Old paper-lead cables pose a big challenge when fault locating due to their different physical construction compared to modern solid dielectric cables. Instead of having to deal with carbon and air like in faulted XLPE- or EPR-insulated cables, PILC cables are made of lapped paper impregnated with mass or oil.Breaking down a fluid insulation medium, igniting and stabilising an arc in a fluid, and capturing useful fault traces with the radar is all far more difficult on paper cables than on solid dielectric cables. In particular, breakdown voltages of high resistance faults may be very high, and low resistance faults do occur significantly more often.To be truly effective on paper-lead cables, the fault location system used must have a high DC hipot, sufficient energy for cap discharge, and a modern TDR. With its 40 kV DC hipot, 2000 Joules at 32 kV and a radar with Multishot and de-attenuation features, the STX40 is well-equipped to be successful in finding faults even on PILC cables.