Chauvin Arnoux CA 6549 [P01139713] 500V / 1000V / 2500V / 5000V Insulation Tester . The best overall model in Chauvin Arnoux's range of 6500 megohmmeters, this device includes everything found on the other meters in the range plus a few additional functions exclusive to this unit. This device is a multifunctional measurement tool that can be used to carry out measurement of insulation resistance, voltage, capacitance and leakage current across a wide range. It is a device that is made for use in evaluating high voltage systems and can measure insulation resistance up to 10TΩ, voltage up to 5100V, capacitance from 49.99F and leakage current up to 3000A. In addition to these standard measurements the CA6549 can also be used to calculate polarisation index (PI), dielectric absorption ratio (DAR) and dielectric discharge index (DD) in order to maintain testing accuracy when carrying out long term testing. The CA6549 also includes programmable alarms, built-in memory, a step voltage function which will adjust the test voltage automatically over a time period, programmable testing duration, R(t) graph, a smoothing function to make unstable readings stable and a reference temperature function.