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User Manual Section 3
GFK-2958L May 2021
Configuration 31
((I
IN
+ I
S
module x) x g)
+ ((I
IN
+ I
S
module y) x g)
+
Σ
((I
IN
+ I
S
) x g) n modules
= Cumulative current demand
I
SYS
Current consumption from the system current path
I
S
Power supplies for the connected sensors
Calculation of the Current Demand for the Output
Current
The current consumption of each module and the current demand of the connected
actuators must be considered for the output current. There is no difference in the
calculation of the main power supply and power refresh:
(I
OUT
+ (I
L
x g) module 1
+ (I
OUT
+ (I
L
x g) module 2
+
Σ
(I
OUT
+ (I
L
x g)) n modules
= Cumulative current demand
I
OUT
module current consumption from the output
current path
I
L
Current demand of the connected actuators
Example:
The values in the following table are used to calculate the current demand of the example
station (cumulative for each module). The input current is:
Module 1:
I = 0.116 A + (0.008 A + 0.012 A) + (0.06 A x 1) = 0.196 A
Module 2:
I = 0.196 A + (0.008 A + 0.012 A) + (0.06 A x 1) = 0.276 A
The values for the other modules are calculated accordingly. The result shows that the
accumulated value for up to 12 modules remains under 10 A, and therefore a power supply
module need not be used for the input current path. Results for the output current path:
Module 5:
I = 0.015 A + (0.5 A x 2) = 1.015 A
Module 6:
I = 1.015 A + (0.015 A + (0.5 A x 4) = 3.03 A
Module 10:
I = 6.175 A + (0.015 A + (0.5 A x 4) = 8.19 A