[top-posting removed for ease of reading]

In message ,
"LOZ34" wrote:


"BigWallop" wrote in message
...

"LOZ34" wrote in message
t...
According to my on site guide, Zone 1 SELV allowed, Water heaters,
showers,
shower pumps allowed. other fixed equipment that can not reasonably be
located elsewhere allowed if protected by a 30mA RCD.

loz34


SELV stands for "Safe Extra Low Voltage" LOZ34, so anything that runs on a
SELV system
is more than likely running through an isolated step down transformer to
give the low
voltage and ampage needed to be within "Zone 1" of a wet room area. The
point of the
SELV rating is to allow electronic equipment to be in an area where it
might be
directly splashed or come into contact with high amounts of water or
steam. I don't
fancy splashing water on a mains powered item while I'm standing in the
bath. :-))




the point I was making is that it is NOT a requirement for showers and
equipment designed to be in zone 1 to be protected by an RCD.

Loz


Sneaky, but well spotted; it's there in the wording. You are absolutely
right, neither the OSG nor BS7671 make it mandatory for either a water
heater or a shower pump to be RCD protected if they are designed for use
in zone 1.

I suspect that this common belief is another case of John Whitfield-ism:

(The Electrician's Guide to the 16th Edition etc... Revised 6th edition,
page 134)

"Water heaters and shower pumps may be installed in Zones 1 and 2, as
may other equipments suitable for the conditions, provided that they
have the required protection against water and are protected by an RCD
with a rating of not more than 30mA."

Note how the use of the comma-separated phrase "as may..." makes it a
requirement that everything must be RCD protected. In BS7671 and the OSG
this information is set out as a numbered or tabulated list and it is
obvious that the RCD requirement only applies to one item on that list.
I suspect therefore that Whitfield's assertion that an RCD is required
is due mainly to dodgy grammar.

On the other hand, there's no harm in RCD-ing the shower either...

Hwyl!

M.

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