ETAS ES930.1 - Example; Electrical Isolation; Fig. 6-3 Maximum Input and Common Mode Voltages

ETAS Analog Input Channels ("AI 1-4"/"AI 5-8" Connections)
ES930.1 - User Guide 48
Fig. 6-3 Maximum input and Common Mode Voltages
6.4.2 Example
The input voltages U
inx
, U
iny
, U
inz
and the common mode voltage U
CMxy
are pre-
defined. The maximum permissible common mode voltage U
CMyz
is to be cal-
culated.
U
inx
= 10 V
U
iny
= 5 V
U
inz
= 10 V
U
CMxy
= 15 V
max (U
inx
+ U
iny
+ U
inz
+ U
CMxy
+ U
CMyz
) = 60 V
10 V + 5 V + 10 V + 15 V + max (U
CMyz
) = 60 V
max (U
CMyz
) = 60 V - 40 V = 20 V
6.5 Electrical Isolation
The analog input channels are electrically isolated from each other. Each ana-
log input channel is electrically isolated from the supply voltage and from the
housing of the module.
+
-
+
-
+
-
Kanal x
Kanal y
Kanal z
Galvanische Trennung
Galvanische Trennung
Gehäusemasse
C
C
C
C
C
C
U
in+
U
in+
U
in+
U
in-
U
in-
U
in-
U
inx
U
iny
U
inz
U
CM x y
U
CMy z
U
c
U
c