Reed -CONTROL RCS Betriebsanleitung Seite 11

1 Hazard warning
The operating temperature and the operating pressure must never exceed the values specified on
the type plate or in the data sheet. The maximum operating pressure is dependent on the equipment.
The equipment must not be used as a safety-relevant limiting device or control unit within the
pressure range.
Sensors may only be operated with low voltage. An overloading of the equipment may result in
its destruction. The maximum values specified on the type plate or in the data sheet must not be
exceeded.
The equipment must not be exposed to heavy mechanical loads, vibrations or impacts during storage
and operation. It must not be used as lifting equipment, a footboard or a transport device. The
equipment must be protected against magnetic fields.
It is forbidden to make any changes to the equipment, e.g. shortening the sliding tube. This would result
in the destruction of the equipment.
In the case of explosion-proof equipment with a connection cable, the cable must not be shortened
without guaranteeing that an earth conductor is prepared with the cable's protective sheath. The ATEX
supplementary sheet must be adhered to.
If the equipment is fitted to the connection cable freely suspended above the medium, a steel cable
must be mounted to the plug as a strain relief measure by means of a steel bracket. The bracket and
steel cable must be purchased from Reed Electronics AG.
Fire protection equipment must be attached to the side of the system. Damage to the equipment by
external fire makes it impossible to monitor and control the system.
Installation in ferromagnetic connecting pieces will impair the functionality of the equipment.
In gas group IIC areas, the junction box must not be electrostatically charged. It must not be wiped dry.
If the aluminium junction box is struck, ignitable sparks may be formed. This must be taken into conside-
ration if the junction box is installed in zone 0.
Important: Non-adherence to the hazard warnings set out above may result in the equipment beco-
ming damaged and thus lead to the malfunction of downstream control systems, and to personal injury
and material damage! The manufacturer shall not be held liable for any damage caused by misuse or
incorrect operation.
2 Functionality
2.1 RCS float switch (incl. EX and EXNP designs)
Due to the magnetic field generated by the magnet inside the float chamber, the reed contacts (pro-
tective gas contacts) arranged in the sliding tube are actuated according to the fill level required. De-
pending on the contact type (normally open or normally closed), this opens or closes the control circuit
and transmits a switching command that is used for controlling or signalling. If the equipment is fitted
out with a temperature switch, the same function is triggered by the switch upon reaching the defined
temperature.
2.2 RCK and RCK2 sensors (incl. EX and EXNP designs)
Sensors function according to the float principle with magnetic transmission. The sliding tube contains
a chain with reed contacts and resistors in a potentiometer circuit. The reed contacts are actuated by
the magnetic field generated by a magnet inside the float chamber. The level of the float is changed
with the level of the medium that is being monitored. The closing reed contact taps the point of the
resistor chain. The resistor chain is not interrupted. The exact level can now be determined based on
the resistance value. The resistance value can be converted into an analogue signal, e.g. 4 to 20 mA,
using a control device.
3