Model 4802A
12
3.7 Installation Instructions for the Sensor
The interconnecting cable should have an overall screen or screen and armour. Cables
to BS5308 or equivalent are suitable. Note that the terms “screen” and “shield” are
equivalent for the purposes of this manual.
Interconnecting cables should be segregated from power and other “noisy cables. Avoid
proximity to cables associated with radio transmitters, welders, switch mode power
supplies, inverters, battery chargers, ignition systems, generators, switchgear, arc lights
and other high frequency or high power switching process equipment.
In general, maintain a separation of at least 1m between instrument and other cables.
Greater separations are required where long parallel cable runs are unavoidable. Avoid
running instrument cable trenches close to lightning conductor earth pits.
General Monitors do not recommend the use of cable shoes or crimps on any junction
box or housing wiring terminals. Poor crimping can cause bad connection when unit
experiences temperature variations. We therefore recommend good practice is to just
terminate cable or sensor wires as is, especially in remote sensor applications.
Complete all cable insulation testing
before
connecting the cable at either end.
Gas Sensor &
Nut
Drain Wire
Isolated here
Continuity Plate
Screened and
Armoured Cable
Cable Glands
Gland Nuts
Ferrite Sleeves
Ensure that approved Ex”e” cable glands are used in the junction box and that these are
correctly installed according to the manufacturer’s instructions. The cable glands must
be electrically connected to the continuity plates by means of suitable nuts. The cable
armour must be terminated in the glands so as to ensure positive electrical connections.
A ferrite sleeve (P/N 363-005) must be placed over all cores and the screen drain wire
immediately adjacent to the junction box, as shown in the above illustration.
Connect the corresponding conductors of the interconnecting cable to the appropriate
terminals in the function box.
