These cables, to a BBC specification but updated to low fire hazard (LSOH) standards, have single solid conductors, twisted in pairs and overall foil screens with drain wire. They are suitable for permanent installations where screens are terminated on a bus arrangement, such as jackfields and IDC type blocks. They have a relatively low impedance (they were designed before digital audio was invented) and are not suitable for digital audio circuits.
||PSN10/3M (KSM-LFH5), PSN20/4M (KSM-LFH10), PSN40/2M (KSM-LFH20), PSN50/3 (KSM-LFH25), modified to low fire hazard design (LSOH)
||Twisted to form pairs, than laid-up with overall Melinex tape
||1/0.5mm (0.2mm²) tinned copper wire
||Polyethylene. For colours see technical data section
||Aluminium or aluminium/polyester tape
||1/0.5, (0.22mm²) tinned copper
||Low smoke zero halogen material, cream
||6.3mm (KSM-LFH5), 7.6mm (KSM-LFH10), 10.2mm (KSM-LFH20), 10.8mm (KSM-LFH25)
||4.7kg/100m (KSM-LFH5), 8.4kg/100m (KSM-LFH10), 15.1kg/100m (KSM-LFH20), 17.0kg/100m (KSM-LFH25)
||Available in any multiple of 1 metre
'LFH' is a registered trademark of Canford Audio Limited.