Gb 6. commissioning, operation – WIKA S-20 User Manual

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WIKA operating instructions pressure transmitter, model S-20

14043170.02 07/2014 GB/D/F/E

6. Commissioning, operation

6.2 Electrical mounting

Only use original accessories. For accessories see data sheet PE 81.61.

WARNING!

The instrument shield does not act as a protective conductor for protection of personnel, rather as a

functional ground in order to shield the instrument from electromagnetic fields.

6.2.1 Connection assembly

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For instruments with ratiometric output signals, a shielded cable must be used. The cable shield must be grounded,

if the cable is longer than 30 m or leaves the building.

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Use a cable with suitable characteristics for the particular operating conditions.

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For cable variants, strain relief must be employed.

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Cable with ventilation tubes must be vented to atmosphere.

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The instrument must be earthed via the process connection!

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Select a cable diameter that matches the cable gland of the plug. Make sure that the cable gland of the mounted

plug has a tight fit and that the seals are present and undamaged. Tighten the threaded connection and check that

the seal is correctly seated, in order to ensure a tight seal.

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For cable outlets, make sure that no moisture enters at the cable end.

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Pin assignment see test report.

6.2.3 Setting up a voltage supply

The voltage supply is made via a power supply unit or a control unit which provides the energy limitation.

The power supply for the pressure transmitter must be made via an energy-limited electrical circuit in accordance with

section 9.4 of UL/EN/IEC 61010-1, or an LPS to UL/EN/IEC 60950-1, or class 2 in accordance with UL1310/UL1585

(NEC or CEC). The power supply must be suitable for operation above 2,000 m should the pressure transmitter be

used at this altitude.