hi all,

is there any case where shorting the neutral with earth and then using the supply (line, neutral earth) can have adverse effects?

 

of course there is system like that. this is according to the earthing system. in TNC system only three phase and forth wire is (neutral + earth).

 

Yes. If you intertie the ground[ing] and neutral (groundED) conductors downstream of the point of distribution, and both the ground and neutral become severed between the point of distribution and point of use, and there are loads connected across line and neutral, supposedly grounded elements will assume line potential. Don't do it.

 

Well, the earth and neutral are usually "shorted" together at some point, mostly at the service point.

If you are refering to adding an additional neutral to earth bond at some point downstream chances are it won't hurt anything. It is a bad idea but it is commonly done by people who do not know any better.

It will mess with ground fault detectors among other things.

In normal operation it probably won't "hurt" anything, although current will flow continuously on the ground wire, and that is usually considered undesirable.

having said that, utilities routinely do this on the primary side. they earth the neutral many times, sometimes on every pole, sometimes every other pole.

--
Bob

 

hi steve,

do you mean at that point line and neutral get interchanged? ok, if i make sure that line connects to line and neutral connects to neutral, then is there still a problem?

pardon me, if i missed it completely!