18 AWT210 |  2-WIRE CONDUCTIVITY, PH/ORP, PION TRANSMITTER  |  OI/AWT210-EN REV. 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 
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
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
AB
2
Connected internally
Non IS installations
9 to 32 V DC
IS installations
9 to 24 V DC
Functional earth
AB
2
Connected internally
Non IS installations
9 to 32 V DC
IS installations
9 to 24 V DC
Functional earth