International Gas Detectors TOC-635, Руководство по установке

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External 24V DC
PSU
L N E 0V 24V
Ensure PSU is dedicated to the gas detection system and
that earth and 0V is linked at the PSU. Ensure segregation
between mains and DC cabling to BS 7671. A suitable
PSU is available from IGD PN 5921101
635 Gateway version shown
Distance Should be
as short as possible.
Under 300mm. Use
Cable Provided Note
Position of Filter
The PSU supplied by IGD comes with a power cable for the hub
card and an earth line choke. The earth line choke is provided to
attenuated electrical noise sometimes seen on earth systems in
electrically ‘noisy’ industrial environments. Failure to fit this correctly
may result in operational problems. Note the indicated incoming
Earth position ‘E’
Note the link between the PSU earth and PSU 0V
connections.
Signal cables connected to the hub cards
MUST be screened using the cable types
indicated. The screening must be
continuos as close as possible to the hub
card connection point leaving no more
than 75mm of unscreened cable.
Cable screens need to be taken to earth
points minimising the cable distance and
using either the cable screen itself or a
minimum 1.5mmSQ cable. Cable tails
should not be longer than 100mm
Gateway Product Versions, General Requirements
Earth Line Choke to
PSU.
Power to the PSU
must be from
unswitched fused
spur fused at 3A
with double pole
circuit disconnect.
E