Page
11
©
2008
Gastech
Australia
Pty
Ltd
2.3.2
Connection
to
Barriers
Intrinsic
safety
barriers
are
devices
that
limit
the
current,
voltage,
and
total
energy
delivered
to
a
sensor
in
a
hazardous
area
or
flammable
environment
in
order
to
prevent
an
explosion.
The
barriers
designed
to
protect
the
system
must
be
mounted
outside
of
the
hazardous
area
in
an
area
designated
as
Non
‐
hazardous
or
safe
in
which
the
hazard
is
not
and
will
not
be
present.
If
you
are
utilizing
the
D
‐
Guard
TM
in
a
Hazardous
environment,
you
will
need
to
select
an
appropriate
IS
barrier.
Selection
of
the
type
of
barrier
requires
consideration
of
the
voltage
drops
that
occur
in
the
system.
As
the
D
‐
Guard
requires
a
minimum
of
12VDC
to
operate,
the
voltage
drops
in
the
barrier
system,
controller
load
resistor
and
cabling
cannot
exceed
the
power
supply
voltage
less
12VDC.
WARNING:
Installers
should
consult
the
Intrinsically
Safe
Barrier
manufacture
and
refer
to
IEC
Intrinsically
Safe
System
Standard
IEC
60079
‐
25:2003
or
AS/NZS
60079.25:2004
before
selecting
a
suitable
barrier.
A
D
‐
Guard
operated
without
a
barrier
will
require
the
D
‐
Guard
to
be
inspected
by
the
manufacture
to
confirm
that
none
of
the
safety
components
have
been
damaged.
Summary of Contents for D-Guard
Page 2: ......
