94
for
cleaning, shall
be
fitted
between
the
motor
nozzle
and
the
alarm
valve
connection.
The
water
outlet
shall
be
arranged
so
that
any
flow
of
water
can
be
seen.
14.1.3 Piping to water motor
The
piping
shall
be
galvanised
steel.
The
equivalent
length
of
pipe
between
the
alarm
valve
and
the
water motor
shall
be
not
more
than
25m
assuming
an
equivalent
length
of
2m
for
each
change
of
direction.
The
pipe
shall
be
fitted
with
a
stop
valve
located
within
the
premises
and
shall
be
provided
with
a
permanent drain
through
an
orifice
of
not
more
than
3mm
in
diameter.
The
orifice
plate
may
be
integral
with
the
pipe fitting,
and
shall
be
made
either
of
stainless
steel
or
of
a
non-ferrous
material.
14.2 Electrical water flow and water and air pressure switches
14.2.1 General
Electrical
devices
to
detect
the
operation
of
sprinkler
systems
shall
be
either
water
flow
switches
or
pressure switches.
14.2.2 Water flow alarm switches
Water
flow
alarm
switches
shall
only
be
used
in
wet
installations.
A
test
connection
shall
be
fitted downstream
of
each
switch
to
simulate
the
operation
of
a
single
sprinkler.
It
shall
be
fitted
with
a
drain.
The draw-off
pipe
shall
be
galvanised
steel
or
copper.
The
pressure/flow
characteristic
of
the
fully
opened
test
valve
and
draw-off
pipe
shall
be
equal
to
that
of
the smallest
nominal
bore
sprinkler
supplied
through
the
flow
switch.
Any
orifice
plate
shall
be
at
the
pipe
outlet and
shall
be
either
stainless
steel
or
non-ferrous
material.
The
test
pipe
outlet
shall
be
positioned
relative
to
the
drainage
system
in
such
a
way
that
the
flow
of
water can
be
seen
during
tests.
14.2.3 Dry and Pre-action systems
Each
discrete
section
of
the
installation
pipework
should
be
provided
with
a
low
air/gas
pressure
alarm,
to provide
a
visual
and
audible
warning
in
an
area
with
responsible
manning.
14.3 Transmission of alarm signals to a permanently manned location
Any
automatic
sprinkler
electrical
alarm
connected
to
a
permanently
manned
location
shall
conform
to
EN
54-2
"Control
and
Indicating
Equipment".
14.4 Monitoring stop valve
The
monitoring
signal
shall
be
transmitted
to
a
permanently
manned
location.
15.1 General
15.1.1 Underground piping
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