Megger RCDT320-EN-BS 1000mA RCD tester covers a wider supply voltage range of 50V to 290V, allowing use with centre-tapped 110V supplies. It incorporates ramp testing, for RCD tripping current measurement, and the unique Megger auto sequence test feature, which saves time by allowing the tester to conduct all the RCD tests, and to store the results while the operator stands by the RCD, resetting it as appropriate.