The shorting pulley rim is manufactured from a special copper alloy that has high electrical conductivity and good wear resistance.
The insulating pulley is manufactured from resin bonded fabric which has good wear resistance and low thermal conductivity to minimise wire-to-pulley heat loss.
The pulleys are mounted on low friction, double row ball bearings to minimise the drag force (tension increase) on the wire as it passes through the preheater. Both pulleys are precision machined to ensure that uniform tension is applied to the wire, thus reducing SRL problems in data and telecommunications cable applications.
The preheater is powered from a 3-phase mains input, which is converted to a high-frequency supply by a specially designed inverter, the output of which is automatically adjusted to deliver the necessary power to maintain the required “Preset Temperature” regardless of wire size or production speed.
The preheater is fully protected against mains supply phase loss or brownouts.