On 13/11/2017 17:04, whisky-dave wrote:
On Monday, 13 November 2017 16:37:27 UTC, John Rumm wrote:
On 13/11/2017 13:10, whisky-dave wrote:
On Saturday, 11 November 2017 15:10:34 UTC, ARW wrote:

Voltage 202


The fact that the voltage drops to 202V suggests that the wiring is
a little bit suspect.

How ? Surely it's just basic ohms law,

It is... and one should design circuits such that at full load they
still meet the basic requirement of showing no more than 4% or 5%[1]
voltage drop.

So what should be the full load on a 32 amp MCB ?

The maximum design load would be 32A. With that load, you should drop no
more than 5% for socket circuits. If you overload the circuit, then its
not unreasonable to be out of spec for voltage drop.

Since it does not appear that yours are meeting that requirement,

how do you work that out ?

You said the voltage was 202V. If your starting point was 220V then that
is well out of spec (given your actual applied load would probably be
close to the 32A design load even with 5 heaters running, since the
actual power dissipated by each heater at that voltage would be well
under the nominal 2kW)

it
would suggest that either the cable run in the circuit itself or that of
the sub main feeding the CU at the origin of the circuit is
underspecified for the length of cable in use.

This isn't a home CU unit.

Doesn't matter...



--
Cheers,

John.

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