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System Description
WAGO I/O SYSTEM 750 XTR
750-333/040-000 FC PROFIBUS G2 12MBd XTR
Manual
Version 1.4.0
Example:
Calculating the total current on the Example Coupler described above:
A node with the example coupler, which is described above, consists of:
•
20 relay modules (750-517/xxx-xxx)
•
10 digital input modules (750-1415/xxx-xxx).
Internal current consumption
20 * 90 mA = 1800 mA
10 * 6 mA = 60 mA
Sum
1860 mA
The example coupler can provide 1620 mA (see previous example) for the bus
modules. This value is given in the associated data sheet. Consequently, an
internal system supply module (750-613/xxx-xxx), e. g. in the middle of the node,
should be added.
The maximum input current of the 24 V system supply is 500 mA. The exact
electrical consumption (I
(V)
) can be determined with the following formulas:
Fieldbus coupler or controller
I
(5 V) total
= Sum of all the internal current consumption of the connected
bus m internal current consumption fieldbus
coupler/controller
Internal system supply module
I
(5 V) total
= Sum of all the internal current consumption of the connected
bus modules at internal system supply module
Input current I
(24 V)
=
5 V
*
I
(5 V) total
24 V
η
η = 0.87
(87 % Efficiency of the power supply at nominal load 24 V)
Activate all outputs when testing the current consumption!
If the electrical consumption of a power supply point for the 24 V system
supply exceeds 500 mA, then the cause may be an improperly
dimensioned node or a defect.
During the test, you must activate all outputs.