Buhler GAS 222.21 Ex2, Installation And Operation Instructions Manual

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GAS 222.21 Ex2
4.9.3 Connecting the Temperature Switch
According to IEC/EN 60079-11 the temperature switch in this probe is a simple electrical equipment and to be considered a
purely ohmic circuit. It may only be operated with a type-tested controller with an intrinsically-safe circuit.
Temperature switch connection data:
U
i
= 30 V; I
i
= 100 mA; C
i
= 0; L
i
= 0
Never exceed the connection data!
4.9.4 Connecting the Earth Conductor/Earthing
Always connect all of the designated connections on your unit to your protective conductor system. Connect the earth to the ad-
ditional equipotential bonding conductor connection on the housing.
4.9.5 Solenoid Valves (Optional)
DANGER Explosion hazard when opening the solenoid valve housing
The solenoid valve is a closed system. It must not be removed!
A fuse suitable for the rated current (max. 3 x Ib per IEC 60127-2-1) or a protective motor switch with short circuit and fast
thermal response (set for rated current) must be connected upstream from each magnet to prevent short-circuits.
– For magnets with a very low rated current, a fuse of the lowest current value under the IEC standard will suffice. This fuse
must be connected separately, upstream.
– The rated fuse voltage must be equal to or greater than the specified nominal voltage (U
N
+10 %) of the magnet. The fuse rat-
ing is specified in the type plate of the solenoid valve.
– The limiting breaking capacity of the fuse element must be equivalent to or greater than the maximum short-circuit current
expected at the installation site (typically 1500 A).
DANGER Potential equalization/static charge
Static charges can result in incendive sparking.
Avoid static charges. All conductive probe parts must be earthed!
The housing has a connection for an earth/equipotential bonding conductor. Ensure the
housing is adequately earthed (minimum conductor cross-section 4 mm
2
).
Particularly also observe the requirements of IEC/EN 60079-14!
4.9.6 Limit Switch (Optional)
The optimal limit switch has a separate terminal box with terminals (terminal diagram see "Appendix").
14 Bühler Technologies GmbH BE460048 ◦ 08/2019