Chauvin Arnoux CA 6532 [P01140832] 50V / 100V Insulation & Continuity Tester. Chauvin Arnoux model C.A 6532 is a simple-to-use insulation and continuity tester designed for telecommunications applications. It is the instrument of choice for measurements on telephone lines by insulation testing at 50 V or 100 V. Its ΔREL function can be used to obtain the difference in resistance between two pairs of wires. The length of the line being tested is displayed automatically by programming the line capacitance in nF/km.