Loop and RCD testers can work in tandem, with an RCD (Residual Current Device) capable of breaking an electrical circuit before it causes harm, whereas a Loop Tester is a quick, convenient and highly specific method of evaluating an electrical circuit for its ability to engage protective devices (circuit breakers, fuses, Ground-fault circuit interrupter).
The primary reason for earth loop impedance testing is to verify that if a fault occurs in an electrical installation, sufficient current will flow to operate the fuse or circuit breaker protecting the faulty circuit within a predetermined time. The aim is to make sure that the circuit is disconnected fast enough to prevent overheating and possibly a fire.
With a single-phase circuit, the device monitors the difference in currents between the line and neutral conductors. This life-saving device, designed to prevent you from getting a fatal electric shock if you touch something live, (e.g. bare wire), offers a level of personal protection that ordinary fuses and circuit-breakers cannot provide.
RCD is a generic term applied to a family of products which open automatically in response to a residual current equal to or greater than the RCD's rated residual operating current.
An RCCB differs from an RCBO in that the RCBO will additionally respond to over current conditions whereas the RCCB will not respond to such conditions. The term SRCD applies to an RCD which is an integral part of a socket outlet or which is fitted in a box immediately next to a socket outlet.
RS have a comprehensive range of Loop and RCD Testers for a multitude of applications, from market-leading brands such as Megger and our very own brand RS PRO. RS have on hand technical advisers that can provide you with vital information not only on the product, but on our calibrated service. All of our products are available for next day delivery.