Is72100r r c d test label 130x60 pk100 s a vinyl roll industrial signs is72100r these labels state important this installation or part of it is protected by a residual current device which automatically switches off the supply if an earth fault develops it should be tested quarterly by pressing the marked 39 t 39 or 39 test 39 the wording then goes on to explain what to do if the device fails industrial signs is72100r r c d test label 130x60 pack of 100 s a vinyl roll