AS/NZS3760 requires RCDs to be tested including where necessary fixed RCDs.
An RCD (Residual Current Device) is basically a very quick switch that operates if an item it supplies with electricity becomes unsafe. RCDs are everywhere now so it is common for PATs to have an RCD tester in-built – you can still buy stand alone RCD testers and PATs that do not have an RCD built- in.
It is unlikely that people testing will not need an RCD tester so when purchasing a new PAT it obviously makes sense to add this in.
As a minimum an RCD tester must measure trip time ie disconnect time when they are tested at the rated trip current. This will be in milliseconds – I second = 1000 milliseconds. Commonly they will disconnect or trip in less than 25 milliseconds hence the need for a very accurate measuring device.
- The Sonel MRP-210 is an innovative RCD Tester designed to test AC, A and B type RCDs. Features Testing of general, short delay and selective RCDs for the rated current values IΔn =10, 30, 100, 300 and 500 mA. Simultaneous measurement of tripping current IA and disconnection time tA, for currents 0,5IΔn, 1IΔn, 2IΔn ,...
- The MPI-502 from Sonel is a multifunction earth loop impedance and RCD tester combination in one compact unit, making it possible to test both loop impedance and RCD trip time and current without the need for separate instruments. Features: Earth loop impedance and RCD testing in one handy unit Non-tripping of the RCD when earth...
- $290.00 excluding GST$333.50 Including GSTFeatures Fully programmed operation Accurate digital read out of tripping time and Current 450ms readout for testing latest delay action breakers Two LED lamps give quick check for correct wiring Compact, lightweight and simple to operate Zero cross circuitry permits testing at 0° and 180° portion of sine wave Size(HxWxD): 200mm x 70mm x 45mm...