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Longline (HTS3FM)

Products > Series (Longline) Heaters > Longline (HTS3FM)

Product Features


Longline (HTS3FM) is a series resistance, three phase constant power heating cable used for freeze protection or process temperature maintenance of moderately long pipelines up to 2km, in safe or hazardous areas. A typical application is the temperature maintenance of crude or fuel oils in above ground or buried transfer lines. 

Longline (HTS3FM) minimises the number of electrical supplies needed and so minimises supply cabling and distribution equipment costs. Circuits are often fed at the pipe ends only.
Heating conductors are sized to produce the desired heat output for the circuit length required. The Longline (HTS3FM) heating cables are connected directly to the 3 phase mains voltage or to a step-up transformer.
The large heated surface of Longline (HTS3FM)’s flat foil construction results in lower operating temperatures than equivalent round conductor constructions thereby improving safety and system life. The high efficiency produces high power capability up to 50W/m.
Longline (HTS3FM) heating cable may be straight traced or spiral traced to above ground pipes. The insulation material is silicone rubber ensuring the cable is very flexible. For buried lines, cables are usually drawn into channel raceways within a pre-insulated pipeline system. The installation of Longline (HTS3FM) is quick and simple and requires no special tools.  See Product, Application and Documentation Links below.
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Product Specification

Maximum Withstand Temperature 200°C (392°F)

Longline (HTS3FM) is available in outputs upto 50 W/m as illustrated on the graph to the right.  The graph shows the nominal power output at 480V 3 phase, 1000 metre long pipe with 3 x 4mm² conductors, when installed on insulated metal pipes.  The output of the cable is varied by changing the voltage or the size of the conductors.  Click on the graph to see a larger version.

  Maximum Withstand Temperature

HTS3FM-xS 200°C (392°F)
HTS3FM-xF 200°C (392°F)

  Maximum Energised Temperature HTS3FM-xS 200°C (392°F)
HTS3FM-xF 200°C (392°F)
  Minimum Operating Temperature -40ºC (-40ºF)

Power Supply

 Upto 600V 3 Phase


Max Conductor Size

4 x (0.3mm - 1.5mm)

  Click on the graph to see a larger version.
Nominal power output  against pipe temperature


  Minimum Installation Temperature

-40°C (-40°F)


Maximum Workpiece Temperatures (°C)
Nom Output (W/m) T6 T5 T4 T3 T2 T1 Safe
HTS3FM-xS 10 57 73 112 181 200 200 200
   20 37 53 93 166 180 180 180
   30 - 31 73 152 157 157 157
   40 - - 51 127 127 127 127
   50 - - 27 92 92 92 92
HTS3FM-xF 10 57 73 112 181 200 200 200
  20 37 53 93 166 180 180 180
  30 - 31 73 152 157 157 157
  40 - - 51 127 127 127 127
  50 - - 27 92 92 92 92
Surface temperature limits in acordance with EN50014.
Approvals and Certification
HTS3FM CML 19.0132X
HTS1F MЮ62 B 01122/19
Product and Application Datasheets
HTS3FM Datasheet
SK-HTS3FM Instructions
TK-HTS3FM-6 Instructions
TK-HTS3FM-10 Instructions
TK-HTS3FM-16 Instructions

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