Browse FAQs

What is the scaling of I motor when this variable is used in ATV32/320 logic?

Published date: 07 January 2019

The scaling of variables is derived from variables list in ATV.. communication variables.
However for some variables there are 2 ways for reading them by ATV logic, see picture.
If you read motor current from LCR, you will read the value in amperes with one decimal point. E.g. you will see value 60 when motor current is 6.0 A 
But if you read the value via logic input signal assigned to "I motor", the signal scaling is 8192 (range 0-8192), exactly like for AI1R, AI2R described in 
The value 8192 corresponds to drive size, exactly to 2-times max continuous drive output current. For example if you have ATV320U40N4B with 9.5A (see catalog data) max continuous output current, then 8192 corresponds to 19A. 
And if motor current is 7.0 A, the "I motor" signal value will be 7/19 * 8192 = 3018. 
Note that "I motor" signal values 3005, 3018, 3024 can also lead to LCR=7.0A because resolution in LCR (especially in small drives) is much lower than 13 bits (range 0-8192).

Was this helpful?

What can we do to improve the information ?