This may belong in another forum.You have a jacuzzi tub in a bathroom,residential.One situation has copper pipes throughtout the house and the other situation has all plastic plumbing EXCEPT the fuacets on the jacuzzi,copper.By code,INCLUDING the lug on motor,what is the grounding procedure here?Bouncing across state lines here and trying to keep alot of inspectors happy?Latest fella wanted one from service to motor only in situation number 2.
680.74 requires metal piping systems and grounded metal parts in contact with the circulating water to be bonded together. If there are no metal pipes, then no bonding is required. You are making an equipotential grid. Never is it required to bond a hydromassage bathtub to the panel or the service. NEVER!!!!!!
That said, it is still required to include an equipment grounding conductor with the branch circuit conductors feeding the motor, and that conductor is bonded inside the motor to any metal parts. But no additional bonding to the panel is required.