Thermon Electric Heat Tracing - Manual (Page 4)

Electric Heat Tracing
Proposed Power
Connection Location
Cable Allowance for
In-Line Heat Sinks
Pipe Support
Proposed End-of-Circuit
Location
Illustration C: Temporary Installation
Notes . . .
1. Termination kits to fabricate a heat tracing circuit are not
addressed in detail in these installation procedures. Refer
to installation instructions included with cable termination
kits or contact Thermon for specific instructions to
fabricate heating cable.
Before Installing Cable . . .
1. Be sure all piping and equipment to be traced is
completely installed and pressure tested.
2. Surface areas where heat tracing is to be installed must be
reasonably clean. Remove dirt, rust and scale with a wire
brush and oil and grease fi lms with a suitable solvent.
Initial Installation . . .
1. Locate the cable on the lower quadrant of the pipe at the
4 or 8 o’clock position. If accessibility is a problem the
cable may be installed at the 10 or 2 o’clock position.
Temperature sensor should be located at least 90° from
all heating cables. Refer to Illustration B for Heating Cable
vs. Sensor Location.
2. Begin temporary installation at the proposed end-of-
circuit location and lay out heating circuit on the pipe,
allowing extra cable for the power connection and for
any splice locations
1 . Refer to Illustration C for temporary
installation.
3. Make heating cable allowances for valves, fl anges, elbows
and supports as per the applicable drawings and table on
pages 5 and 6 of these installation procedures.
Upon Receiving Cable . . .
1. Upon receiving heating cable, check to make sure the
proper type and output have been received. All fl exible
cables have the catalog number, voltage rating and watt
output printed on the jacket.
2. Visually inspect
cable for any
damage incurred
during shipment.
The heating cable should be
tested to ensure electrical integrity
with at least a 500 Vdc megger
between the heating cable bus wires and the heating
cable metallic braid. IEEE 515 and EN-IEC 60079-30
recommend that the test voltage for polymer insulated
heating cables be 2500 Vdc. Minimum resistance should
be 20 megohms. Connect the positive lead of the megger
to the cable bus wires and the negative lead to the
metallic braid.
(Record 1 on Insulation Resistance Test Page 9 and 10)
3. Store in dry location.
3
Single Cable Installation Dual Cable Installation Triple Cable Installation
Heating Cable
(Typical)
Pipe Wall
Temperature Sensor
(Typical)
45º
45º
45º 45º 45º
90º
Illustration B: Heating Cable vs. Sensor Location
45º
45º 90º