Solar Wiring help

[Jonesdds]

Using a Victron 100/20 MPPT controller and have two 100 watt Renogy panels-not same models but similar.

The RNG-100D-SS is one that I plan to make moveable and other one will stay on the roof. The 100D-SS will be mounted on the roof as well as other when not using away from trailer to chase the sun.

Both panels have 14 gauge out of them, about 2 ft, and MC4 connectors. I plan to have some kind of connection outlet on the side of the trailer for the one I will use remotely some of the time. So form that one I'll have a shorter line when its on the roof and a 30-50 ft line to it when using it remotely. For the outlet it will connect to I'm thinking Zamp, SAE or Anderson power pole. Thoughts on which would be best?

Wire gauge. I have a 20 ft 10 gauge from the primary fixed rooftop panel(the 100D-SS). Wondering if it's overkill(since panel has 14 gauge) having 10 gauge but assume there's no negative to using it. My long line I'd use to the remote panel is 10 gauge as well.

For the panel that I'll sometimes move from roof to a remote location I'll keep in unhooked when traveling and hook up when camped. Whatever I use as an outlet(Zamp, SAE or Anderson) is what my extention will be for the remote use of the panel. One concern is it being water proof in case of rain. I could make it MC4, the extension cables but is it an issue plugging and unplugging these, it's been suggested it is a problem. I have the tool and they are easy to recrimp new ones but...

Also, inside the hatch where the controller is I'll want to connect the permanent roof panels 10 gauge wiring to the outlet that will connect the remote panel. The outlet will be only a foot or less from the controller. What would the best way be to connect them before connecting to the controller. It would be a parallel connection which is somewhat reducing my voltage abilities vs. series but I see no way to do this in series given use of the panel remotely. Should I connect up with two into one MC4 connectors? Since those 4 wires are bare, no connectors, is there a power block of some kind that could be used to take the two positives to one and same for negative?

Lastly, looking at the specs of the two panels, I assume it's not necessary to fuse these, correct, when in parallel?

[booster]

Originally Posted by Jonesdds

Using a Victron 100/20 MPPT controller and have two 100 watt Renogy panels-not same models but similar.

The RNG-100D-SS is one that I plan to make moveable and other one will stay on the roof. The 100D-SS will be mounted on the roof as well as other when not using away from trailer to chase the sun.

Both panels have 14 gauge out of them, about 2 ft, and MC4 connectors. I plan to have some kind of connection outlet on the side of the trailer for the one I will use remotely some of the time. So form that one I'll have a shorter line when its on the roof and a 30-50 ft line to it when using it remotely. For the outlet it will connect to I'm thinking Zamp, SAE or Anderson power pole. Thoughts on which would be best?

Wire gauge. I have a 20 ft 10 gauge from the primary fixed rooftop panel(the 100D-SS). Wondering if it's overkill(since panel has 14 gauge) having 10 gauge but assume there's no negative to using it. My long line I'd use to the remote panel is 10 gauge as well.

For the panel that I'll sometimes move from roof to a remote location I'll keep in unhooked when traveling and hook up when camped. Whatever I use as an outlet(Zamp, SAE or Anderson) is what my extention will be for the remote use of the panel. One concern is it being water proof in case of rain. I could make it MC4, the extension cables but is it an issue plugging and unplugging these, it's been suggested it is a problem. I have the tool and they are easy to recrimp new ones but...

Also, inside the hatch where the controller is I'll want to connect the permanent roof panels 10 gauge wiring to the outlet that will connect the remote panel. The outlet will be only a foot or less from the controller. What would the best way be to connect them before connecting to the controller. It would be a parallel connection which is somewhat reducing my voltage abilities vs. series but I see no way to do this in series given use of the panel remotely. Should I connect up with two into one MC4 connectors? Since those 4 wires are bare, no connectors, is there a power block of some kind that could be used to take the two positives to one and same for negative?

Lastly, looking at the specs of the two panels, I assume it's not necessary to fuse these, correct, when in parallel?

With two panels and one used only some of the time, you will need to be parallel wired, unless the controller auto switches input voltage for you. With a 50 ft difference in cable length, which for resistance is 100" of wire as both ways count, you would want to look at the resistance of your shorter wiring and then calculate from the charts just how big you would have to got to get the same resistance in the long wiring. If you don't, the long wiring will kill the output from that panel, I think.

[@Michael]

I did something similar with a pair of 110W panels. One on the roof, the other portable, wired in parallel.

• I used SAE connectors for all but the first connection from the panels, which are the panel-attached MC4's. I have a short MC4<->SAE adapter cable on the portable panel side of the connection. The roof panel connects to an MC-4 junction box that is glued over the top of a hole in the roof.
• I used 10ga. wire throughout, including the SAE pigtails and 25ft. extension for the portable panel.
• I'm connecting the portable panel inside the van. I droop the portable wire out the back door and close the door, letting the wire get pinched by the door gasket. I didn't want to mess with drilling a hole in the side of the van.
• To parallel the 10Ga. wires from the roof and portable panels, I either used double spade connectors (2 into one), or piggyback spade connectors, or terminal blocks.
• Where the portable panel connects in the van, I put an on/off switch and voltmeter, with the voltmeter on the panel side of the switch. I did this so that I know for sure the external panel polarity is correct before it's connected to the Victron.

It works.

[Jonesdds]

Originally Posted by @Michael

I did something similar with a pair of 110W panels. One on the roof, the other portable, wired in parallel.

• I used SAE connectors for all but the first connection from the panels, which are the panel-attached MC4's. I have a short MC4<->SAE adapter cable on the portable panel side of the connection. The roof panel connects to an MC-4 junction box that is glued over the top of a hole in the roof.
• I used 10ga. wire throughout, including the SAE pigtails and 25ft. extension for the portable panel.
• I'm connecting the portable panel inside the van. I droop the portable wire out the back door and close the door, letting the wire get pinched by the door gasket. I didn't want to mess with drilling a hole in the side of the van.
• To parallel the 10Ga. wires from the roof and portable panels, I either used double spade connectors (2 into one), or piggyback spade connectors, or terminal blocks.
• Where the portable panel connects in the van, I put an on/off switch and voltmeter, with the voltmeter on the panel side of the switch. I did this so that I know for sure the external panel polarity is correct before it's connected to the Victron.

It works.

Thank for the info. I realize with SAE polarity is a concern so will have my multimeter ready to roll.

[Jonesdds]

Originally Posted by booster

With two panels and one used only some of the time, you will need to be parallel wired, unless the controller auto switches input voltage for you. With a 50 ft difference in cable length, which for resistance is 100" of wire as both ways count, you would want to look at the resistance of your shorter wiring and then calculate from the charts just how big you would have to got to get the same resistance in the long wiring. If you don't, the long wiring will kill the output from that panel, I think.

Agreed on being in parallel. In parallel if the long wiring is an issue I believe it affects both panels output, correct? So doubly important to know.

I find it a bit strange it’s only 14 gauge out of the panel. Isn’t that already affecting output even with 10 gauge from there to controller?

Been a long time since Physics class in college but I think I can figure it out, I did get an A. One guy on the Facebook group of my trailer went with the 10 to 12 to 8 vs 10 all the way, for the cost savings I believe. The less the resistance to greater the output, correct?

[Jonesdds]

I've decided since the season is almost over I'm going to mount both panels on my roof using the Renogy drill free mounting system for my 100W panels. Love this system and I can still use my rack. VHB tape to mount it. I will use cotterless hitch pins to secure the panels so I can easily remove them in the future. I do want to see how I do with the two panels staying on the roof. Here's the mounting system.
https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

Two last things: I've installed the wiring to panels into my Victron controller with the correct polarity, I think. But, before hooking up I want to test. I'm thinking I'll power up the electrical system and use a multimeter to test the MC4 ends, if a get a positive numbers then I'll have figured it out. is this the correct way to go about this?

Also I'm using a NOCO 10 plugged into my shore power strip so that I can charge with shore power as well when able. I'm also using the Victron smart shunt and it's suggested all loads run through it. I'm running a line from it to my controller at the batt - spot, then from there to bus bar from the load - on the controller. Bus bar to fuse block. Some have suggested hooking the NOCO to the fuse block. This doesn't seem right to me but maybe so? If not what about to the smart shunt load side and the positive to the battery directly. What's the best, right way to do this.
And no chassis grounding is needed in this setup.

[SteveJ]

I didn't use the Victron shunt monitor but moat all of the other brands recommend using the negative cable for measuring.

Why the separate NOCO charger? I used a PD 4945 on my Roadtrek for charging and my current Safari Trek uses an old Heart 10 inverter charger. Both of these setups have played very well with the solar controllers, Renogy PWM on the RT and a SmartSolar Victron 100/30 MPPT on the Safari.

Also, if the solar controller is not mounted in the same climate as the batteries a Victron remote temperature sensor is desirable. It will communicate with the Victron Bluetooth network. It also gives a dead on voltage reading at the batteries instead of pulling the reading from the controller output.

Batteries used in both applications were " maintenance free" lead acid. A single group 29 Ever Start Max "deep cycle" in the RT and two Interstate group 31 "high cycles" in the Safari.

[Jonesdds]

Originally Posted by SteveJ

I didn't use the Victron shunt monitor but moat all of the other brands recommend using the negative cable for measuring.

Why the separate NOCO charger? I used a PD 4945 on my Roadtrek for charging and my current Safari Trek uses an old Heart 10 inverter charger. Both of these setups have played very well with the solar controllers, Renogy PWM on the RT and a SmartSolar Victron 100/30 MPPT on the Safari.

Also, if the solar controller is not mounted in the same climate as the batteries a Victron remote temperature sensor is desirable. It will communicate with the Victron Bluetooth network. It also gives a dead on voltage reading at the batteries instead of pulling the reading from the controller output.

Batteries used in both applications were " maintenance free" lead acid. A single group 29 Ever Start Max "deep cycle" in the RT and two Interstate group 31 "high cycles" in the Safari.

I’m not sure what the devices you mention are for charging. I do run the Victron remote temp sensor because my battery doesn’t have cold charge shut off. Set to 5c and don’t worry about it

[SteveJ]

Originally Posted by Jonesdds

I’m not sure what the devices you mention are for charging. I do run the Victron remote temp sensor because my battery doesn’t have cold charge shut off. Set to 5c and don’t worry about it

I mis-typed the PD(Progressive Dynamics) converter charger, it should be a 4645. It has the "Charge Wizard" as part of the unit.

The Heart Freedom 10 (Heart is now Xantrex(sp?)) is an inverter charger with a built in transfer switch.

These were on two different RVs.

[otr]

what vehicle are you mounting this on? I could share photos of my set-up on a 2000 RT 190, very similar solare with one removable panel, no holes in the roof, etc.