Reed -CONTROL RCS Betriebsanleitung Seite 12

3 Area of operation
Float switches and sensors must only be used to control and monitor the fill levels of liquid media.
The liquids must not contain any severe contaminants or coarse particles and must not be prone to
crystallisation. Please make sure that the equipment materials (sliding tube, float, etc.) that come into
contact with the media have a sufficient level of chemical resistance to the media to be monitored.
4 EX zone area of application
(explicitly concerns all EX and EXNP designs)
Only equipment that is explicitly identified as EX equipment can be used in EX zones. Explosion-
proof float switches are suitable for use in areas in zone 0 that are at risk of gas explosions. The
maximum operating temperature and the EX designation on the type plate as well as in the ATEX
supplementary sheet must be observed. Explosion-proof float switches are only permitted to be con-
nected to a certified and intrinsically safe supply current and evaluation circuit with the maximum
values in accordance with the manufacturer's declaration in the supplementary sheet. The operating
temperature ranges can be found in the temperature class table and the equipment specifications
on the type plate.
5 Assembly and installation
The dimensions of the threaded socket must be identical to the dimensions of the equipment's threaded
plug. In designs with flanges, the nuts and bolts appropriate for the flange must be used. A suitable gasket
(not supplied by Reed) must be provided for sealing. Please make sure that it is installed in the correct
position. The maximum deviation from the verticals is ±30°. Where installation openings are smaller than
the diameter of the float, the float must be disassembled before the switch is installed. The position of the
float limit (adjusting ring) must be marked prior to disassembly. In the case of explo sion-proof float switches,
the PTFE washer must be installed back on the adjusting ring. If the floats are not labelled, the installation
position must be labelled accordingly (e.g. «top»). Once the float switch has been installed, the float
must be positioned back inside the tank (observe the installation position!). The float limits must then be
reattached at the marked positions. The number of floats and the number of float limits are dependent on
the number of switch points. In the case of the flexible float switch, the minimum bending radius is 85 mm.
6 Electrical connection
The electrical connection must be executed in accordance with the regulations applicable in the
destination country and may only be carried out by specialists with the relevant qualifications. The
electrical connection is carried out in accordance with the type plate attached to the power outlet or
cable. In the case of equipment with a power outlet, the cable is fed through the cable fitting and sealed,
and the outlet is sealed again tightly with the cover.
7 Electrical connection in an EX zone
7.1 Only EX equipment and EX equipment with earthing flexes
Please proceed as described in Section 6 «Electrical connection» and Section 4 «EX zone area of
application». Please also observe that the earthing terminal in the power outlet, or the earthing flexes
in the connection cable, must be connected to the equipotential bonding to prevent the electrostatic
overloading of the metal parts. The ATEX supplementary sheet must be observed.
7.2 Only EXNP and EC equipment without earthing flexes
Please proceed as described in Section 6 «Electrical connection» and Section 4 «EX zone area of appli-
cation». Please also observe that the float switch housing must have a live connection to the equipoten-
4