ABB 2600T Pressure Transmitter Series, Руководство пользователя

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364xS User’s Manual 18
Installation
Wiring
HART hand-held communicator may be connected at any wiring termination point in the loop, provided the
minimum resistance is 250 ohm. If this is less than 250 ohm, additional resistance should be added to allow
communications.
Wiring requirements
For signal / power connection use twisted, stranded pairs of wiring no 18 to 22 AWG / 0.8 to 0.35 mm
2
Ø up
to 5,000 feet (1 500 meters). Longer loops require larger wire.
If a shielded wire is used the shield should be grounded only at one end, not both ends. In case of wiring at
transmitter end, use the terminal located inside the housing marked with the symbol:
Protective Earthing
Wire this ground connection marked with the symbol to a suitable earth ground.
For a transmitter measuring loop an earth ground should maintain a resistance of 5 ohms or less.
Use a heavy conductor, at least 15 AWG / 1,6 mm
2
Ø
WARNING !
A protective grounding connection is absolutely necessary to insure personnel protection, to protect against
surge and to prevent explosions in potentially explosive atmosphere.
WARNING !
The surge protection is always present and if the transmitter is installed in a Hazardous classified location, it
must be powered from a voltage source isolated from mains (galvanic separation). Furthermore the potential
equalization for the entire powering cable must be guaranteed since the intrinsic safety circuit of the
transmitter is grounded.
Hazardous
(Classified)
Location
Unclassified
Hazardous
Location