| 摘要 |
A method of testing a fuse (12) in apparatus for monitoring electrical insulation (8) surrounding first and second electrical conductors (3 and 4) in a cable (2), the fuse being connected to said conductors, comprises: applying an electrical signal, with respect to a reference, to said fuse from a source (1); obtaining a value (IR) for the resistance of said insulation with respect to said reference; determining if said resistance value is greater than a fuse test resistance threshold and, if it is, causing the application of the signal to cease; and monitoring the decay of said signal to determine if the time for it to decay below a set value exceeds a set time limit, indicative of the fuse being satisfactory, or is less than said limit indicative of the fuse being blown. 0)J L r LL z 0iwO __ ___ co |
