18
AW T 210 |
2- W I R E CO N D U C T I V I T Y, P H/O R P, P I O N T R A N SM I T T ER | O I/AW T 2 10 - EN R E V. C
…6 Electrical installation
Communication module connections
HART module
FOUNDATION Fieldbus module
Profibus PA module
Ground connection
Normal grounding practice is to terminate all grounds at the
control room side, in which case the field side of the screen
should be adequately protected to avoid contact with metallic
objects. The transmitter case should be grounded.
WARNING
Bodily injury
If conduit hubs are used, they will not provide a bonding of
the enclosure or system.
Referring to Figure 16, ground connections are provided:
internally
A
and externally
B
.
Figure 16 AWT210 ground connections
For IS systems the grounding should be at the safety barrier
earth connection. For bus-powered systems the grounding of
the screen should be close to the power supply unit. The
specific noise immunity and emitted interference are only
guaranteed when bus screening is fully effective – for example,
ensuring that screening is maintained through any existing
junction boxes. Appropriate equipotential bonding must be
provided to avoid differences in potential among the individual
plant components.
To ensure fault-free communication on Fieldbus (FF or PA)
installations, the bus must be properly terminated at both
ends. Only approved bus terminators must be used for
intrinsically safe circuits.
NOTICE
HART, Profibus and Fieldbus protocols are not secure.
Therefore, the intended application should be assessed
before implementation to ensure these protocols are
suitable.
Gland entries
For hazardous area installations, suitable Ex glands and
blanking elements must be used to seal the entry holes.
+
–
2
+
–
1
4
3
5
Power
Non IS installations
12 to 42 V DC
IS installations
12 to 30 V DC
Functional earth
Ammeter connection for loop current test
Ammeter
A
B
2
A
B
1
4
3
5
Connected internally
Non IS installations
9 to 32 V DC
IS installations
9 to 24 V DC
Functional earth
A
B
2
A
B
1
4
3
5
Connected internally
Non IS installations
9 to 32 V DC
IS installations
9 to 24 V DC
Functional earth
