3 Installation
30 |
266 MODBUS® multivariable transmitter User manual 2105216 Rev. AB
Transmitter wiring
ABB strongly recommends the use of shielded 1.5 twisted pair or 2 twisted pair (with drain wire) cable for the communication
interface. For a distance up to a maximum of 4000 ft. (1219 m), the wire size should be between 22 AWG (0.35 mm
2
) and 18
AWG (0.8 mm
2
).
For supply voltage connections, ABB recommends the use of a shielded twisted pair cable. For a distance up to a maximum of
4000 ft. (1219 m), the range of wire size could be between 18 AWG (0.8 mm
2
) and 14 AWG (2.1 mm
2
).
Cable entry points, and front and back housing covers are depicted in Figure 25.
DANGER - Risk to life due to explosion.
In an explosion-proof or flame-proof installation in a hazardous area,
do not remove the housing cover while power is connected due to the risk of an electrical spark. Sparking could
result in an explosion.
Before removing the wiring cover (rear housing cover), disconnect the equipment from the supply voltage and
take suitable measures to prevent reconnection.
Explosion-proof and flame-proof installations require explosion-proof conduit and poured seals or flame-proof
rated cable and cable glands, respectively.
Figure 25: Housing covers and cable entry points
The transmitter requires a supply voltage between 10.5 and 30 Vdc. Avoid cable installation in the vicinity of other power lines
(with inductive loads) or large electrical installations.
1.
Unscrew the transport screw plug from the cable entry if not already removed.
IMPORTANT NOTE:
These cable entries have a 1/2 inch NPT or M20 x 1.5 female thread. Various adaptors
and bushings can be fitted to these threads to comply with plant wiring (conduit) standards.
2.
Remove the rear housing cover from transmitter if not already removed (go to section 5.2,
for additional instructions).
Wiring cover
Display cover
Display cover
½
–14 NPT or M20 x 1.5"
cable entry port
½
–14 NPT or M20 x 1.5"
cable entry ports
Summary of Contents for 266 MODBUS
Page 163: ......
