Beckhoff ELX3351, Руководство по эксплуатации

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Parameterization and programming
ELX3351 34 Version: 1.3.1
• Parallel operation of load cells is possible with the ELX3351. Please note:
◦ Load cells approved and calibrated by the load cell manufacturer for parallel operation should
be used. The nominal characteristic values [mV/V], zero offset [mV/V] and impedance [Ω, ohm]
are then usually adjusted accordingly.
◦ A 6-wire connection is expressly recommended.
◦ All the relevant operating parameters (e.g. the minimum bridge input resistance)
must be observed.
Fig. 26: Parallel connection with ELX3351
◦ Load cell signals have a low amplitude and are occasionally very sensitive to electromagnetic
interference. Considering the typical system characteristics and taking into account the
technical possibilities, purposeful state-of-the-art EMC protective measures are to be taken.
If shielded cables are used, the installation measures and, if necessary, the Separation
distances in accordance with IEC 60079-11 and IEC 60079-25 must be taken into account.
Under high EMC interference loads, it can be helpful to remove the cable shield in front of the
terminal additionally with suitable shielding material.