WIKA FLM - Handbuch (Seite 14)

GB
14 WIKA operating instructions level sensor model FFG
13445627.01 12/2010 GB/D/F
If a supplier provides, for example, 13 V at 21.5 mA, the sum
of resistors contained in the supply line is not allowed to be
in excess of (13 V – 10 V) / 0.0215 A = 139 Ω. If the cable is
of a cross-section of 0.5 mm² and if no burden is contained
in the line, the feeder line is not allowed to have a length
greater than L = 139 (Ω) x 0.5 (mm²)/0.034 m = 2050 m.
Note the given connecting pattern
The connection should be carried out with light-blue-marked cable. The
diameter of the connecting cable must be within the clamping range
of the cable gland (5-10 mm). Using other cable diameters involves the
danger of moisture ingress.
The use of individual strands is not permitted!
Cable capacity and inductivity
When determining the required cable length, the highest
permitted inductivities and capacities of the connected
intrinsically safe control unit should be observed. These
values are not allowed to be exceeded.
Connecting the cable
Wiring must be in a voltage-free condition. Compliance
with all special VDE regulations and local provisions of
installation is imperative.
■ Unscrew lid (1) of probe head with open-end wrench
■ Loosen sleeve nut (2) of cable bolting
■ Insert dual-core cable(4) through sleeve nut and re-tighten the same
■ Connect dual-core cable (4) to screw terminals in probe head,
marked by (+) and (-)
■ Re-screw lid (1) on probe head
5. Electrical connection