Reference Manual Rev 1.13
Page 16 004R-646-113
Figure 10: Cable Shield Connection
3.11.1. Cable Shield Connection and Earthing
Care should be taken when connecting shields to maximise EMC or RFI immunity
and minimise earth loops and cross-talk (interference) between instruments.
For full EMC or for RFI immunity, termination of the cable shields to the connectors
is very important. The earth lug of the instrument must be separately connected to
ground potential via a reliable link.
The AC power module directly connects the earth lug to the Earth Pin on the power
supply. In installations where earth is available on the power cable, instrument
earthing can be done with this connection.
The instrument should only be connected to earth via a single reliable link to avoid
earth loops.
Where each instrument is separately earthed, interconnecting cable shields should
be connected at one end only. This also applies to communications cable shields in
Ring Networks, refer to Short Ring Network and Long Ring Network connections
under Section 3.9.1 on page 12.
Caution: Some load cells connect the cable shield directly to the load cell (and
therefore the scale base). Connection of the load cell cable shield in this situation
may be site specific.
3.12. Regulatory Sealing Requirements
To comply with regulatory sealing requirements for each instrument, (i.e. to ensure
instruments are not accidentally or deliberately tampered with), it is important that
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