A hotel requires 36 rooms to be connectd with a seperate isolator in each room for that room.
For each room the requirement is sockets (Say 16A radial) and lights (say 6A circuit with calculated load of 1.25A)
The alternative designs are:
Belt and Braces
20A Sub main to each room. in which case (from voltage drop limitations)
4mm gives max run of 30m
6mm gives max run of 44m
10mm gives max run of 72m
or
Minimum Cost
applying diversity in which 2 room may be assumed to be running at half maximum demand and 4 rooms at minimum demand giving a demand of 26A
30A sub main daisy chained to 6 rooms, with cable of:
4mm gives max run of 20m
6mm gives max run of 30m
10mm gives max run of 47m
Is the Minimum Cost approach allowable, and if not which regulations prohibit it?
For each room the requirement is sockets (Say 16A radial) and lights (say 6A circuit with calculated load of 1.25A)
The alternative designs are:
Belt and Braces
20A Sub main to each room. in which case (from voltage drop limitations)
4mm gives max run of 30m
6mm gives max run of 44m
10mm gives max run of 72m
or
Minimum Cost
applying diversity in which 2 room may be assumed to be running at half maximum demand and 4 rooms at minimum demand giving a demand of 26A
30A sub main daisy chained to 6 rooms, with cable of:
4mm gives max run of 20m
6mm gives max run of 30m
10mm gives max run of 47m
Is the Minimum Cost approach allowable, and if not which regulations prohibit it?
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