IFM Electronic ecomat 200 Monitor AL-3 Operating Instructions Manual page 25

The analogue current signals at both inputs can be scaled, displayed and moni-
tored independently of each other. The start and end values of the current signal
can be assigned any numerical value – corresponding to the measuring range of
the sensor (e.g. 4...20 mA = 0...25 [bar]).
The monitor compares the actual signal values with the set limit values and switch-
es the assigned outputs depending on the set parameter values and functions. The
analogue output provides the input signal IN 1 unchanged or scaled for further
use.
In the comparator mode the monitor AL-3 forms the difference or the total from
the two input signals (IN 1-IN 2, IN 1+IN 2). The differential or the total value can
be displayed, evaluated, compared with the set limit values, and provided as ana-
logue signal. The outputs switch according to the set parameter values and func-
tions.
The teach function enables the assignment of an actual signal value to a switch
point and detection of the value range of the analogue output.
pressure sensor B
e.g. filter system
limit value 2
e.g. ∆ bar
1
The AL-3 monitor only has one channel. By means of an electrical connec-
tion of the output of two or several units to achieve a redundant circuit, they
can also be used for safety tasks. The applicable technical standards must be ad-
hered to.
pressure sensor A
limit value 1
e.g. ∆ bar
2
switching outputs
MONITOR
Principle
comparator mode A-B
Limit and differential moni-
toring of 2 physical process
values by means of the sig-
nal combination A-B
here e.g. pressure [bar]
The measuring ranges and
output signals of the sen-
sors have to be identical!
display, evaluation
or recording
[∆ bar]
analogue output (A-B)
AL-3
25