| ak_47_boy |
| When using isolated ground receptacles where should each ground go? Should all the grounds be stared at a water pipe? |
|
|
| Gold_xyz |
see also :
http://en.wikipedia.org/wiki/Ground_%28power%29
It has need to verify if water pipe can be used for ground... :att'n:
In some cases the system can be isolated from earth or have insufficient conductivity.
In this way instead of discharge toward earth all taps are electrified :D
In the last years in my country the company of water has replaced
all metal pipes with plastic pipes... :cannotbe:
bye |
|
|
| TomWaits |
Duplex receptacles with isolated grounds are supplied with direct connections to the distribution panel. At no point should the ground wire connect to other metal objects in the building or other circuits.
This is very simple in Canadian residential applications using NMD90 wire (typical) traveling through wood members. Simply run a direct feed from your breaker panel to the outlet.
It gets more complicated in commercial applications using steel stud walls and metal conduit race ways. Though it is very basic if you understand the concept.
Your distribution panel "should" have a ground connection to the water main where it enters the building. Grounding your circuit to the ground in the panel should be fine. I have, in a few cases, run a new separate ground to the water supply of a building but in all of these cases it was due to the fact that the distribution equipment was using the metal supply conduit for ground connection.
Cheers,
Shawn. |
|
|
| AndrewT |
Hi,
here in the UK, we are not allowed to use other metal services to improve or provide a safety earth.
We do however have very strict rules on earth bonding all metal services around the house. The purpose of this is to prevent electocution if a user were to inadvertently touch a live service due to a wiring fault elsewhere, even outside the property.
We even have to earth bond across the heating radiator pipes, in case the user removes the radiator (for decorating or repair) and touches the two open ends. |
|
|
| TomWaits |
| quote: | Originally posted by AndrewT
Hi,
here in the UK, we are not allowed to use other metal services to improve or provide a safety earth. |
Same here "but" when using armoured(BX) cable and metal conduit often these can travel near or against metal ducting, steel studs, metal drop ceilings, plumbing etc. These unwanted connections are not regulated and occur very often. An isolated ground ensures a decent connection to earth without the unwanted contact to other metalic components. In a residential application the situation is much more simple if it is a wood structure and the electrical cable is non metalic ie NMD (Non Metalic, Dry location).
Cheers,
Shawn. |
|
|
|
