D122.A
2 Operation instructions
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2
Digital Indicator D122.A
2.1 Short description
The digital Indicator D122 indicates measured values of intrinsically safe current circuits from 4 up to
20 mA in hazardous areas. The device is powered by measure current, therefore an extra power sup-
ply or batteries are unnecessary. The indicator measures the current, scales the measured value and
displays finally the result on the LCD.
For trend analysis, the measured signal is also be displayed on a 41 segment bargraph. It's possible
to scale the bargraph separately to the digital value. The indicator D122 is available in several hous-
ings.
Furthermore with alarm monitoring option the indicator has two intrinsically safe alarm outputs. These
outputs change their state, when the measured value exceeds his alarm limits. It’s possible to choose
open-circuit or closed-circuit connection.
Additional the alarm limits appear graphically on a second bargraph. On one look you’re sure that the
measured value is in its limits.
2.2 Features overview
2.2.1 Basic functions
•
Loop-powered digital Indicator
•
Connect like passive analogue indicators, voltage drop ca. 1V
•
LC-Display up to 50 mm figure-height
•
Scale by buttons and display
•
Fast bargraph for trend observation (41 segments, refresh 4 times per sec-
ond)
•
Separately scaleable Bargraph (Zoom)
•
Several housings available (control panel- and field housing)
2.2.2 Options
•
Alarm monitoring: two intrinsically safe alarm outputs and an additional limit-
bargraph on the display
•
Limit-functions with hysteresis and time delay
•
Field housing with additional (2
nd
) PG-Connector
2.3 Conformity with Standards
The explosion proof indicators type D122 meets requirements of listed standards in the attachment
(Declaration of conformity). They were developed, manufactured and tested in accordance with state-
of-the-art engineering practice and ISO9001:2008.
