User Manual

24 VEGAPULS 42 and 44 – 4 … 20 mA
Technical data
VEGAPULS 42 Ex or 44 Ex with pressure-tight encapsulated connection
compartment in four-wire technology
• Four-wire technology, supply and output signal via two separate two-wire cables for use in
Ex zone 1 (VEGAPULS …Ex) or Ex zone 0 (VEGAPULS …Ex0).
• Output signal 4 … 20 mA (active).
• Optional external indicating instrument with analogue and digital display (can be mounted
up to 25 m separated from the sensor in Ex area).
• Adjustment with PC, HART
®
handheld or adjustment module MINICOM (can be plugged into
the sensor or into the external indicating instrument VEGADIS 50).
• Load max. 500 W.
2
2
4
2
2
-
+
4 … 20mA
> 250 Ω
1)
If the resistance of the processing systems
connected to the 4 … 20 mA signal output is less
than 250 W, a resistor must be connected to the
connection cable during adjustment to get a loop
resistance of 250 W.
The digital adjustment signal would otherwise be
severely damped or short-circuited due to
insufficient resistance of the connected
processing system. Communication with the PC or
the HART
®
handheld would not be ensured.
VEGA-
CONNECT 2
VEGADIS 50 Ex
Ex area
active
2)
HART
®
handheld
Non Ex area
2)
4 … 20 mA active means that the sensor delivers
a level-dependent current of 4 … 20 mA (source).
The measuring signal of the sensor reacts
electrically to the processing system (e.g. display)
like a current source.