Proving dead & safe iso on Economy 7

[NickD]

Does the neutral go though the teleswitch? if not it has potential for voltage. do a voltage check before u megger it

When I said check the supply side for live I meant L-E, L-N, E-N. Sorry, probably should have made that clear.

 

[Dave 85]

wtf is this sh**e ?
why cant you just turn off the main sw ?
it wont matter if the teleswitch is energised or not.
and as for pulling out tails and sticking in connector blocks ?? get a grip or just pack in electricals before you have an accident..

Once again you have well and truly hit the proverbial nail on the head Biff.
Your ability to always say what I seem to be thinking never ceases to amaze me!
"How do I prove a dead supply is dead"....what will they think of next...

 

[NickD]

"How do I prove a dead supply is dead"

And the Oscar for Best Performance In The Role Of Someone Not Actually Understanding The Question goes to...

(Although you may get a nod in the Deliberately Just Trying To Wind Me Up category too.)

It comes down to: how do you prove the main switch has done its job, if the supply to it is dead anyway at the time?

 

[Knobhead]

If in doubt connect to earth. Works for the LV side of a distribution transformer, just scale it down a bit.

 

[NickD]

If in doubt connect to earth. Works for the LV side of a distribution transformer, just scale it down a bit.

I suppose risking blowing the cutout fuse is better than risking blowing your mind.

 

[Stroppy]

Here's what I would do:

check the times that the eco7 will be on or on the boost period, and work when it will be well in the "off" period

isolate it with the switch, and if it seems to switch normally (doesn't feel 'crunchy' and makes a positive movement and clicks to off) trust that it has disconnected as it should do. (Come to think of it can't you take the top off this isolator and prove its operation with a continuity tester??)

if you're still terrified that it may energise unexpectedly, work as if it is live - ie use only insulated tools, safety spectacles (!), don't touch the shiny bits etc. Maybe prop your volt stick on the Line conductor so if it suddenly comes live it will beep at you.

 

[TaffyDuck]

4 pages on how to use a continuity tester. Will wonders never cease? What`s next, which end to I hold a screwdriver? or perhaps why does it hurt when I attach croc clips to my testicles? :45::45:

 

[Dave 85]

And the Oscar for Best Performance In The Role Of Someone Not Actually Understanding The Question goes to...

(Although you may get a nod in the Deliberately Just Trying To Wind Me Up category too.)

It comes down to: how do you prove the main switch has done its job, if the supply to it is dead anyway at the time?

If having isolated a dead ECO 7 board, tested for voltage and found none, tested continuity across the main switch in the open position and found none (which is surely obvious to anyone who has even the most basic understanding of electricity) you are STILL scared to work on said supply, then Im afraid you are very much in the wrong game my friend.

 

[bigbaddave]

Yebbut I don't like to think thoughts like "well it's obvious" around safe isolation.

And with due respect I don't think it is that obvious because mere loss of continuity at closure doesn't prove the airgap will withstand the supply voltage. Hence my suggestion of actually IR testing rather than continuity testing. I know this may appear pedantic but I'd rather be a live pedant than an electrocuted whatever-a-smoking-corpse-that-when-alive-was-not-a-pedant-is-called.

Its a frigging continnuuity test bud... When is your homework due in bud?

 

[Rampantchilli]

You could just do the work at night, that way you will be sure the supply is on, so when you isolate you can carry out your 'normal' safe isolation and get the correct results.

btw, E7 is on for 7hours overnight, e10 doesn't exist, it commonly know as d rate or d10 and depending on which company put it in historically, it usually still does 7 hours over night, and the other 3 hours are afternoon boost, there's also a 12 hour rate version available, with 3 'off peak' periods, but that will just blow your mind if your scared of e7 lol

 

[NickD]

1. Anyone who thinks this is about how to use a voltage indicator has completely missed the point and not understood the problem.
2. Anyone who thinks they know what they're doing by doing standard unaugmented safe isolation, on a board with a dead supply that may become live, needs to review their practice.
3. Continuity test proves the main switch is open and will withstand (typically) 24V. Repeat, 24V. Check your meter's low ohms range spec if you don't believe me. Air gaps do not obey Ohm's Law. Why bet your life on the hope that it will do the same at the peak voltage of 230V ac rms, when you could be sure by IR testing it which takes the same time? What you want to be sure of is that you are insulated from the supply. Big clue there.

 

[Joe_b87]

Proving dead & safe iso on Economy 7

Strap a volt stick to the incoming, were washing up gloves and thick socks!! ;-p

 

[Knobhead]

I suppose risking blowing the cutout fuse is better than risking blowing your mind.

Better than reading this litany of misinformation. You could die of boredom!

 

[Guest55]

1. Anyone who thinks this is about how to use a voltage indicator has completely missed the point and not understood the problem.
2. Anyone who thinks they know what they're doing by doing standard unaugmented safe isolation, on a board with a dead supply that may become live, needs to review their practice.
3. Continuity test proves the main switch is open and will withstand (typically) 24V. Repeat, 24V. Check your meter's low ohms range spec if you don't believe me. Air gaps do not obey Ohm's Law. Why bet your life on the hope that it will do the same at the peak voltage of 230V ac rms, when you could be sure by IR testing it which takes the same time? What you want to be sure of is that you are insulated from the supply. Big clue there.

still going after 3-4 pages.......

 

[Guest55]

right ! thats it !!
time to bring this drivel to an end

if you not happy by just switching off.............


then pull the freaking fuse out !!!!!!!!!!!!!!

ok ?
;-)

 

[Tuttle]

3. Continuity test proves the main switch is open and will withstand (typically) 24V. Repeat, 24V. Check your meter's low ohms range spec if you don't believe me. Air gaps do not obey Ohm's Law. Why bet your life on the hope that it will do the same at the peak voltage of 230V ac rms, when you could be sure by IR testing it which takes the same time? What you want to be sure of is that you are insulated from the supply. Big clue there.

What is the chance of a switch looking open circuit at 24V but then passing 230V? Very, very small I should think, especially if it doesn't appear to be damaged in any way.

 

[Tuttle]

right ! thats it !!
time to bring this drivel to an end

if you not happy by just switching off.............


then pull the freaking fuse out !!!!!!!!!!!!!!

ok ?
;-)

But how can you be sure you've pulled the correct fuse if it's already dead!? :sifone:

(only joking BTW)

 

[Guest55]

But how can you be sure you've pulled the correct fuse if it's already dead!? :sifone:

(only joking BTW)

pull all of them !
;-)

 

[Tuttle]

There's some funny threads going on here at the moment, I really feel like I must have been smoking something today :21:

 

[snowhead]

pull all of them !
;-)

But what if you've missed one...

You know you've pulled the ones you can see, but how do you know there aren't any hidden ones???????