Heater Cable Information
Standard design heater cable specifications:
- Sheath alloy 600 or equivalent with an annealed bright surface finish
- Insulation high purity MgO 99.4% minimum and a 70% nominal compaction density.
- Conductor(s): either single (1) or dual (2) nickel / chrome alloy wire(s) with an electrical resistance of 620 to 650 ohms/circular mil. foot. The change in resistance at 2000 degrees F is less than 14%.
- Room temperature insulation resistance for mineral insulated heater cable over .062″ outside diameter is 10,000 megohms at 500 vdc. For cable with a smaller outside diameter than .062″, the resistance is 5000 megohms at 50 vdc measured from wire to wire or wire to sheath.
- The mineral insulated heater cable may be coiled around a mandrel that is 4 times the sheath diameter (tighter coils or bends are not recommended if maximum life is to be expected).
The safe watt density for mineral insulated heater cable, in still air applications, is 30 watts per square inch. Higher watt densities are possible in certain applications.
Maximum recommended applied voltages:
|.032″ to .040″||50*|
|.062″ to .092″||120*|
|.125″ and larger||240*|
*In some applications this voltage may vary.