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How to Read the Raw Data of a Multi-turn Encoder when using the AKD Drive’s Primary Feedback X10

How to Read the Raw Data of a Multi-turn Encoder when using the AKD Drive’s Primary Feedback X10

Parameter FB1.P allows the user to read the position of the primary feedback device connected to X10. The position can be read as counts or in custom units. This is the raw position read back from the device. When FB1.PUNIT = 0 the output format is 32:32, the upper 32 bits represent the multi-turns and the lower 32 bits represent the position of the feedback. 

An example of how to read the feedback data:

FB1.PUNIT = 0  “FB1.P data size is 2^64 total data size. Bottom 2^32 is single-turn, Upper 2^32 is multi-turn.

FB1.P= 42949698610   If the FB1.P value is equal to this amount

Calculating Multi-Turns of Encoder:

Multi-Turns of the Encoder = FB1.P / 2^32

Multi-Turns 42949698610 / 2^32 = 10   The Multi-Turns of the encoder are always just the Integer without the decimal

Calculate Single-Turn Feedback Position:

Single Turn Feedback = FB1.P – Multi-Turns * 2^32

Single-Turn Feedback = 42949698610 – 10 * 2^32 = 38654731314 counts

An example of how to configure the FB1.P to custom units

FB1.PUNIT = 3   Allows the user to setup custom units

FB1.P scaling per one motor revolution =  FB1.PIN / FB1.POUT

FB1.PIN= 10000 / FB1.POUT = 1  Once per motor revolution = 10000 counts

FB1.P= 100342   If the FB1.P value is equal to this amount

Calculating Multi-Turns of Encoder:

Multi-Turns of the Encoder = FB1.P / 10000

Multi-Turns 100342 / 10000 = 10   The Multi-Turns of the encoder are always just the Integer without the decimal

Calculate Single-Turn Feedback Position:

Single Turn Feedback = FB1.P – Multi-Turns * 10000

Single-Turn Feedback = 100342 – 10 * 10000 = 342 counts

Comments

Arjun Sharma's picture
Arjun Sharma
How can I read FB1.P through EtherCAT PDO or SDO mapping?
kenny.hampton@kollmorgen.com's picture
kenny.hampton@k...
FB1.P is not accessible over EtherCAT with either SDO or PDO because it is one of the AKD parameters that does not have an object number.