Solar Panels

[mtdawg]

I'm sure this subject has been covered before, so let me apologize in advance for the redundancy. I've had my 2016 North Point at the dealer for the past week having some warranty issues dealt with (sticky Schwintek slide, door adjustment, etc.) One of the issues is with the battery life. I have the residential refrigerator and a 1000 watt converter running it when I'm unplugged. Recently I left it unplugged after a full charge, running only the refrigerator. Then next day, the batteries were down 2/3. I have four 12 volt deep cycle batteries. The service person called today to tell me the trailer was ready to be picked up. I asked about the batteries and he said they all tested good and the converter is charging correctly. He said that I should consider an alternative power source such as solar. His advice was 3 160 watt panels.

Here are my questions:

1: Should I convert from 12 volt to 6 volt batteries? This guy didn't think it would make enough of a difference to make it worthwhile until the batteries need to be replaced.

2: If I decide to add solar, do his numbers make sense? Would 3 panels of that wattage do the trick?

3: I'm fairly handy with a good working knowledge in electronics, so is this a project I'd be able to do myself?

4: Finally (whew!), do any of you have recommendations regarding brand? The trailer is pre-wired with connectors on the side and the roof.

Thanks for your patience and expertise.

Jim

[DanNJanice]

Originally Posted by mtdawg

I'm sure this subject has been covered before, so let me apologize in advance for the redundancy. I've had my 2016 North Point at the dealer for the past week having some warranty issues dealt with (sticky Schwintek slide, door adjustment, etc.) One of the issues is with the battery life. I have the residential refrigerator and a 1000 watt converter running it when I'm unplugged. Recently I left it unplugged after a full charge, running only the refrigerator. Then next day, the batteries were down 2/3. I have four 12 volt deep cycle batteries. The service person called today to tell me the trailer was ready to be picked up. I asked about the batteries and he said they all tested good and the converter is charging correctly. He said that I should consider an alternative power source such as solar. His advice was 3 160 watt panels.

Here are my questions:

1: Should I convert from 12 volt to 6 volt batteries? This guy didn't think it would make enough of a difference to make it worthwhile until the batteries need to be replaced.

2: If I decide to add solar, do his numbers make sense? Would 3 panels of that wattage do the trick?

3: I'm fairly handy with a good working knowledge in electronics, so is this a project I'd be able to do myself?

4: Finally (whew!), do any of you have recommendations regarding brand? The trailer is pre-wired with connectors on the side and the roof.

Thanks for your patience and expertise.

Jim

The first thing you need to do is an energy audit to find out what you are really using. You can do this one of two ways.
1) Get a battery monitor system, such as the trimetric and connect it to your batteries and monitor you system over a few days of camping. If you plan to do a lot of dry camping, this is a worthwhile investment.
2) Get a clamp on DC ampmeter. These are available from a variety of places, Sears, Amazon, etc. The main thing is the clamp on Hall Effect type of DC clamp. That way you can measure large current draws without opening you wiring up. If you have no meter currently, I would go this route.
Once you know roughly what the current draw of your various systems is, you can begin to form a good plan for your solar system.
Regarding the three 160W panels and 6V batteries. I think your mechanic's recommendations are pretty good. A good rule of thumb is 100W of panel per battery. This is what I have, although I just have fairly small current draw.

[klassic]

I'm in the process of getting solar ready now in my Nothpoint . I ordered a Morningstar MPPT30 and I'm putting a single 260watt panel on the roof.

I did some testing last weekend camping. After my 2 6v Trojans were fully charged I shut the shore power off and ran off the batteries and kept an eye on my voltage moniter.
Just the fridge running (I don't think the fan inside ever shuts off) and the parasitic draws from the CO detector, radio, and tv's the rig pulled 9-11 amps for the 5 hours I tested. (It got too hot and I had to turn on the AC, so back on with the shore power)

With my batteries having 220 ah and working with the 50% rule, I would only last about 10-12 hours and I didn't have any lights on.

The day before I traveled for about an hour and the fridge compressor was on for a good portion of that, then using the auto level the batteries were almost kaput. The levelers were having a hard time with little battery power ( I ran auto level 2 times)

That made my decision to put in solar. Two 6volts aren't enough. I love the residential fridge, it's a keeper. I'm needing solar to keep it going. 260watts isn't all that much, but I don't want to put a huge investment into this for the occasional 2 days I don't have power or a day stop over somewhere for a day.

If I need more ah's I'll get 2 more 6v's someday.

Tough call what to do about your 12v's...it's a shame to yank them and invest in 6v's. Plus it's tough getting 6v batteries in the bottom and top shelf of the battery compartment
Also I think 3 160watt panels might be too much for the pre wired 6ga Jayco put in. It also has a 30amp breaker pre installed too.

If you have deep pockets go nuts! My pockets got shallower after paying for my rig. Plus I have alligator arms to begin with.

Any solar gurus feel free to correct me on anything, or give some good advice.

[Mustang65]

Klassic is giving you a wealth of information regarding how you design your system. Based on his 5 hour test, his system was drawing 9 - 11 amps for the basic load on his 5er. So if you use 10 Amps from 6PM through 10AM you have 14 hours of a 10 Amp load, and that does not include watching TV, playing the radio or lights. That alone adds up to 140 Amp hours. Not sure of the total Ah of your 3 12 volt batteries, but I would guess that they add up to around 160 Ah's total, of which you can only use 80 Ah's, going by the 50% rule. So just for the basics you are already at 280 Ah's. My thoughts are that you will need to convert to 4 6 volt batteries like the Trojan T- 105's or T-145's, which would get you to 420 - 520Ah. This should give you enough reserve power to run your fridge, lights and some fans, allowing for some extra. That's the usage part of the equation, now for the supply part.

So, you know that you need to have a min of 140 Ah's used by your basic loads ( over night). Don't forget the other 10 hours of daylight load you need to add in to the equation (10Amp's*10hrs=100Ah load). So now you have 240 Ah's for a 24 hour day. You mentioned using 3 - 160 watt panels. If my calculations are correct that should be about 13Amps per panel (160/12=13..) * 3=40Amps * 5 (hours of good sunlight/NO shade/no cloudy or rainy days)= 200Ah's. So far, we are a little short on Ah's needed on a BRIGHT sunny day to charge your batteries.

Based on Klassic's test, I would not install less than 800 watts of SOLAR panels. The 800 watts should give you a little buffer for those not so sunny days, and give you enough energy to charge your batteries and run your other electrical devices during the day. I am assuming you want to be able to dry-camp also...

Klassic, if you don't mind check my math and logic as it is around 1AM and I am on the dreaded tablet... x!#@..

Oh you Will have to run new cables to the roof to support the additional solar panels

Click on COMMUNITIES above and go to the RVing with SOLAR social group for solar/battery/installation information

Don

[Mustang65]

Klassic, was it a constant 5 hour load of 9-10 amps, meaning the refrigerator's compressor was constantly running for that length of time? Or were there short bursts of 9-10 amps only when the compressor kicked on? This would change the total Ah needed? I can't see a fridge compressor lasting very long if it is constantly running.

The addition of SOLAR will eliminate the battery discharging while traveling.

Don

[klassic]

I don't know how that fridge works, there is hum of a fan that never shut off...it wasn't the compressor.
The inverter panel said it was drawing 7a and I forgot to mention I have hooked that up to the TV also, so mtdawg can take an amp or so out of the equation for TV parasitic draw

So if the fridge was actually drawin 6a dc, what is that after the inverter in AC? Divide by 10? So the fridge fan is using almost .75a AC?
Definitely no compressor running.
As soon as you open the door the lights go on and it jumps to 18 amps DC.

Every time I looked my voltage moniter was 8.5-11a the batteries were down to 12.25v after 5 hours
When I turned on different banks of lights (all LED) each bank would be around 1.75amps DC

I pulled the fuse for the radio and CO saved around .75a DC

Don't even think about running the roof vents
And keeping the water pump at minimal use. Plus using the levelers while boondocking. There isn't much left after 12 hours to get the rig back on the truck.

Forgot to mention the illuminated switches for the water pump and water heater take little DC Amps too.

I know my 260 watt panel isn't going to be much, but it will cover the 9-11 amps during the day.. Give maybe 10a to the batteries (I'm hoping for sun)
I should make 2 days without power. Right now I have a seperate 12 battery an a seperate bank for back up.

But still I'm about 1k$ CAD into this. Solar isn't cheap.

[Mustang65]

You do turn off the 5er's battery charge controller while not connected to shore power correct? I am not sure as to how they wire the controller in the 5er, which could add to the discharge total.

Don

[klassic]

Originally Posted by Mustang65

You do turn off the 5er's battery charge controller while not connected to shore power correct? I am not sure as to how they wire the controller in the 5er, which could add to the discharge total.

Don

I haven't got to the install yet.
My wife happened to be in Cali for the last 3 days so I amazoned a 1 day delivery of a Morningstar MPPT 30 to her hotel yesterday.
They are not cheap up here in the north.

The panel I found is pretty much $1 a watt 45 mins from me in Toronto.
Tell me what you think of this Don.
The Jkm260.
http://www.jinkosolar.com/ftp/EN-JKM270P-60(4BB).pdf

Sorry about hijacking your thread mtdawg

[Mustang65]

Originally Posted by klassic

.

The panel I found is pretty much $1 a watt 45 mins from me in Toronto.
Tell me what you think of this Don.
The Jkm260.
http://www.jinkosolar.com/ftp/EN-JKM270P-60(4BB).pdf

Sorry about hijacking your thread mtdawg

Looks like a pretty good deal to me.. I am just learning how much of a price difference there is between Canada and the US, never gave it much thought before.

Good Luck,

Don

[klassic]

Go on Amazon.ca and check out the price of Morningstar controllers.

[klassic]

Originally Posted by klassic

I'm in the process of getting solar ready now in my Nothpoint . I ordered a Morningstar MPPT30 and I'm putting a single 260watt panel on the roof.

I did some testing last weekend camping. After my 2 6v Trojans were fully charged I shut the shore power off and ran off the batteries and kept an eye on my voltage moniter.
Just the fridge running (I don't think the fan inside ever shuts off) and the parasitic draws from the CO detector, radio, and tv's the rig pulled 9-11 amps for the 5 hours I tested. (It got too hot and I had to turn on the AC, so back on with the shore power)

With my batteries having 220 ah and working with the 50% rule, I would only last about 10-12 hours and I didn't have any lights on.



The day before I traveled for about an hour and the fridge compressor was on for a good portion of that, then using the auto level the batteries were almost kaput. The levelers were having a hard time with little battery power ( I ran auto level 2 times)

That made my decision to put in solar. Two 6volts aren't enough. I love the residential fridge, it's a keeper. I'm needing solar to keep it going. 260watts isn't all that much, but I don't want to put a huge investment into this for the occasional 2 days I don't have power or a day stop over somewhere for a day.

If I need more ah's I'll get 2 more 6v's someday.

Tough call what to do about your 12v's...it's a shame to yank them and invest in 6v's. Plus it's tough getting 6v batteries in the bottom and top shelf of the battery compartment
Also I think 3 160watt panels might be too much for the pre wired 6ga Jayco put in. It also has a 30amp breaker pre installed too.

If you have deep pockets go nuts! My pockets got shallower after paying for my rig. Plus I have alligator arms to begin with.

Any solar gurus feel free to correct me on anything, or give some good advice.

EDIT... I meant Jayco's prewire is 8 gauge.

[mtdawg]

Originally Posted by klassic

EDIT... I meant Jayco's prewire is 8 gauge.

Thanks Klassic, you've got a lot of helpful info. In the end we bit the bullet and are having the dealer install the solar panels. They claim the 160 watt panels will serve our needs and at this point I'm going to assume that they are familiar with the wiring needs. It's going to cost us more, but with the trailer still being under warranty, I wanted them to do the work so they will have less of an opportunity to weasel out of any warranty repairs which might occur in the future. Regarding the expense, well I guess my kids can inherit it when I croak.

The dealer did recommend going 6v when the time comes to replace the batteries. I'm noticing a big variation in price. I assume this has to due with amp hours. More research needed I suppose.

Jim