User Manual
GFK-2958J
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
OUT
+ Σ (I
= Cumulative current demand
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
Module 11 (without power refresh):
I = 8.19 A + (0.015 A + (0.5 A x 4) = 10.205 A
Therefore, the available 10 A would be exceeded. As a result, an EP-7641 power supply
module must be positioned as the 11th module, which will supply the required power to the
Configuration
+ (I
x g) module 1
L
+ (I
x g) module 2
L
+ (I
x g)) n modules
OUT
L
I
module current consumption from the output
OUT
current path
I
Current demand of the connected actuators
L
Chapter 3
Oct 2019
27