Endress+Hauser RB223 Mode D'emploi page 33

3. Intrinsically safe operation of 2-wire transmitter (nonEx É Ex)
Fig. 9: Connecting a two-wire transmitter to RB223
Note!
!
1) A HART® modem can be connected to the HART® communication
jacks. The HART® communication jacks are internally connected to the
terminals "1+H", "2+" and "3-" and (in the case of a two-channel device)
"4+H", "5+" and "6-" (see »Terminal assignment« on page 26).
The resistance between the HART® communication jacks must be
between 230 and 600 Ω when using the HART® protocol (see »HART®
Transmission « on page 30).
7 Maintenance No special maintenance work is needed on the device.
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