RCD Testing Assessment Questions And Answers Verified Principle And Issues.

Under which TWO circumstances are the operating times of RCD's required to be tested? - correct answer Where the RCD is used for: 1. Fault Protection against indirect contact (the 1 x test) OR 2. Additional Protection against direct contact (the 5 x test) For each test, why does the RCD need to be tested on the positive and negative half cycles? - correct answer Because each half cycle may produce a different test result If testing on each half cycle produces a different test result, which test result is recorded? - correct answer The longer operating time Prior to RCD testing which other test MUST have been carried out? - correct answer Earth Fault Loop Impedance Why must EFLI testing have been carried out before RCD testing? - correct answer To prove there is a satisfactory earth path for the test current to flow down If an RCD test was performed on a circuit without a satisfactory earth path, what danger would occur? - correct answer The risk of electric shock to anyone in contact with exposed/extraneous conductive parts during the test. Which test instrument is used for RCD testing? - correct answer An RCD tester Where is the RCD test carried out? - correct answer On the load side of the RCD Between which conductors is the RCD test carried out? - correct answer Line and cpc What should be done with any loads on the circuit prior to carrying out the test. - correct answer They should be disconnected What precaution should be taken with people and livestock during the test? - correct answer They should be prevented from touching exposed and extraneous conductive parts of the installation? Under what circumstances is the risk of electric shock during RCD testing at its greatest? - correct answer When the EFLI of the circuit approaches the maximum allowed When tested with 50% of it's rated current how should the RCD react? - correct answer It should not trip When tested with 100% of it's rated current how should an older RCD built to BS4293 react? - correct answer It should trip within 200mS When tested with 100% of it's rated current how should a newer RCD built to BSEN61008 react? - correct answer It should trip within 300mS When tested with 100% of it's rated current how should a socket outlet with a built-in RCD react? - correct answer It should trip within 200mS What is the maximum rating of an RCD, if it is to be used for Additional Protection against direct contact? - correct answer 30mA When tested at 5 times it rated current, an RCD use for Additional Protection must trip within what time? - correct answer 40mS Which other test follows the electrical tests on an RCD? - correct answer A mechanical check that the built-in test button works Under which circumstances will the built-in test button of an RCD NOT work? - correct answer If the RCD is not energised