Connecting An Active Current Source; Connecting A Passive Current Source - Endress+Hauser Ria251 Bedienungsanleitung

3.2.1 Connecting an active current source

E.g. a sensor with its own power supply and active current
output.
If a respective barrier is used the display can be installed
directly in the explosion hazardous area.
Terminals 2 and 4
internally linked
+
Y
-
I

3.2.2 Connecting a passive current source

E.g. Transmitter with additional loop power supply.
(The unit as front end display):
An Ex-certified process display can be applied as a front end
display in the non-explosion hazardous area.
-
+ E
1 3 4
2
+ -
Process display
21