Shouldn't be getting 1000 mega ohm reading between neutral and earth as they share the same fault path back to the meter and on to the star point of the transformer the neutralising link coming into the board needs to be disconnected for this to work
Hi great video. 1 question please, ...so do you actually go around the plant, factory, house, building etc. and disconnect all PC's, toasters, equipment, light bulbs, and burglar alarms. surely youl miss something, and then run the risk of blowing up something, pls could you explain how you go about that task.
Fredre Olivier... good point just imagine 1 month of second fix and you now got to take apart 1 months worth of 2nd fix to test so you can hand in the results before hand over on Friday. Now what do you do?😦😢
Fredre Olivier Just disconnect the circuits with sensitive equipment and do a test between live and neutral connected together to earth and that stops any damage, i'm no expert but this is what i've read in gn3
Hi. Should you have not removed the neutral conductor before carrying out a 'global' insulation test as it would be connected to earth upstream? The isolator is 3 pole only and does not break the neutral
@@Bacon89100 Neutral is connected to earth at the transformer so it wouldn't matter. If it is a 3 pole isolator then the neutral is not being disconnected at the DB
Read your BS7671 part 6. This is a common misconception. If you test 600V cables at 1000V you have exceeded their Vmax and so are theoretically kippered.
Why did Chris set the insulation tester to 500v when you should test the circuits at double the voltage. I assume that a 3 phase DB is 430v, shouldn't the megger tester be set at 1000v. Can anyone explain?
Have to disagree with you, sorry! The breakers are square D and are in fact in the on position, just as you correctly said they should be for this test. Thanks for trying to be helpfull though.
You should NEVER test between ACTIVE and NEUTRAL!! Only between ACTIVE (or phase) and EARTH or NEUTRAL and EARTH. If you put 500v across a single phase load you’ve got a very high chance of fucking something
Brilliant i passed a recent test because of this video very well explained...
Great job I am following your video , It's really interesting & helpful
Shouldn't be getting 1000 mega ohm reading between neutral and earth as they share the same fault path back to the meter and on to the star point of the transformer the neutralising link coming into the board needs to be disconnected for this to work
do you have to disconnect rcbo and ring circuits and if so how do you get IR values for them separately
Hi great video. 1 question please, ...so do you actually go around the plant, factory, house, building etc. and disconnect all PC's, toasters, equipment, light bulbs, and burglar alarms. surely youl miss something, and then run the risk of blowing up something, pls could you explain how you go about that task.
Fredre Olivier... good point just imagine 1 month of second fix and you now got to take apart 1 months worth of 2nd fix to test so you can hand in the results before hand over on Friday.
Now what do you do?😦😢
Fredre Olivier Just disconnect the circuits with sensitive equipment and do a test between live and neutral connected together to earth and that stops any damage, i'm no expert but this is what i've read in gn3
How do you go about the task? Easy.
If it's a Friday afternoon, you just put it on 250v instead of 500v.
i would drop voltage to 250v d.c and/or put live conductors together (as one) and test them between earth
Great video, where did you get button-type probes from ?
RCCB and MCB Continuit test and installation test (do i need to keep the MCB and RCCB in ON position)
if i have a Dol on an isolator can i still test 500v with the isolator in the off position right?
Good.vidio
what about c.t coils around feeds ect. ?
Hi. Should you have not removed the neutral conductor before carrying out a 'global' insulation test as it would be connected to earth upstream? The isolator is 3 pole only and does not break the neutral
I guess it depends on the earthing arrangement.
He's correct if it's TN-S. You're 100% right otherwise, though.
@@Bacon89100 Neutral is connected to earth at the transformer so it wouldn't matter. If it is a 3 pole isolator then the neutral is not being disconnected at the DB
What is over range?
Should be 1000v insulation test between phases as it needs to be double the voltage , 500v is only 100v over normal voltage
Read your BS7671 part 6. This is a common misconception. If you test 600V cables at 1000V you have exceeded their Vmax and so are theoretically kippered.
Incorrect. Test is 500v for systems up to and including 500v.
@daniel bryan, I'm confused, please could you explain why you think that?
If one particular circuit breaker is needed to be tested, where shall the test be carried out, upstream or downstream of the breaker?
thank you v much sir
Rest of his videos are good
Why did Chris set the insulation tester to 500v when you should test the circuits at double the voltage. I assume that a 3 phase DB is 430v, shouldn't the megger tester be set at 1000v. Can anyone explain?
BS7671 states this is the voltage to use ‘up to and including 500V with the exception of SELV and PELV, but including FELV'
Thank you very much
👍👍
I like is megger
Have to disagree with you, sorry! The breakers are square D and are in fact in the on position, just as you correctly said they should be for this test. Thanks for trying to be helpfull though.
j'aime pas le triphase
Jane South I like it though 😂
You should NEVER test between ACTIVE and NEUTRAL!! Only between ACTIVE (or phase) and EARTH or NEUTRAL and EARTH. If you put 500v across a single phase load you’ve got a very high chance of fucking something