Chauvin Arnoux CA 6541 [P01138901] 50V / 100V / 250V / 500V / 1000V Insulation & Continuity Tester. The CA 6541 Megohmmeter is a high-performance 50V to 1kV digital insulation tester that supports the most demanding site conditions and is ideal for qualitative insulation analysis. The CA 6541 megohmmeter is a micro-processor-controlled unit that is equipped with highly advanced functions for measurement of insulation up to 4TΩ, AC/DC voltage, continuity at 200mA, resistance and capacitance. The 6541 mega ohmmeter can automatically calculate the polarisation index (PI) and dielectric absorption ratio (DAR) which can be used to qualify the quality and ageing of insulation. The CA 6541 HV insulation tester employs time-controlled testing to give a better understanding of the quality of the insulation. When a programmable time-controlled test has begun, the CA6541 automatically samples and memorises the insualtion values at a rate specified by the user. A smooth function is also available for when the measurement values are unstable. For every measurement function, a high or low alarm threshold can be stored which will be triggered when exceeded.