Right side of a Manufactured House (MH): Outside Pedestal with a 200 amps disconnect and two 20 amps breakers for the septic pump and other. Inside left side has a 200 amps service panel. New large garage/storage built at the left side of the MH, wood frame but all metal siding (mobile home metal type). Garage/storage separated about 10 from the MH and NO metal connections between.
Plan: Install a 100 amps breaker in the inside 200 amps service (plenty of room) and run a feeder to this garage/storage to a 100 amps sub-panel with a 100 breaker disconnect, this sub-panel will supply lighting, general receptacles, welding machine receptacles and others.
Situation: Because I am donating all labor and materials I would like to use some material that I have. I have a spool of AWG THHN 4; the ambient temperature is under 86 F as it is in the country in WA area (raining a lot) and I will install it in PVC 80 conduit buried 18 the 10 plus between the buildings, and both risers of this PVC 80, to the service panel and to the sub-panel will be protected. I will run 4 conductors (marking one green and another white). The neutral and ground will be un-bonded (no tied) at the sub-panel and I will install at the ground connection a bare 4 AWG (I have a spool of) to 2 ground rods (have 1 in stock).
Questions: (I am not too familiar with manufactured and metal building attachment)
I think I need to bond this metal siding in any way
Will bonding the four walls at each corners be effective?
Or installing Flexible Metal Conduit (FMC) for the fixtures/receptacles will be enough as I can install them on those siding?
Can I use this AWG 4 for this 100 amps service?
Should I need two rods?
Is there a 100 amps 4 conductors underground cable assembly that I can use without conduit?
Does the above plan make sense?
Any opinion/recommendation is greatly appreciated
