VEGA VEGADIF 34 … 51 - Manual (Page 39)

VEGADIF 34 … 51 39
20094-EN-030731
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1
+
2
-
3
+
-
Electronics powered by a VEGA signal conditioning instrument
Ammeter for local testing
Transmitter
terminals
0/4 … 20 mA
U
Kl
U
S DISBUS
U
K
4 … 20 mA
R
X
If the differential pressure transmitters are operated on a VEGA signal conditioning instrument,
you have to connect the sensor via a resistor acc. to the following chart (see next page) to the
signal conditioning instrument during the HART
® adjustment. Together with the inner resistance
of the signal conditioning instrument, the resistance value of 250
Ω
required for the HART ® instru-
ment is reached.
If the resistance of the processing system or the power supply is more than 250
Ω
, then no
„adjustment resistor“ required.
1
+
2
-
3
+
-
~
+
-
Set-up
Ammeter for local testing
analogue / digital indicat-
ing instrument
Transmitter
terminals
Power supply
(Ri < 250
Ω
)
4 … 20 mA
U
Kl
U
A
U
S
R
X
U
K
Electronics powered by a power supply unit
Note:
An ammeter for local testing of the output current can be connected between terminal 1 and its
tag. This measurement can be carried out during operation without interrupting the supply ca-
ble.