3. Cabling
3-7
TI 30A30A10-01EN
3.4
Connecting signal cable
3.4.1
Connecting signal cable (for CENTUM VP)
For CENTUM VP, the A2BN3D terminal block in the N-IO field enclosure interfaces with the field
devices.
SEE
ALSO
For signal cable connection for CENTUM VP, refer to the “CENTUM VP Installation Guidance” (TI 33J01J10-
01EN).
3.4.2
Connecting signal cable (for ProSafe-RS)
For ProSafe-RS, the field wiring terminal block in the enclosure interfaces with the field devices.
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Process I/O signal connection
• Power, control bus, and signal cables must be separately laid. Avoid laying them in parallel.
• In case of using multicore cables for field wiring, do not share one multicore cable with I/O
modules of different voltage types (i.e. 24 V DC).
• Use group-shielded twisted-pair cables specifically for noise countermeasures. A twisted-
pair cable pitch of 50 mm or less should be used and the shielded cables must be grounded.
• The use of twisted-pair cables is also recommended for digital signals.
• The twisted-pair cable has the following advantages over a solid wire:
- More flexible for easy curving and cabling in limited spaces.
• Signal cables must be clamped so that their weight does not affect terminals.
• Be careful not to apply excessive force to the cable when laying it.
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When mixing AI and DO in the same multi-core cable (N-IO I/O Unit)
When mixing analog input (AI) signal and digital output (DO) signal in the same multi-core cable,
take the following influence from DO pulse diagnostics or ON/OFF operation into consideration.
• The accuracy for Analog input function may be worse by several tens of μA depending on
the type, length of a cable and DO load current.
• A delay may occur in updating the HART event.
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Spring clamp terminal, Push-in terminal
CAUTION
• The N-IO field enclosure for ProSafe-RS uses a spring clamp terminal and push-in terminal
for signal connection.
• For cable connection with a sleeve attached, use a sleeve and a clamp tool from the same
manufacturer.
• Use a clamp tool which suits the cable thickness.
Feb. 26, 2018-00
