Punching the roof for solar on an 04 Hallmark Ute

[ardvark]

I have installed multiple solar systems over the years on RVs, but now have a Hallmark and want to do the same. Has anyone here installed solar yourself on a Hallmark. Doing it on a pop-top is a novelty for me and don't want to reinvent the wheel. If you punched your roof to run your cable, where did you punch it?

Thanks,

Steve

 

[Wandering Sagebrush]

Steve, check with Hallmark before you punch a hole. Some builders prewirefor solar!

 

[ardvark]

Thanks,

I can check, but I have been up on the roof. Nothing there but the AC unit and roof vent. If they prewired it is covered with the roof.

Steve

 

[ntsqd]

If it is pre-wired it is likely no larger than 10 ga. wire. Which I consider to be too small for much more than 100W. As it happens that is the default size for the MC4 connectors and I didn't want to re-invent that wheel. If/When I upgrade past our single 100W panel I'll be changing the controller to one that can handle 24VDC+ input voltage and going series rather than parallel with the panels.

I punched a hole in our Phoenix's roof. Phoenix adds a plate under the bolts for any roof rack that might be added later, I drilled thru that as it gave me something secure to bolt a waterproof junction box down to. I "bedded" the box on a ring of 5200 around the hole. Later someone here found & linked these:
https://www.amazon.com/dp/B0111RNZDY/_encoding=UTF8?coliid=IRWEETYFRJELA&colid=1WJFO5EAJMISV Which I'd really rather have instead.

 

[Wandering Sagebrush]

Thanks,

I can check, but I have been up on the roof. Nothing there but the AC unit and roof vent. If they prewired it is covered with the roof.

Steve

If there it would probably be terminated under the skin. You have to know the location before you drill.

Agreed that 10 Gauge is a bit small for best charging.

 

[ardvark]

I understand the impact of size and resistance on amperage. How about more on series versus parallel. I have always done parallel, but I know some folks do series. I understand the difference more voltage makes from series, but how about the real world effect on amperage at the batteries? Does it really make a difference i.e. has anyone demonstrated one to be better than the other?

 

[Wandering Sagebrush]

I understand the impact of size and resistance on amperage. How about more on series versus parallel. I have always done parallel, but I know some folks do series. I understand the difference more voltage makes from series, but how about the real world effect on amperage at the batteries? Does it really make a difference i.e. has anyone demonstrated one to be better than the other?

Check this thread... possible answers... http://www.wanderthewest.com/forum/topic/3887-ultimate-solar-thread/

 

[ardvark]

Didn't find it, although one thread had series i the title, it never explored the topic. I will search further, thanks.

Steve

 

[enelson]

Hallmark goes through a hole on the side of the Fantastic Fan frame. We order ours "solar ready" and wires were provided. I don't remember the details and sold the camper over a year ago.

 

[ntsqd]

Series vs. parallel, just in case:
W=V*I
Watts
Voltage (V)
Amps (I)

Watts is watts so the Power transferred is the same, but high amps / low(er) voltage needs large cables where higher voltage (within reason) / low(er) current works on std wire.
The hitch is that the solar controller has to be able to intake 24+ VDC and output a 12 VDC charging voltage. Not all can do that.

 

[JaSAn]

I understand the impact of size and resistance on amperage. How about more on series versus parallel. I have always done parallel, but I know some folks do series. I understand the difference more voltage makes from series, but how about the real world effect on amperage at the batteries? Does it really make a difference i.e. has anyone demonstrated one to be better than the other?

Cliff's Notes version.

Solar panels in parallel:
Each panel's output is independent of the other. If one is shaded the other panel is not affected.
Voltage remains constant, currents add. Higher currents necessitate larger wire to minimize voltage drop.
Can use either PWM or MPPT controllers. PWM converts excess voltage into heat.

Solar Panels in series:
Panel current outputs are not independent. If one panel is shaded the output of both panels is affected.
Voltages add, current is equal to the lowest panel output. Can get by with smaller wire with minimal voltage drop.
Requires MPPT. MPPT will convert higher voltage into additional current.

jim

 

[ardvark]

Thanks for the responses. What I was looking for was whether anyone had put meter to theory at the batteries and compared the current outputs, but I found it on Youtube.

Now I am trying to decide if I should simply swap panels between our fiver and TC depending on which one we are using. Normally we use the fiver less often so I would not have to make the swap often thus I have been researching brackets. I do think I each rig will have it own controller.

 

[meandmydog]

Ardvark, I'm late to your thread but if you still have questions I installed 2 100 watt panels on top of my 2003 Hallmark Ute. You don't need to drill any holes through the roof. You should route them under the A/C unit. You will have to remove it first. Run the wires inside the channel that hallmark has for the wires going to the A/C unit. I can post some pics if you want to see. I planned on posting a write up on here but never got around to it. Hopefully oyu already answered all your questions and got it all installed.
Dan