Power-Limiting Heat Tracing Technology
nVent RAYCHEM power-limiting heating cables (VPL) are designed for freeze protection and process temperature maintenance requiring high power output and/or high temperature exposure.
nVent RAYCHEM parallel heat trace cables are parallel heaters formed by a coiled resistor alloy heating element wrapped around two parallel bus wires. At a fixed distance, the insulation is removed from the alternate bus wires to form a heating zone.
The positive temperature coefficient effect (PTC) of the heating element reduces power output as ambient temperature increases. This effect allows the VPL power-limiting cable to be overlapped by reducing the temperature of the heating element at the overlap points.
nVent RAYCHEM power-limiting heating cables feature
- Maintain temperature e up to 455°F (235°C)
- Exposure temperature up to 500°F (260°C)
- Circuit lengths up to 450m from a single power source
- Supply voltage up to 480 VAC