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Vintage465's avatar
Vintage465
Nomad
Oct 22, 2019

Up grading my Solar Conductors

I've been working on running new solar conductor from the roof to the pass thru near the batteries. Here is what I've done. From the existing Zamp Combiner box(to be replaced) it I fished the #4 conductors over to the drivers side wardrobe in the trailer. Down the inside of the wardrobe. Since it's pre-wired there was good access in the overhead cabinet above the bed as there is an inspection/access panel to the pre-wire.



Then I had to run it exposed in the short space where the night stand is. I took some poplar hobby wood from Home Depot and cut it to fit on my table saw and then "skinned" it with the "panel matching" tape that ORV uses to trim inside corners and splices where the light paneling meet. It came out OK. Not 100% proud. My mind visualized it one way....my 60 year old body being tied up in knots in that little space got it done another way! Lucky thing is my C-Pap Machine goes down there and it's really never visible. At the top of the trim on the left, what looks like discoloration is actually a reflection from that chrome 12v outlet plate. That's for my C-Pap..................Yes I know "TMI"
  • DrewE's avatar
    DrewE
    Explorer II
    Oct 22, 2019
    Looks good enough to me. Actually, there's a good chance that this is the most neatly installed and best secured wiring on the entire RV.
  • Vintage465's avatar
    Vintage465
    Nomad
    Oct 22, 2019
    DrewE wrote:
    Looks good enough to me. Actually, there's a good chance that this is the most neatly installed and best secured wiring on the entire RV.


    I get a little carried away sometimes. Going for that "Aircraft" quality look!
  • SidecarFlip's avatar
    SidecarFlip
    Explorer III
    Oct 22, 2019
    One thing that has always bothered me is the puny wiring that comes in every solar kit and I don't care who makes them. Heavier the wire, the lesser the voltage and amperage drop is over distance. I'm going to install a kit (probably Zamp) but I'll substitute neoprene insulated stranded welding cable for puny wires with tinned and soldered on copper lugs too.
  • Vintage465's avatar
    Vintage465
    Nomad
    Oct 22, 2019
    SidecarFlip wrote:
    One thing that has always bothered me is the puny wiring that comes in every solar kit and I don't care who makes them. Heavier the wire, the lesser the voltage and amperage drop is over distance. I'm going to install a kit (probably Zamp) but I'll substitute neoprene insulated stranded welding cable for puny wires with tinned and soldered on copper lugs too.


    ORV actually does better than most with 8ga wire. I tend to think the newer ones are 6ga. I installed 4ga and I'm moving the controller down near the batteries. I was losing right at a 1/2 volt on my charging voltage. Too much.
  • CA_Traveler's avatar
    CA_Traveler
    Explorer III
    Oct 22, 2019
    Vintage465 wrote:
    SidecarFlip wrote:
    One thing that has always bothered me is the puny wiring that comes in every solar kit and I don't care who makes them. Heavier the wire, the lesser the voltage and amperage drop is over distance. I'm going to install a kit (probably Zamp) but I'll substitute neoprene insulated stranded welding cable for puny wires with tinned and soldered on copper lugs too.


    ORV actually does better than most with 8ga wire. I tend to think the newer ones are 6ga. I installed 4ga and I'm moving the controller down near the batteries. I was losing right at a 1/2 volt on my charging voltage. Too much.
    One of the reasons I choose serial panel connection - 62' of 10ga wire for 3 panels with a 0.6% voltage drop.
  • Vintage465's avatar
    Vintage465
    Nomad
    Oct 23, 2019
    CA Traveler wrote:
    Vintage465 wrote:
    SidecarFlip wrote:
    One thing that has always bothered me is the puny wiring that comes in every solar kit and I don't care who makes them. Heavier the wire, the lesser the voltage and amperage drop is over distance. I'm going to install a kit (probably Zamp) but I'll substitute neoprene insulated stranded welding cable for puny wires with tinned and soldered on copper lugs too.


    ORV actually does better than most with 8ga wire. I tend to think the newer ones are 6ga. I installed 4ga and I'm moving the controller down near the batteries. I was losing right at a 1/2 volt on my charging voltage. Too much.
    One of the reasons I choose serial panel connection - 62' of 10ga wire for 3 panels with a 0.6% voltage drop.


    I'm thinking you meant to type "Series" and not "Serial". Either way, if I don't get what I'm looking for by doing this, I will upgrade to an MPTT type controller and go series to stiffen up the rig. Right now I figured I'd get all the wiring done the way I want it and move the existing controller down by the batteries and see how she performs. My existing controller comes up 4 volts short of being able to handle my panels in series. I still get a little brain wounded by trying to mentally sort out the volts vs amps, series vs parallel thing. Better volts with series, better amps with parallel. The more I study or get lectured, seems like it comes down to watts and getting them watts to the battery.
  • CA_Traveler's avatar
    CA_Traveler
    Explorer III
    Oct 23, 2019
    Yes series connected panels, thanks for the correction.

    Voc increased with lower panel temperature and exceeding the Voc can damage the controller, hence a colder weather consideration. The Morningstar String Calculator will check this. You have to use a MS controller but you get the panel results.
  • Vintage465's avatar
    Vintage465
    Nomad
    Oct 23, 2019
    CA Traveler wrote:
    Yes series connected panels, thanks for the correction.

    Voc increased with lower panel temperature and exceeding the Voc can damage the controller, hence a colder weather consideration. The Morningstar String Calculator will check this. You have to use a MS controller but you get the panel results.


    OK, so a little help here with the acronyms. Voc? MS controller?
  • CA_Traveler's avatar
    CA_Traveler
    Explorer III
    Oct 23, 2019
    Voc is voltage open circuit, a panel spec. Panel parameters are temperature sensitive and you can do the calculations yourself since the temperature coefficients are also part of the panel spec.

    Normally only Voc is critical as a controller may not survive exceeding it's max input voltage.

    At 0F my 60 cell panel Voc is 5 volts higher, hence 15V for 3 series panels.

    25C (77F) is the base and amps rise while voltage drops with increasing temps and the opposite for decreasing temps.

    MS is Morningstar
  • Vintage465's avatar
    Vintage465
    Nomad
    Oct 23, 2019
    CA Traveler wrote:
    Voc is voltage open circuit, a panel spec. Panel parameters are temperature sensitive and you can do the calculations yourself since the temperature coefficients are also part of the panel spec.

    Normally only Voc is critical as a controller may not survive exceeding it's max input voltage.

    At 0F my 60 cell panel Voc is 5 volts higher, hence 15V for 3 series panels.

    25C (77F) is the base and amps rise while voltage drops with increasing temps and the opposite for decreasing temps.

    MS is Morningstar


    Sweet! My VOC is 18.4 volts for a max of 55.2 volts if wired in Series. My Controller is good for 50v. So were not going that way until I get a new controller. Bottom line is, if I can get what I need by doing what I've done and using the existing controller in parallel but closer to the battery bank, it will stave off the immediate need for a new controller. Too many other project taking my cash right now!

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