VEGA VEGAMET 391 4 … 20 mA_HART - Manual (Page 14)

14
5 Connecting to power supply
VEGAMET 391 • 4 … 20 mA/HART
36032-EN-130701
10. For connection of additional relais to terminal strip 3, you have to
proceed as described earlier
The electrical connection is hence finished.
Remember that with Ex applications, the Ex separating wall must be
plugged onto the upper side of the instrument before setup.
Information:
•
On the active input (terminal 1/2), VEGAMET 391 provides power
for the connected sensors. Power supply and measurement data
are transmitted over the same two-wire cable. This mode is pro-
vided for connection of measuring transducers without separate
operating voltage (sensors in two-wire version).
•
On the passive input (terminals 5/6), the sensors are not powered
- only the measured value is transmitted. This input is for sensors
with their own, separate operating voltage (sensors in four-wire
version). On a VEGAMET 391 in Ex version, the passive input is
not available due approval-technical reasons.