23 replies to this topic

[Vic Harder]

I would be guessing, but ... I suspect the wires from your rear facing portable connector are wired directly to the battery.  If so, then you can just plug in the portable and use their controller.

 

I that guess is wrong - and the portable connector goes to the on board controller, then you will need to bypass the controller on your Renogy portable unit.

[muttmaster]

I will check the back of the ZAmp controller to see if the rear SAE plug connect there. If it goes to the battery directly, they will be best for me as I would have to bypass the Portable’s controller. What damage can if really cause if juice from one portable panel goes thru two different controllers ? Best not to? I guess, has anyone done that or seen the effects? I can’t be the only solar novice that have that question.

[muttmaster]

I checked the Zamp controller onboard and found wire from the rear plug is connected to bus that is connected to the back of the controller. The bus is also connected to roof top panel I assume and the batteries. I better ask FWC for advise on how to use my portable.

[Advmoto18]

"Simple" and "solar" shouldn't be used in the the same phrase!      They should be though...

 

Plenty of good 150-230W panels on the market with integrated controller.  Just be mindful of the stowed form factor and weight.  A 180W Zamp portable weighs 34# and closed dimensions are 39.5“ x 21.5" x 3". 

 

An external SAE plug wired to a high quality circuit break is a must to protect the circuit and eliminate a potential fire hazard.  Matching the circuit break amperage equal to the controller amperage is a safe rule of thumb.

 

Most reputable portable panels will be fused between the panel and embedded/installed controller.  

Edited by Advmoto18, 05 November 2018 - 12:27 PM.

[Vic Harder]

I dunno about this Advmoto18.  If there is a fuse, it's purpose is to protect the wire and prevent fires.  To do that, the fuse should be located at the power source, so at the panel, not at the controller end.

 

FYI, I don' t have any on my roof, nor do I have any at the far end of 100' of cable for my portables.  

[Advmoto18]

Vic...

 

Renogy recommends fusing between the panel and the controller and the controller and the battery bank.  The fuse between the controller and battery bank should be equal to the controller amperage.

 

Is a fuse between the panel(s) and controller required?  No, but, it doesn't hurt as it is only another layer of protection.

 

Rather then fuses, I used Blue Seas marine circuit breakers.  Panel to controller side CB is equal to max output of all panels.

 

I have a CB between my roof panel and controller;  just before the controller.  Another CB just inside the camper shell from the external SAE port from my portable panel.

 

I probably over-fuse and CB my electrical schemes most likely due to my aviation background.  I don't like fire!  Lost a pilot buddy on the Swiss Air flight that crashed off Nova Scotia 2 decades ago due to an electrical fire in the cockpit.

 

Fuses and CBs are cheap insurance IMO.

Edited by Advmoto18, 05 November 2018 - 07:14 PM.

[rubberlegs]

Hey y'all, I'm thinking of jumping into the solar bandwagon. Our battery goes down to near 60% or even 50% after a night of pleasant camping. What do you think about the recommendation on this website? Agree with their assessment? https://campaddict.c...e-solar-panels/

[Wandering Sagebrush]

Hey y'all, I'm thinking of jumping into the solar bandwagon. Our battery goes down to near 60% or even 50% after a night of pleasant camping. What do you think about the recommendation on this website? Agree with their assessment? https://campaddict.c...e-solar-panels/

I have an older Zamp 80 watt, and it does a good job. Renogy has a good reputation as well. No info on the other.

I think you would do well with Zamp or Renogy, possibly the third.

Why not go with an onboard system? You could keep the batteries topped off when ever the camper is outside.

[Vic Harder]

I agree with WanderingSagebrush.... go for a permanent install rather than portable, unless there is a good reason to go portable?  Like you have a canoe on the roof, park in the shade, or some other reason.

 

Before you can size the panels correctly, we need to know how many AH of battery you have.  Typically you would need to get at least the same or up to 2x as many watts as AH.  I have 250AH, and 465 watts of solar.

[rubberlegs]

We have the standard 89 Ah battery that came with our Fleet, and seem to use 30-50% in a night (based on measuring with a voltmeter occasionally). I think portable is better for us because of two reasons: we can park in the shade, and it's simpler to retrofit on the camper -- just plug it in. I figured I could put it on top if we are in the sun, and maybe it's less chance of being stolen while we are out hiking. But I've not figured out how to put it up there -- I tried standing on a tire and holding the edge of the roof today (roof down of course) and it's not a great handhold!

 

I had "electric car range anxiety" type feelings about our battery usage, so hope the solar mitigates that.

 

Then the other subject is how much. I saw on this website (https://www.speciali...ze-your-rv.html) that somewhere around 100W is about right, which kinda surprised me. But after calculating a few numbers it seems about right. I like the 90W Zamp portable if money is no object (https://www.zampsola...t-long-portable) due to size, weight, durability, plug and play with the new camper.

 

Then there's the fun factor about solar. Already have solar for our house which has worked well for several years, and almost paid for. Even looked up the solar insolation data for several areas we'd camp (e.g. https://solarenergyl...lorado-springs/) and I think there's enough if we park all day. If we don't park all day, the alternator works great but I've noticed it takes a couple hours to recover from overnight usage.

 

A calculation:

 

Say we use 45 Ah per day. That's (45 Ah) * (12V) = 540 Wh

Insolation is 3 kWh/m2-day in February.

90W panel is 27"x30". Thus:

 

(3 kWh/m2-day) * (27 in) * (30 in) / (1550 in2/m2) = 1500 Wh, almost 3x what we'd need. Ergo 90W is a good size, which is about the same as the battery Ah rating as you suggested.

Edited by rubberlegs, 16 November 2018 - 05:04 AM.