RCD Research
RCD - Reliability Investigation
ERA Technology Ltd is conducting the second phase of the research into the reliability of residual current devices (RCDs) on behalf of the Council.
ERA has completed the laboratory-based testing to determine the effects of various domestic loads on the operating characteristics of a range of RCDs. This initial work was carried out to help determine whether the field testing should be carried out with or without downstream loads connected.
In order to assess the effect, if any, of connected loads on the operation RCDs, ERA purchased a number from different manufacturers. These were connected to various loads, some of which simulated leakage currents from equipment typically found in homes.
All the units tested were purchased as new, apart from one which had been in service. In summary, the findings from this investigation were that:
- Although for the majority of RCDs tested there was no appreciable difference in their performance, three of the units did demonstrate different operating characteristics when loads were connected.
- The presence of leakage currents from equipment in homes where ERA would be carrying out on-situ testing could have an effect on the operating times of the RCDs.
For the purposes on the in-situ testing therefore, it was decided that all circuits controlled by the RCD, except the circuit being used for the testing, should de-energised, and that any loads connected to the RCD circuit should be switched off.
A full report detailing the findings and conclusions of this laboratory-based testing can be viewed here.
