Ground Mount with Adjustable Rear Leg

Philip C

I'm looking for a ground mount system with an adjustable rear leg that is rated for at least 120mph. Most systems are rated at either 90 or 100mph.

Any Ideas?

Thanks
Philip

niel

Re: Ground Mount with Adjustable Rear Leg

now this is interesting and i guess i can understand why you may want stronger mounts, but how sure are we that the pvs will survive 120mph winds as they don't post wind ratings on them? hail impacts are one thing, but constant high winds or gusts are another.
if in contacting the mount manufacturers that none of them can accommodate your requirements then you may need to have special ones made up.

Philip C

Re: Ground Mount with Adjustable Rear Leg

Typically most PV modules are rated for 50psf, even though this doesn't equate to an exact wind speed. When one takes the mounting method and environmental conditions, one can calculate a theoretical psf due to wind speed.

mike95490

Re: Ground Mount with Adjustable Rear Leg

A larger concern of 120mph wind, is the stuff it blows around at ground level. Chairs, strips of shingles, large trees, small cars. Most PV won't take that sort of impact.
Make a plan to cover them with plywood, or remove.

Philip C

Re: Ground Mount with Adjustable Rear Leg

That is a good point, does home owner's insurance cover a ground mount system?

Solar Guppy

Re: Ground Mount with Adjustable Rear Leg

Homeowners coverage will be limited or excluded for PV if its not part of the insured structure, if your doing ground mount you will need to be very specific on your coverage and may possible want a rider explicitly covering the ground array.

If you have 100+ mph winds, your PV's will be long gone, maybe the frames will remain but little else

Philip C

Re: Ground Mount with Adjustable Rear Leg

Living along the Gulf coast we will see winds exceeding 100mph, sooner or later

mike95490

Re: Ground Mount with Adjustable Rear Leg

I'd plan on a steel locking cable, and a pre-planed secure site to stack them. Trying to make a sail, not a sail, is silly.

solarvic

Re: Ground Mount with Adjustable Rear Leg

Solar Guppy wrote: »

Homeowners coverage will be limited or excluded for PV if its not part of the insured structure, if your doing ground mount you will need to be very specific on your coverage and may possible want a rider explicitly covering the ground array.

If you have 100+ mph winds, your PV's will be long gone, maybe the frames will remain but little else

When I insured my poletop solar the insurance insured them like big satelite dishes. They consider them added contents of my outbuildings and pole garage. I think the extra coverage was about $25 per year in Pa.

Dave Angelini

Re: Ground Mount with Adjustable Rear Leg

My policy says that the tracker (or top of pole mount) must be adjustable to horizontal for high wind events that are forcasted. We just had mountain winter storm warnings for high winds just last week.

Check your mounting bolts because in my experience they are the weak link. Just amazing how a slightly low torqued 5/16 hardware can completely come unfastened in 70 knots. We do see 100 knots up on the crests but I sure as h*ll would not want to live up there.

Philip C

Re: Ground Mount with Adjustable Rear Leg

Just an Update

Schletter has an adjustable ground mount system rated at 140mph + wind zones. The only problem here in the states, there is a 12Week lead time.

Any other suggestions would be helpful

Thanks,
Philip

BB.

Re: Ground Mount with Adjustable Rear Leg

I would guess stress on the frame work goes with the square of the wind speed:

• 120mph^2 / 90mph^2 = 1.78x forces

So, you would need almost 2x as strong as structure to hold the panels...

You can use various hand books too calculate wind loading (see this website for some examples).

Or look at hiring a structural/civil Professional Engineer (PE) to do the design for you with available hardware.

-Bill