Self-regulating, Completing the installation, Temperature control – Thermon FLX User Manual

Page 5

FLX

Self-Regulating

Completing the Installation . . .

1. Begin final cable attachment by securing the end-of-circuit

termination kit and working back toward the power supply.
• Flexible heating cables are to be installed using attachment

tape. Circumferential bands of tape should be installed at
12” (30 cm) intervals to keep the cable in proper contact
with the pipe. Refer to Table 2 below to calculate the num-
ber of rolls of attachment tape required based on the pipe
diameter

• If applicable, refer to installation details provided with the

project drawings or contact Thermon for additional infor-
mation regarding installation.

2. In addition to the circumferential tape requirements, a

continuous covering of aluminum foil tape may be required
when:
• Spray or foam urethane

thermal insulation is applied.

• Heat tracing nonmetallic piping.
• Design requirements dictate the use of aluminum tape to

improve heat transfer.

3. Complete splice connections (if required) in accordance

with the installation instructions provided with the splice kit.

4. Install power connection kit in accordance to the detailed

installation instructions provided with the kit.

5. Before making power connections, repeat the megger test

with at least a 500 Vdc megohmmeter (megger) between
the heating cable bus wires and the heating cable metallic
braid. IEEE 515.1 recommends that the test voltage for
polymer insulated heating cables be 2500 Vdc. The mini-
mum acceptable level for the megger reading for any
polymer-insulated heat tracing cable is 20 megohms.
(Record 2 on Cable Testing Report)

Heating Cable vs. Sensor Location

Temperature Control . . .

1. When a line sensing controller is specified, the sensor should

be placed at least 90° around the circumference from the
heating cable, or at least 2" (5 cm) from the cable.

Tape

Length

Pipe Diameter in Inches

½"-1"

1¼"

1½"

10"

12"

14"

16"

18"

20"

24"

30"

36 yd

130'

115'

110'

95'

75'

65'

50'

40'

35'

30'

26'

23'

21'

19'

16'

13'

60 yd

215'

195'

180'

160'

125'

105'

80'

65'

55'

50'

43'

38'

35'

31'

27'

22'

Heating Cable

(Typical)

Temperature

Sensor

Table 2: Attachment Tape (Value Represents Approximate Linear Pipe Length Allowance Per Roll)

Ambient Sensing Thermostat

End Termination

Power Connection

L2/N

Ambient Sensing Control Connection

Temperature Sensor

End Termination

Power Connection

L2/N

Heating Cable

Pipewall Sensing Control Connection

Heating Cable

3. When using an ambient sensing temperature controller, the

mounting location should be representative of the coldest
region, and the sensing element should not be exposed to
direct sunlight or any additional heat source.

Notes . . .
1. Table 2 assumes circumferential bands every 12” (30 cm) along the length of the piping.
2. Verify exposure temperature of heating cable versus curing temperature of insulation.

2. For pipewall sensing thermostatic control, the heating circuit

is to be connected in series with the control contacts as
shown in illustration below. The pipewall sensing thermostat
may require more than one support point.

90°

Optional Third

Heating Cable

Optional Second

Heating Cable