Input Amplifier
The input amplifiers are used for adapting the
widely varying signals in the ambient world to
the measuring logic of the timer/counter.
These amplifiers have many controls, and it is
essential to understand how these controls
work together and affect the signal.
The block diagram below shows the order in
which the different controls are connected. It
is not a complete technical diagram but in
-
tended to help understanding the controls.
The menus from which you can adjust the set
-
tings for the two main measurement channels
are reached by pressing INPUT A respec-
tively INPUT B. See Figure 3-2. The active
choices are shown in boldface on the bottom
line.
Impedance
The input impedance can be set to 1 MW or
50 W by toggling the corresponding softkey.
CAUTION: Switching the impedance
to 50 W when the input voltage is
above 12 V
RMS
may cause perma
-
nent damage to the input circuitry.
Attenuation
The input signal's amplitude can be attenuated
by 1 or 10 by toggling the softkey marked
1x/10x.
Use attenuation whenever the input signal ex-
ceeds the dynamic input voltage range ±5 V or
else when attenuation can reduce the influence
of noise and interference. See the section deal-
ing with these matters at the end of this chap-
ter.
Input Signal Conditioning
3-2 Input Amplifier
B
Fig. 3-1 Block diagram of the signal conditioning.
Fig. 3-2 Input settings menu.
To Next Page
Loading...
