Originally Posted by Reyman
I cut the cable every second time I do a big job with those hedge trimmers. It's not dangerous because the trimmers are usually well insulated from the cutting arm.
You also probably have an earth leakage circuit breaker on your fuse board which will cut the power very fast if the live and neutral current differ.
An ELCB will trip for an earth fault. You need an earth wire in the circuit to operate the ELCB. Most of those hedge cutter gizmos are double insulated and have no earthing connection.
It is possible to cut a cable and for the supply end of it to be still live. If you pick it up you get zapped by the mains. A woman was fatally injured a few years ago in the UK in just such a scenario. The chances of this event are freaky but you don't want to be the one.
To trip the ELCB you probably need to cut a three core supply flex and to cross live with earth.
If you manage to cross live with neutral the ordinary circuit breaker for that circuit should trip as you will have created a classic short circuit condition.
Best always to use power tools and the like with a plug in RCD that pops into the socket. However, do not always assume that the RCD has actually worked. If you cut a cable proceed with caution and assume the wiring is actually unsafe until you know otherwise.
Damaged cables should always be replaced. Tape jobs are woefully inadequate and dangerous repairs. Alternatively, a safe repair for a cut cable is to place a proper male/female connector in the cable at the point where the cut happened. For God's sake remember to put the female side of the connector on the supply side of the cable and never the other way around otherwise you get live pins that you can touch. Alternatively, if you do not fully understand what you are doing get it done by a qualified person as life is too precious !!