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Test Procedures
Raychem-IM-H58067-IceStopRoofGutterDeIcingCOM-EN 18/01
Capacitance Method
This method uses capacitance measurement (nF) to
approximate the location of a fault where the heating
cable has been severed or a connection kit has not
been connected.
Record the capacitance reading from one end of the
heating cable. The capacitance reading should be
measured between both bus wires twisted together
(positive lead) and the braid (negative lead). Multiply
the measured capacitance with the heating cable’s
capacitance factor as listed in the following example:
Example:
Capacitance measurement = 42.2 nF
Capacitance factor = 6.0 ft/nF for all IceStop cables
Fault location = 42.2 nF x 6.0 ft/nF = 253 ft (77 m)
The ratio of one capacitance value taken from one
end (A) divided by the sum of both A and B (A + B)
and then multiplied by 100 yields the distance from
the first end, expressed as a percentage of the total
heating cable circuit length.
Fault location: C =
A
x 100
________
(A + B)