Control nigh rate main high risk

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Dan L
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Control nigh rate main high risk

Post by Dan L »

Is a control nigh rate main high risk?

ESR say

"mains means those fittings forming part of an installation that are used for the
supply of electricity to the MEN switchboard of the installation that is closest
to the point of supply"

Just to be sure this night rate main is connected from night rate meter to double pole main switch.

I feel like it is not just because I think the night main is more re directing electricity that is being supplied from the a actual mains and if a night rate main is added it does not alter any of the settings at the time of inspection.

If you removed the main phase the night rate main would not be supplying electricity.

But if be interested to hear what yiu guys think as I'm often wrong.
AlecK
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Re: Control nigh rate main high risk

Post by AlecK »

Yes it's mains.
It fully meets that definition.
And because it's "mains' installing it is high risk PEW.
Which then is required to be Inspected under ESR 70.

Basically mains start at Point of supply and end at (for actives) the line terminals of main switch(es) and (for neutral) the main N-bar.
The mains active is split in the metering enclosure, the mains from that point becomes a 'common neutral' circuit ; and 2.2.1.2 applies.
So when adding a controlled or different-tariff active; there's a definite change to the configuration that brings in different requirements
and that justifies an Inspection.

Note that because it's "mains" and not a final subcircuit; item (b) doesn't apply - so the main switch is not actually required to be a single device.
Which helps when you get past 3 mains actives (eg 3-phase general plus 1 or 2 controlled).

Similarly (d) doesn't generally apply to mains.
Dan L
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Re: Control nigh rate main high risk

Post by Dan L »

Seems I'm wrong again but good to be learning. Thanks
JamieP
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Re: Control nigh rate main high risk

Post by JamieP »

Good question, interesting read
AlecK
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Re: Control nigh rate main high risk

Post by AlecK »

It can't be wrong to ask a question; as long as you've had a look at the rule (or at least tried to find it).
Discussion of interpretations is always good
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