I am installing ET Solar panels (ET-P660230B) on Unirac HD rails using top-mounted clamps. The ET installation manual recommends the clamp bolt should be torqued to 8-10 Nm (6-7.3 ft-lbs), but the Unirac manual recommends a torque value of 15 ft-lbs.
I would like to use the higher value to insure the panels are secure in high wind conditions but I do not want to risk damage to the modules. Any thoughts?
Comments
Manitou,
You will not damage the module. The frame that is being clamped is in compression and very strong. As long as the module is seated flat on level rail, proper torque on the clamp bolt will not hurt it.
You will, however, gall the stainless bolts or bend the clamps if you over-torque. Many installers go with the lighter torque since it is very easy to damage or break the stainless t-bolts.
It's much more important to make certain that the modules are seated flat and square against the top of the mounting rails and that there are no wires, wire ties, or foreign objects between the modules and the rails. Also make sure that the top mounting clamps are seated completely on the modules and that they are not twisted - so that module spacing is exact.