Don't always trust tools!

[wildebus]

So I was making a couple of Auto Transfer Switches today ....

Made the cables. Prepped the special boxes. Wired it all up.
Plugged in the first one to test.... All good, plug in tester gave me left and middle lights on which meant all good.
Plugged in the second one ... Plug in tester gave me just the middle light (this meant open neutral even though I had a good voltage. very odd).
Took box apart, meter on it checking all cables etc. Can't see any problems and all looks right
Looked at tester again - the left LED light was slightly darker than the other two. Plugged into normal sockets - only middle light on. B*****y tester left LED had only gone and broken between testing the first box and second box. What is the chance of that happening!? Wasted much to much time not testing the tested after it reported good just seconds before


Moral of story? Plug-in Testers to save time can end up wasting more time!

 

[Pudsey Bear]

Who tests the tester issue.

I sometime need to by a spirit level or a temp gauge and you only have to look at them on the shelf to see some are absolut rubbish, levels are okay as they are the simplest to test so no need to compare them, but temp gauges can be miles out, I bought four outside ones for home a few weeks ago, had to return them as they were several degrees apart from each other in the same location.

 

[MarkJ]

You could do what aeroplanes do: have three testers and take the majority verdict!

 

[trevskoda]

Who tests the tester issue.

I sometime need to by a spirit level or a temp gauge and you only have to look at them on the shelf to see some are absolut rubbish, levels are okay as they are the simplest to test so no need to compare them, but temp gauges can be miles out, I bought four outside ones for home a few weeks ago, had to return them as they were several degrees apart from each other in the same location.

You can open most and adjust a small screw/pot inside to balance.

 

[Pudsey Bear]

You can open most and adjust a small screw/pot inside to balance.

Shop keepers tend to chuck you out for that, and it would void any warranty.