bed and just accept the voltage drop.
That's what I did for the solar....landed the solar output onto the battery side of the house disconnect relay. Not perfect but it works well.

how/where are you planning to put your solar?
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Old 05-23-2020, 09:38 AM   #12
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Quote:
Originally Posted by 16ACE27 View Post
Post #3 is your answer. Nothing else to look up or read unless you want to bone up on basic electrical theory and I squared R losses.
It's informative.
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Old 05-23-2020, 09:48 AM   #13
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Originally Posted by blw2 View Post
I have the 31L, and not too long ago I put in a renogy Wanderer solar controller and 100W panel. I want to do the inverter to, but just haven't yet.
Still on the fence about how best to do it.
My highest priority is the outlet under the TV in the living room to power my coffee maker.
In my thinking the most logical place to put it is in the cabinet with the water tank. I assume that's where you're thinking...close to battery, but a trick to get the power back to the breaker box/converter. I could just add an outlet up in the counter above and be done. Might work well enough for me....but it would be better to power some other outlets too.
so, the easiest I think is back under the bed and just accept the voltage drop.
That's what I did for the solar....landed the solar output onto the battery side of the house disconnect relay. Not perfect but it works well.

how/where are you planning to put your solar?
I'm still working things out. I have the roof laid out but not to scale. Measures are correct. Visually, it's off. The antenna cable drops through the roof and I'd like to follow that. It drops me down into an overhead very near the void.

I need to measure the component compartment and make sure everything fits. If I had a CAD program, this would be easier.
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Old 05-23-2020, 11:58 AM   #14
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Originally Posted by The_Breeze View Post
I'm still working things out. I have the roof laid out but not to scale. Measures are correct. Visually, it's off. The antenna cable drops through the roof and I'd like to follow that. It drops me down into an overhead very near the void.

I need to measure the component compartment and make sure everything fits. If I had a CAD program, this would be easier.

Am I reading your drawing correctly..... are you installing 12 panels? What size panels? What the heck are you powering and how many batteries are you charging? I assume you are planning for some serious boondocking if I am reading your drawing properly.

With two Renogy 160W flexible panels and a 30A MPPT Controller on a sunny day I was able to power the 5000 BTU A/C unit in the garage of my old Outlaw 29H with the two stock 12V house batteries.

I've got those same two panels on my Magnitude now with four 6V batteries.
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Old 05-23-2020, 12:13 PM   #15
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wow, that's a lot of panels, gonna be a nice set up. Puts my single panel 100W set-up to shame.

Those panels are bit different size than mine...how many watts total are you planning?

I have loosely planned the option so that I could add one or two more panels but I doubt that I will on this MH based on current needs.

Your antenna is in a different spot than mine. I think yours is where it's supposed to be. By design there's a metal plate in the roof for mounting it there...but mine is further back for some reason, over the stove.

Anyway, I ultimately didn't go through the roof there because while I could get it into the upper cabinets there, I couldn't think of a way to get the cable to the lower cabinets and the battery....well also because I was trying to avoid additional penetrations in the roof, but mostly routing.
Well you could take it rearward to the fridge box and down, then back forward, but that's adding a lot of cable.
I thought about dropping it just exposed in the corner over behind the driver's seat where it wouldn't be seen by the slide, then through the floor and under the coach.

Ultimately I dropped mine into the black tank vent stack into the void behind the drawers under the closet in the bedroom, then through the cable chase Thor put in the floor going to the under bed area. Turned out to be a great way to get to that electrical area.
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Old 05-23-2020, 09:58 PM   #16
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Inverter Install

I installed a 1500W Inverter [max 150A] in my 24 ft class C. The only two adequate locations for the inverter were either under the passenger front seat, or under the refrigerator above the wheel-well of the coach. The inverter location MUST be dry. My batteries are under the steps.
I elected above the wheel-well. This required 8ft of 1/0 Gage [+/-] wire back to the batteries. I ran them behind the cabinets. A waterproof 250A circuit breaker was used. Choose an Inverter that has remote on/off capability.
As to the cable used, if you need more than 4ft length of each line, I recommend welding cable. It is fine strand and very efficient. I bought mine on Ebay.
Since then, I have installed four AC circuits from the Inverter: TV above the cab, Beside the stove for the coffee pot, By the dinette, and at the base of the elevated bed.
I am pleased with the outcome.
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Old 05-23-2020, 10:37 PM   #17
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THOR #12189
Quote:
Originally Posted by Judge View Post
Am I reading your drawing correctly..... are you installing 12 panels? What size panels? What the heck are you powering and how many batteries are you charging? I assume you are planning for some serious boondocking if I am reading your drawing properly.

With two Renogy 160W flexible panels and a 30A MPPT Controller on a sunny day I was able to power the 5000 BTU A/C unit in the garage of my old Outlaw 29H with the two stock 12V house batteries.

I've got those same two panels on my Magnitude now with four 6V batteries.
I said this was a WIP. I'm pushing limits and may fall back. I simply wanted to test the boundaries. They would be 100w panels wired in series then parallel. I'd wire groups of two in series and use a combining box to group six pairs in parallel. Straight up - I'm thinking it through.
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Old 05-23-2020, 10:41 PM   #18
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Quote:
Originally Posted by The_Breeze View Post
I said this was a WIP. I'm pushing limits and may fall back. I simply wanted to test the boundaries. They would be 100w panels wired in series then parallel. I'd wire groups of two in series and use a combining box to group six pairs in parallel. Straight up - I'm thinking it through.

That is an impressive configuration!

It would certainly help with keeping the batteries charged on less than perfect days.

Keep us posted once you decide on the final design and implementation.
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Old 05-23-2020, 10:42 PM   #19
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Quote:
Originally Posted by blw2 View Post
wow, that's a lot of panels, gonna be a nice set up. Puts my single panel 100W set-up to shame.

Those panels are bit different size than mine...how many watts total are you planning?

I have loosely planned the option so that I could add one or two more panels but I doubt that I will on this MH based on current needs.

Your antenna is in a different spot than mine. I think yours is where it's supposed to be. By design there's a metal plate in the roof for mounting it there...but mine is further back for some reason, over the stove.

Anyway, I ultimately didn't go through the roof there because while I could get it into the upper cabinets there, I couldn't think of a way to get the cable to the lower cabinets and the battery....well also because I was trying to avoid additional penetrations in the roof, but mostly routing.
Well you could take it rearward to the fridge box and down, then back forward, but that's adding a lot of cable.
I thought about dropping it just exposed in the corner over behind the driver's seat where it wouldn't be seen by the slide, then through the floor and under the coach.

Ultimately I dropped mine into the black tank vent stack into the void behind the drawers under the closet in the bedroom, then through the cable chase Thor put in the floor going to the under bed area. Turned out to be a great way to get to that electrical area.
There's a storage compartment above the steps that's right underneath the entryway. Looking at exit, thinking down through the roof, to the left, down the behind the passenger seat to the battery box. Clean, simple and one or three holes to mount the monitors and charge controller.
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Old 05-23-2020, 10:48 PM   #20
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Originally Posted by Judge View Post
That is an impressive configuration!

It would certainly help with keeping the batteries charged on less than perfect days.

Keep us posted once you decide on the final design and implementation.
I have a few more steps to go through and a lot more homework left. The synapsis are firing and it's all good.
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