IGD 2-Wire Systems, Installer'S Manual

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16
Cable Type Guidance
L1
L1
L2
L2
Cable Screens direct to
commoning blocks provided
CY Style Cable
Recommended Cable Preparation
FP Style Cable (Preferred Option)
SWA Style Cable
CY Type cable has a braided screen which should be trimmed
back to ensure no trimmed conductor ends up on sensitive
PCB components, tracks or terminals where it may short. The
screens of the incoming cables should be terminated to the
floating terminal block provided to ensure screen continuity.
Trim back any unused conductors and ensure the braid is
insulated with heat shrink or insulation tape and/or sleeve.
Unused
L1
L2
Unused
L1
L2
Drain Wire Screen
FP style cable is fitted with a foil screen and drain wire. Generally this is easier to terminate than
CY type cable. Trim back any unused cores and foil screen. Ensure the drain wire is insulated
with suitable size sleeving and terminates to the cable screen terminal
SWA style cables are usually only recommended for used with ATEX EXD housings where the
universal cable glands ground the cable armour to the housing. This provides both an effective
EMC screen and mechanical protection. Ensure unused conductors are trimmed back and
isolated. If terminating to plastic enclosures fit ‘pan handles’ and terminate on the outside of the
enclosure to ensure screen continuity
IGD’s 2-Wire gas detection systems operate using screened cabling of appropriate cross sectional
area. There are no specific requirements and our typical advised cable types are indicated below.
Cable screens, either foil and drain wire, braid or armouring must be continuous between devices and
grounded for effective operation. Ancillary devices such as stop buttons, beacons, sounders etc should
commoned to the earth blocks provided as indicated below.
Strip Conductors 7mm Ensure No Stray
Strands