Dynomotion Forum

Hi tom,

I am using KFLOP+Kanalog+Konnect, and currently i am using servo motor with 5000ppr incremental encoder.

I want to use servo with in built 23bit Absolute encoder, with kflop, what connections has to made, here is the servo motor and drive that i am using.

http://leadshine.com/productdetail.aspx ... 00lh60f-ss

and drive LEADSHINE ELP 750RS version.

Because with absolute encoder, no homing required on power on/off. am i right?

Waiting for your kind reply.

Hi Amit,

You would have to research the interface specification. I'm guessing Modbus?

If so it would be too slow to use instead of the incremental encoder but could be possibly used on power up to avoid homing.

One way is to use the analog input and connect the drive as a normal analog servo drive and every time you initialize, read the absolute drive position, via modbus and assign the position to current kflop position with the Pos<ch>=xxx.x command.

TomKerekes wrote: ↑

Fri Jan 29, 2021 5:04 pm

Hi Amit,

You would have to research the interface specification. I'm guessing Modbus?

If so it would be too slow to use instead of the incremental encoder but could be possibly used on power up to avoid homing.

Hi tom,

Thanks for the reply.

Modbus is the interface that is required by leadshine servo drive, how to interface the modbus with kflop ?

I want to avoid homing on power-up, that's why going for absolute encoders.

Is it possible to read absolute position of encoder using modbus, if yes then how ?

Waiting for your kind reply.

For ModBus see here.

TomKerekes wrote: ↑

Mon Feb 01, 2021 2:18 pm

For ModBus see here.

Hi tom,

Thanks for your reply.

I have studied that link that you shared, but i can't find that, How do i read the current absolute position from the drive, so i can avoid homing ??

I have connected kanalog rs232 to drive rs232 via cable., Is there anything that i am missing ?

I just want to receive data, i don't want to send any data to the drive.

Waiting for your kind reply.

Modbus typically works with 16-bit registers that can be read or written. Read the manual for your drives and determine which registers contain the data you need. Then connect your Drive to a PC (not Kanalog) and use the PC example in the link to verify you can read them.

If you need to communicate with more than one drive you will need a rs232 to rs485 converter. Go to page 159 on the leadshine manual there is a description of the modbus protocol.In page 133 you wil see the address of the motor position register which is the 0x602C and 0x602D, which is propably the absolute encoder position you need.

cnc_freak wrote: ↑

Tue Feb 02, 2021 10:04 pm

If you need to communicate with more than one drive you will need a rs232 to rs485 converter. Go to page 159 on the leadshine manual there is a description of the modbus protocol.In page 133 you wil see the address of the motor position register which is the 0x602C and 0x602D, which is propably the absolute encoder position you need.

Hi there, thanks for your reply.

But how do i read that position register from leadshine servo drive to KANALOG rs232 pin, or any c program suggestions??

Waiting for your kind reply.

TomKerekes wrote: ↑

Tue Feb 02, 2021 4:17 pm

Modbus typically works with 16-bit registers that can be read or written. Read the manual for your drives and determine which registers contain the data you need. Then connect your Drive to a PC (not Kanalog) and use the PC example in the link to verify you can read them.

Hi tom,

thanks for your reply, i tried it using pc and it is working as it should, i am able to get position register data using modbus cable, but i am not able to get same data using kanalog, how should i proceed now ?,,

Any c programming suggestions to read position register using rs232 connector in kanalog.

waiting for your kind reply.