Starting, Operation - WIKA WU-20 Manual De Instrucciones

7. Starting, operation

Specific conditions for safe use in explosive atmosphere:
„ External earthing connection shall be established by end-user via pressure
connection minimum 4 mm² required. External earthing connection shall be
corrosion resist and locked against rotation.
Warning
Suitable connector minimum IP 54 shall be provided by end-user (In the
„
end-use application the degree of protection min IP54 shall be maintained).
If applicable the connector shall be in accordance with EN 60079-0:2006
and EN 60079-15:2005
Cable provided by end-user shall be suitable for the ambient temperature.
„
Use only shielded cables. Note that with connectors no connection between cable
„
shield and housing is possible.
For instruments with cable outputs, the cable is always shielded. Depending upon the
design (ordered version) the screen may or may not be connected with the enclosure.
An additional equipotential bonding maybe required.
„ Ensure that the cable diameter you select fits to the cable gland of the connector
Ensure that the cable gland of the mounted connector is positioned correctly and
that the sealings are available and undamaged. Tighten the threaded connection and
check the correct position of the sealings in order to ensure the ingress protection
Cover flying leads with fine wires by an end splice (cable preparation).
„
Please make sure that the ends of cables with flying leads do not allow any ingress of
„
moisture.
The transducer must be connected and operated in accordance with the approriate
„
regulations. Take care to ensure that the electrical connection (e.g. M12 connector) is
correctly made (fully sealed).
10 WIKA Operating instructions/Betriebsanleitung/Mode d'emploi/Instrucciones de servicio WU-2X
GB
7. Starting, operation
„ For equipment with Ex nA nL certification, or if operated under nA nL condi-
tions: Do not separate when energized.
Warning
The transducer is designed to operate with an input voltage of 10 ... 31 VDC / 14 ... 31 with
output signal 0 ... 10 V. The voltage value Ui = 31 VDC shall not be exceeded in the current
loop circuit. The interrelationship between voltage supply and load resistor (R
by the following diagram.
Signal output and allowed load
4 ... 20 mA, 2-wire
permitted
range
Current for external display- or evaluation equipment can be supplied directly from the circuit,
when operating a transducer with current output. A voltage drop specific to the display unit is
to be considered. The UHP-display unit of type (N)WUR-1 has a specific voltage drop of 6 V.
The transducers are short-circuit-proof for a short time, but anyhow any incorrect connection
of the instrument should be avoided.
WIKA Operating instructions/Betriebsanleitung/Mode d'emploi/Instrucciones de servicio WU-2X
GB
) is illustrated
A
Current output (2-wire)
4 ... 20 mA:
≤ (U+ – 10 V) / 0,02 A
R
A
Voltage output (3-wire)
0 ... 5 V: R > 5 kOhm
A
0 ... 10 V: R > 10 kOhm
A
with R in Ohm and U+ in Volt
A
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