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The likelihood of a typo increases by the square of the number of readers.

I understand the reason for the rule. It's the interpretations that are interesting. The phrase "as close as practicable" has distances and wiring methods attached. It's almost like we still have amendments.

I would say that rule is made considering voltage drop. So "as close as posible" does not seem defined completly. Voltaage drop can't be more that 5%.
From service to main panel 2%.
From main panel to branch 3%.


Now I am still an apprentice so I might be wrong, that is why I like to ask questions. Forgive me if I am anoying.

B.C. Directives say that any distance greater than 1.5m is considered unacceptable without prior consultation with Authority.
"To limit the risk of fire, because service conductors lack effective overcurrent protection."

Ummmmmmmm....

I'm wondering why that should be up to us to 'solve'. Afterall aren't conductors supposed to have effective overcurrent protection?

Put overcurrent protection in the meters is an idea. Then we can run them wires as far as practicable
Thanks Hydro! (I'll take one of those electric crimpers too)

The issue is unrelated to VD in this case. The conductors ahead of the main switch are considered to have no overcurrent protection. You probably have seen fuses on the pole top transformer that supplies the 6 to 10 houses you are all connected to. If one of the ungrounded (hot) wire faults to ground in a service raceway the utility transformer might see that bug bump in current as a load rather than a fault. I have certainly seen a few service panels and raceways burned completely away before the fuse on the transformer or a connection in the meter or triplex opens under the heavy current flow. If this service pipe was inside your walls it might set the house on fire before the fuse on the transformer blows. It is very common for utility transformers loaded to %200 of their rating when connected to residential services. In the case of the panels I have seen burned away I got to the house after the fire trucks.
By encasing the raceway in concrete it is hoped that the concrete will enclose the melting raceway and protect the combustible wall it is inside. Eventually the fuse will open or the raceway will burn away enough to stop conducting fault current.
Then there is the problem of theft from the utility. We have seen more than a few raceways cut open ahead of the meter to tap the utility wires. Pot growers seem to love to do this.

Okay... but I won't forgive you for saying THAT!

Dude. Some of us don't look down on 'apprentices' (people). Talk to us, not the ones that do.

If you have a situation where "as close as practicable" is not a good location for your panel, you could consider a fusible disconnect after the meter, then place your loadcenter where ever you need at whatever distance.

This is particularly suitable when the meter is mounted on a garage, so the disconnect can go inside the garage, or where there is room for a fusible disconnect inside the house but not a combination panel.

.

I did service entrance 400A, 200A, and 100A. I do remember
connecting meter box. It is logic to fuse meter, but I never saw one (not plugged in).
So we need a disconect switch to be as close as posible.

I will quote both USA and France side with the max distance from meter to main panel the USA side it will varies a bit depending on which states they use that codes but most of them say short as possible so tyically less than 2 meters from the main meter but few do can go much as 4 or 5 the most.

In France we are limited to 3.5 max distance but most case they are useally on outdoor main disconnect switch.

Merci.
Marc