FWIW, I mounted my Renogy panels with the drill-point lags that came with the panels. I have no HVAC ducting in my ceiling, and gravity takes care of wiring, etc. above the ceiling so the lags pose virtually no risk to wiring above the ceiling so long as you keep a bit of distance from things like your roof vent/fan.
- Install the charge controller so that it is connected to your battery bank and to the gland on the roof...if you have solar already, this should already be done. You want the charge controller connected to the battery before you connect the panels to the charge controller. See instructions with charge controller.
- Layout the panel(s) location.
- Assemble panels/brackets.
- Mark drill holes with a Sharpie.
- Assemble wiring. In my case, 4 panels in parallel, so I had 2 panels in parallel with adapter/connector X 2 plus a 3rd parallel adapter to join the two sets. I paired up each set of two panels, fiddle farted around with the wire to dress it out as I wanted...all connections under the panels, then paired up the two sets...also with connector and wires under the panels.
- Place the panels to match the Sharpie-marked drill holes and double check the wiring is tucked away without causing issues.
- Connect to the gland or add a parallel connector, or wire in series, to your existing solar panel-to-gland connecting wire per your design.
- Test the system prior to anchoring panels to the roof.
- Brand new, premium grade drill bit about two sizes smaller than the lags to drill pilot holes through the roof membrane and into the roof sheathing below. This part seems redundant with the drill-point lags, but I didn't want to risk snagging and tearing my EPDM roof membrane with a faulty drill-point on one or more lags.
- Clean the roof membrane where the brackets will connect using something like 90% rubbing alcohol. It's gentle, but it cleans, and it dries very quickly.
- A tiny bit of Dicor caulk in the pilot holes and on the lag threads.
- Butyl Tape under the brackets between the brackets and the roof. This stuff is sticky and squashes out when you snug the lags.
- Fasten the panels to the roof. DO NOT OVERTIGHTEN THE LAGS. Jayco already confessed to sheathing the roof with "plywood" that is LESS than 3/8" thick. 3/8" = 0.375. They said 0.34" sheathing. Feel free to use a drill or impact driver to drive the screws in to ALMOST SNUG, but then use a hand nut-driver to finish the job. Some of the biggest problems in RVs are screws stripped out due to using power tools to drive the home. Hand tighten ONLY.
- Slather on a generous amount of Dicor Self Leveling Sealant over each bracket and lag.
It appears the water's over the dam on your purchase of the 200 watt add-on panel. Perhaps you can still return it and get 2 or 3 100 watt panels to take full advantage of your charge controller, which is likely to be able to handle 400 watts (30 amps). Your call on that.
Here is a primer for mixing and matching panels of different watts outputs...and issues with mixing voltages. Make sure that your existing panel is nominally 18 volts and that your 200 watt panel is also nominally 18 volts. If they are a mismatch, read on about issues that causes in the Bouge documentation. I found
this Renogy 200 watt panel, and its voltage is nominally 18 volts (19+). This would likely be a good match for your current 100 watt panel.
If you are stuck with a 200 watt panel that puts out more like 36 volts, you could add a second 100 watt panel in series with your current panel to raise the voltage to about 36 volts.
My installation is 4 years old. It's as secure and dry as any other factory roof penetration...probably more so, because my work is far more meticulous than that of an RV assembler.
__________________
Jim Moore
SW Colorado - 4-Corners Area
2020 Jayco X213 Rear Slide
2006 RAM 1500 with Firestone Airbags No WDH
400 watts of solar on the roof & 200 watt of suitcase 2 x GC2 batteries
Starlink Gen-3 running from a 500 watt pure sinewave inverter
Boondock almost exclusively on the shores of
Lake Vallecito