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Mike, Master Electrician
Category: Electrical
Satisfied Customers: 1425
Experience:  Licensed Master Electrician - OnQ Certified Data Voice Audio Video Installer
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How do I properly test a single phase thhn conductors in pic

Customer Question

How do I properly test a single phase thhn conductors in pic conduit? The circuit is connected to electric heat Mat for a driveway which already tested correctly but we want to check the 2 #10awg conductors feeding the heat mat.
Submitted: 1 year ago.
Category: Electrical
Customer: replied 1 year ago.
When check for continuity but now we want to check the insulation using a megger
Expert:  ProGrade replied 1 year ago.

Welcome to

Assuming that a ground wire is included in the circuit, disconnect all three conductors on both ends then connect L1 to the ground wire at the load end. Using a multimeter set to read continuity/ohms, get a reading between the ground wire & L1. Disconnect L1 from ground, connect L2 to ground and get a reading. Both reading some should be approximately the same (within the tolerance of the meter? , if one is much higher than the other or open, that conductor is defective and the wire would have to be pulled out and replaced with a good wire.

How long is this run? What voltage is the mat rated for? What is the wattage rating of the mat? Thanks Ken

Expert:  ProGrade replied 1 year ago.

Any progress, any questions? Thanks