Dual Solar Panels on a 21

[stephen99]

Wow, lots of good info here. A couple more questions. Does ETI install the Samlex SCC-30AB charge controller? Where is it located in a 21? If you add an additional solar panel where does it connect on the controller? Same terminals as the roof mounted panel?

[OldstersOutside]

Alan

Great insights. I'm leaning towards having ETI install the two panels and at least doing some prep work for adding the additional portable in the future. It's good to hear about the AGM batteries as well. I've been doing my research on them as well and see some advantages of going with them. Thank you.

Oldsters

[Brian B-P]

Originally Posted by stephen99

Does ETI install the Samlex SCC-30AB charge controller?

If you do a Google Search of EscapeForum.org for "SCC-30AB" you'll find a few threads in which people have specifically mentioned this controller by model... although there's a lot more information in discussions than that, because the model is always mentioned.

[stephen99]

I emailed Sarah to get the final word on which charge controller they will install and she said they are currently installing the Carmanah GP-PWM-30 but she cautioned it could change by the time my 21 is built in 6 months.

[padlin]

Which is the GoPower.

[Brian B-P]

Originally Posted by stephen99

... they are currently installing the Carmanah GP-PWM-30 ...

Originally Posted by padlin

Which is the GoPower.

Product page link: Go Power 30 Amp Digital Solar Controller (Model: GP-PWM-30)
Go Power! is a division of Carmanah.

[7th Heaven]

Originally Posted by rbryan4

The hard part is getting wax under the panel. I rigged up a pad attached to a long plastic rod so I can clean and wax under there. As long as the finish has a good coat of protection on it, I think you're good to go.

**Confused**
I was under the impression that flexible panels are adhered directly to the roof. if so I wouldn't think there would be a gap under the panel?

[SFDavis50]

The Escape provided panels mount above the roof and it is difficult to get wax under them. The flexible panels are bonded to the fiberglass shell of the trailer. Your question seems like a valid one; if the panel generates a lot of heat does that have a long term impact to the fiberglass shell, underlying insulation etc. On a hot sunny day will the bonded panels radiate much heat into the interior of the trailer?

[float5]

This is our panel. Don't know what they are doing now.

[Losangeles]

Originally Posted by float5

This is our panel. Don't know what they are doing now.

I am 99.99999% sure they are still doing just exactly that.

[rbryan4]

Originally Posted by 7th Heaven

**Confused**
I was under the impression that flexible panels are adhered directly to the roof. if so I wouldn't think there would be a gap under the panel?

My reply dealt with the stock panels, not flexible ones. If the original question was referring to the flexible panels, I didn't see it.

[padlin]

Originally Posted by SFDavis50

The Escape provided panels mount above the roof and it is difficult to get wax under them. The flexible panels are bonded to the fiberglass shell of the trailer. Your question seems like a valid one; if the panel generates a lot of heat does that have a long term impact to the fiberglass shell, underlying insulation etc. On a hot sunny day will the bonded panels radiate much heat into the interior of the trailer?

Found this list of pros and cons on the flexible panels in the Wynn's RV blog. Flexible RV Solar Issues Revealed - Our One Year Review

[Ron in BC]

Originally Posted by SFDavis50

On a hot sunny day will the bonded panels radiate much heat into the interior of the trailer?

Sun is shinning on my panel. Top surface temperature is 46 C; underside is 51 C. I was a little surprised by that but I took multiple readings. So fair to say that the panels slightly increase the surface temperature of the fiberglass.

On the other hand I'm not sure there is any harmful effect to the f.g. I've done things like pour molten lead onto fiberglass without any apparent harm.

Ron

[Patandlinda]

Originally Posted by Ron in BC

Sun is shinning on my panel. Top surface temperature is 46 C; underside is 51 C. I was a little surprised by that but I took multiple readings. So fair to say that the panels slightly increase the surface temperature of the fiberglass.

On the other hand I'm not sure there is any harmful effect to the f.g. I've done things like pour molten lead onto fiberglass without any apparent harm.

Ron

Ron you caught my attention . What do you think of the flexible panel or maybe 2 on our roof ? Pat

[freespirit]

Originally Posted by float5

This is our panel. Don't know what they are doing now.

and the ETI mounting methods vary...

[float5]

Originally Posted by freespirit

and the ETI mounting methods vary...

They tried to not bolt them but when some panels came off, they went to bolting. That was shortly before we picked up.

[Ron in BC]

Originally Posted by Patandlinda

Ron you caught my attention . What do you think of the flexible panel or maybe 2 on our roof ? Pat

This year a friend replaced his boat typical hard frame solar panels with the lightweight ones. He's one really bright guy in electronics and he's really happy with them. He uses them in a semi portable way and finds the light weight an advantage. He had a mishap and a heavy object fell on one panel. It marked it but didn't damage the output capacity. I'm thinking that if I add a second panel I'll go with the flexible panel as I'd want it to be portable, or be able to go up and down on a pole.

Ron

[Patandlinda]

Originally Posted by Ron in BC

This year a friend replaced his boat typical hard frame solar panels with the lightweight ones. He's one really bright guy in electronics and he's really happy with them. He uses them in a semi portable way and finds the light weight an advantage. He had a mishap and a heavy object fell on one panel. It marked it but didn't damage the output capacity. I'm thinking that if I add a second panel I'll go with the flexible panel as I'd want it to be portable, or be able to go up and down on a pole.

Ron

Ron can you explain a little more about having the panel portable ? I found some a lot cheaper then the go power , I was thinking of .do you mean instead of gluing down on your roof just placing say on the roof when your parked ? I know about your panel on the pole . How would you accomplish with the flexible panel . It only weighs 5 lbs what I was looking at . Do you think it would be a mistake to glue down on roof ? I am picking your brain as you can see . Pat

[SFDavis50]

Originally Posted by Ron in BC

Sun is shinning on my panel. Top surface temperature is 46 C; underside is 51 C. I was a little surprised by that but I took multiple readings. So fair to say that the panels slightly increase the surface temperature of the fiberglass.

On the other hand I'm not sure there is any harmful effect to the f.g. I've done things like pour molten lead onto fiberglass without any apparent harm.

Ron

I assume your panels have an inch or more of space between them and the roof so air can circulate and they shade the roof.
51 C (123.8 F) is pretty hot; in Arizona or Texas it would be a lot hotter. If mounted directly to the roof surface they would radiate a lot of heat into the trailer which may be good in winter but bad in the summer.
I don't know if the flexible types generate more or less heat but perhaps you could make window awnings for use in the summer then strap them to the roof in the winter.

[Ron in BC]

Originally Posted by Patandlinda

Ron can you explain a little more about having the panel portable ?

I'm not sure what brand my friend's panels are but they're the kind that are semi rigid plastic, not the really flexible rubber kind. He made a very lightweight frame for them out of aluminum angle so that he could attach brackets to them etc. He's up the coast right now without very good cell coverage but I was going to get the website info for them when he returns.

Ron