I am running several new outdoor circuits using PVC conduit and PVC J-boxes. The circuit will involve transitions from interior house wiring NM to THWN and back to underground NM.
When NM enters PVC conduit or a PVC box, is cable clamping necessary? If so, why?, and what type of clamp do I use, I can't find any clamps designed for use with PVC conduit or PVC boxes.
One person told me clamps are not needed where NM enters boxes and just to use silicone where underground NM enters conduit to keep moisture bugs and dirt out. Another person told me clamps are required and to use metal conduit clamps screwed into PVC threaded adapters. Someone else told me you can't use any metal fittings on a PVC system because there is no mechanism for grounding.
Help!
When NM enters PVC conduit or a PVC box, is cable clamping necessary? If so, why?, and what type of clamp do I use, I can't find any clamps designed for use with PVC conduit or PVC boxes.
One person told me clamps are not needed where NM enters boxes and just to use silicone where underground NM enters conduit to keep moisture bugs and dirt out. Another person told me clamps are required and to use metal conduit clamps screwed into PVC threaded adapters. Someone else told me you can't use any metal fittings on a PVC system because there is no mechanism for grounding.
Help!