Technical Specifications
890CS Common Bus Supply - Frames B & D; 890CD Common Bus Drive and 890SD Standalone Drive - Frames B, C & D
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Electrical Ratings: : 890CS - Calculation
The required rating for the 890CS input stage can be calculated by adding up the sum of the motor
currents attached to the associated output stages.
For example:
if a 2.2kw,2 pole, 400VAC motor has a FLC of 4.59A,
and a 7.5kW 2 pole, 400VAC motor has a FLC of 14.2A.
Then a system with 4 x 2.2kw motors and 3 x 7.5kW has total load current of 61A, which is greater than
the 54A 890CS input stage rating. This example would need to use the next rating input stage, 108A.
But, if it is known that one of the 2.2kW motors is overhauled during normal operation, then that motor
current can be subtracted from, and not added to, the total load current.
In this case, total load current would be reduced to 52A. This is within the rating of the 54A 890CS input
stage.
