Question. In BS7671 what reg states about proving dead? Also about locking off?
Question. In BS7671 what reg states about proving dead? Also about locking off?
Returning to locking off, does anybody have much faith in dolly locks? It can be a real fiddle to get them to stay on in the first place and a sharp tug could easily remove one.
I can imagine that if a ladder slipped an outgoing device or even main switch (including the REC2 type of main switch in a box device) could be closed accidentally.
I can imagine that if a ladder slipped an outgoing device or even main switch (including the REC2 type of main switch in a box device) could be closed accidentally.
Unlike the traditional British 'up for off, down for on' most modern devices follow the European convention of up for on - so much less likely to be closed accidentally by falling objects. Not impossible perhaps, but reasonably unlikely.
One of the major flaws for testing for dead is that it doesn't take account of things changing with time - e.g. downstream of something on a timeswitch, or thermostat or even a second lightswitch somewhere out of sight (typical with 2-way switching) - pull the upstairs lighting fuse, "prove dead" then someone absent mindedly switches on the switch in the hall - which had a borrowed L from the downstairs circuit.
- Andy.
I can imagine that if a ladder slipped an outgoing device or even main switch (including the REC2 type of main switch in a box device) could be closed accidentally.
Unlike the traditional British 'up for off, down for on' most modern devices follow the European convention of up for on - so much less likely to be closed accidentally by falling objects. Not impossible perhaps, but reasonably unlikely.
One of the major flaws for testing for dead is that it doesn't take account of things changing with time - e.g. downstream of something on a timeswitch, or thermostat or even a second lightswitch somewhere out of sight (typical with 2-way switching) - pull the upstairs lighting fuse, "prove dead" then someone absent mindedly switches on the switch in the hall - which had a borrowed L from the downstairs circuit.
- Andy.
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