Separate ground for *each* circuit?

DaveC wrote in news: snipped-for-privacy@news.individual.net:

you dont *need* to run grounds for all 4, but, if weighted correctly, your car doesn't *need* 4 wheels. it is imperative to run them for at least 2 reasons: 1, its a code violation not to (at least in the US). 2: if anything ever shorts out or something like that, its always nice to know that things are properly grounded and wont be transferring the load of power from the short and whatever else is in-line with that one ground.

people generally rub 3 conductor romex type wire (as i think is actually a code requirement) from the breaker panels for "normal" household watages. which includes 2 grounds and a hot. anyway, as it is a safety issue, i would run the grounds.

-Sam

In the UK you would run a single cable containing two cores and an earth wire in a ring out and back to the board. You get an earth "free" for each ring/circuit.

to

The UK is unusual in having fused plugs as standard. 13A max in each plug, and 30A at the panel for each ring. They're also allowed to spur one outlet off each ring outlet. That's why the proposed 16A euro standard died, the Brits would need fused outlets and didn't want it.

Ring circuits are not used much elsewhere in the world. They're actually illegal in some places.

If you're trying to reduce the number/size of cables you're running from the breaker panel to the new construction, another way is to put in a sub-panel somewhere in the new construction. Then you'd run a single set of wires (hot + neutral + ground) from your existing box to the new one, and the new box would contain six circuit breakers, one for each circuit it's supplying.

There are a bunch of regulations having to do with sub-panels, but if the new construction is far away from the existing breaker box, it might be worth jumping through the regulatory hoops to put in a subpanel.

If running conduit and building wire then only one ground is requires for the entire conduit regardless of the number of circuits. Ground must be sized for the largest circuit in the conduit. 20 amp/12 ga. wire would need one #12 ground. If you are running any type of cable - NMB, MC, AC - then each would contain it's own ground. Bathrooms are now required to have dedicated circuits similar to small appliance branch circuits in kitchens. Sorry I can't give exact details as my code book is not available and I don't do residential.

We need more details. Your location will change what rules apply. Is this residentail or commercial. Four baths makes me think commercial which requires a licenced electricial in most places. Are we talking romex or conduit?

-Chris