Forum Discussion

KE6IRJ's avatar
KE6IRJ
Explorer
Apr 03, 2016

Solar Questions, yes more solar questions

Okay, before you say it, I did search, and have been reading on this for days.

Here is my question.

I have a bonus coming possibly and am trying to decide if I want to use it for solar on our trailer. I intend to use the trailer mainly off the grid, and have fall hunting trip coming up for 7 days.
Currently, I have 2 GC2 batteries, plan to go to LED lights, and a propane heater other than the trailer heat.

So, in reading, I know I want an MPPT controller, remote monitor head, and probably 200-250 watts to keep my batteries charged for the week trip.

Is it better to shop around and piece together a system or stay with something put together by someone who knows?

I was thinking this one, because they are local to me and I have seen them in action on our last trip.
http://www.solar-electric.com/solar-panels-mounts-kits-accessories/prsy/rvandsmbasoc/rv-solar-kit-280-watts-mppt.html

I don't think I need an inverter right away, since I don't use other devices when camping right now. Do I need replace my built in power converter or is this all additional?

So, am I on the right track? Are there companies or brands to avoid? Better prices I have not found? Fill me in, what am I missing?
  • pianotuna's avatar
    pianotuna
    Nomad III
    May 08, 2016
    Hi,

    The upside is you will have time to digest exactly what you need/want for solar, and that the price may well be lower.

    Kudos on the led lighting and the tires.

    KE6IRJ wrote:
    Well, my expected bonus was not what was expected, so the LED upgrade and a few smaller needs as well as tires came first, so solar will have to wait.
    :-(
  • KE6IRJ's avatar
    KE6IRJ
    Explorer
    May 08, 2016
    Well, my expected bonus was not what was expected, so the LED upgrade and a few smaller needs as well as tires came first, so solar will have to wait.
    :-(
  • Almot's avatar
    Almot
    Explorer III
    Apr 17, 2016
    KE6IRJ wrote:

    Where do the breakers go in line?

    Everywhere.
    panels -> (Junction box?) ->#1 disconnect switch -> controller -> #2 breaker -> Pos bus -> battery fuse -> battery.

    #1 can be switch or breaker in Baby Box, or skip the switch and use MC4 to disconnect on the roof.
    #2 and Pos bus - in the Baby Box.

    It is convenient to also add #3 - loads breaker, it also goes into Baby Box.

    You can skip the Baby and have #2 and #3 as fuses - not breakers - less convenient.

    Battery fuse will be on or near the battery.
    KE6IRJ wrote:

    I have settled on the Morningstar TS-45 for my controller. Most options I want for the price and highly rated.

    ...
    What am I missing, beside marine grade wire, 4-gauge cable?

    A lot of things are highly rated, doesn't mean you need them. I wouldn't trust Amazon ratings too much, average tech level is pretty low. 2*165W should be alright with 25A controller.

    Not sure about marine grade cable - you are not installing this on the boat, are you? :)

    4-gauge will be enough between 2*165W panels and controller, and overkill from controller to battery. Use Voltage drop calculator, max 2% drop.
  • westend's avatar
    westend
    Explorer
    Apr 17, 2016
    It's convenient to have a circuit breaker in series with the power wire from the modules. It allows to disconnect any solar power when working on the batteries or the rest of the 12V system. Some controllers always need the battery connections connected before the solar panel power wires if the module is producing power. If you don't interrupt the module power and disconnect the battery connection, good bye controller.

    I use this one: CB manual breaker
  • KE6IRJ's avatar
    KE6IRJ
    Explorer
    Apr 16, 2016
    scrubjaysnest wrote:
    You won't get a better price on the Midnight Solar Big Baby Box and breakers then at NAWS, solar-electric.com. Two 150 watt, 12 volt panels run about $330 to $350 on ebay with free shipping.


    Okay, stupid question but why do I need circuit breaker box?

    I thought the solar panel connectors brought all the amps down on 2 wires, then to the controller, then to the battery. Where do the breakers go in line?

    Panel 1 ---> Panel 2 ===> Converter ---> Battery


    Due to size limitations on my roof, I am looking at 2 of the 165 Watt panels from Everbright

    or 2 of the 100 Watt panels from Renology to start and I would have room for 1 more if desired later

    I have settled on the Morningstar TS-45 for my controller. Most options I want for the price and highly rated.

    ***All can be found on Amazon, but I have the worst luck with links even using the dummy buttons. You know what they say, we will find a bigger dummy, and I am it.



    So... talk to me. What am I missing, beside marine grade wire, 4-gauge cable?
  • Almot's avatar
    Almot
    Explorer III
    Apr 05, 2016
    pianotuna wrote:
    Yes, it is a quality controller. It is intended for two battery banks, so it might be cheaper to have the plain jane sunsaver. Having the battery temperature sensor is a "must do".

    I'm not sure it has adjustable voltage set points.

    Ss Duo is 25A, single-bank SS is 20A max if I'm not mistaken. Setpoints on Duo can be custom-set, though this requires a laptop AND optional meter-bus adapter. Remote temp sensor is also optional - yes, very desirable to have. Remote display is extra. And all you'll get is 25A, i.e. 2*160W or 2*180W max.

    With 2 panels I would think about Bogart Trimetric combo SC 2030 - TM 2030. 30A, ~$300 with everything adjustable including automatic Absorption adjustment and complete battery monitor.

    Or - Xantrex/Trace 35A and 3*160W panels. Heck, my 490W fills AGM bank to ~93-95% before noon when it exits Absorption, and then it floats until sunset. As long as it doesn't rain. Don't need no battery monitor, muchas gracias.
  • red31's avatar
    red31
    Explorer
    Apr 05, 2016
    KE6IRJ wrote:


    In order to give an accurate use on the remote display, the trailer power has to go through the perry's on the right, marked by a light bulb, right?


    take a look at the brochure, page 2
    load amp-hours is not available for that controller
    http://support.morningstarcorp.com/wp-content/uploads/2014/07/RemoteMeterENG1.pdf

    my non MS controller displays discharge KWH only if the load terminals are used. Typical tt user does not use the load terminals since loads can be more than the controller's rating.
  • pianotuna's avatar
    pianotuna
    Nomad III
    Apr 05, 2016
    No the light bulb indicates the ability to turn on and off a load. I.E. on at dusk off at dawn.

    Yes, it is a quality controller. It is intended for two battery banks, so it might be cheaper to have the plain jane sunsaver. Having the battery temperature sensor is a "must do".

    I'm not sure it has adjustable voltage set points.
  • KE6IRJ's avatar
    KE6IRJ
    Explorer
    Apr 05, 2016
    Okay, typing and linking on my phone is difficult but let me try to clarify.

    This controller is what I am referring to for reference.
    Link

    The solar panel wires go into the controller in the marked slots on the left.

    The power to the batteries go out through the marked ports in the middle.

    In order to give an accurate use on the remote display, the trailer power has to go through the perry's on the right, marked by a light bulb, right?

    Is this a decent converter?

    Edit, that one does not have the light bulb indicator, but I have seen it on others.
  • JiminDenver's avatar
    JiminDenver
    Explorer II
    Apr 05, 2016
    Renogy may offer some controllers but they are just rebadged controllers that can be had on ebay for less without their label. In some cases the regranded version is last years while a mewer model is available. It happens with windynation and Eco-w too, Eco-w may make some controllers themselves but they rebrand others.

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