Test Procedures
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Insulation resistance criteria
A clean, dry, properly installed circuit should
measure thousands of megohms, regardless of
the heating cable length or measuring voltage
(0–2500 Vdc). The following criteria are provided to
assist in determining the acceptability of an installation
where optimum conditions may not apply.
All insulation resistance values should be greater
than 1000 megohms. If the reading is lower, consult
Section 10, Troubleshooting Guide.
Important: Insulation resistance values for Test A
and B; for any particular circuit, should not vary more
than 25 percent as a function of measuring voltage.
Greater variances may indicate a problem with your
heat-tracing system; confirm proper installation and/or
contact nVent for assistance.
Test B
Test A