# Panasonic incremental encoder

1. Jul 25, 2016

### Cdz

I have a Panasonic servo motor( model no.MSME 102GCGM), this motor comes with an encoder installed and a drive.
I am learning motor control, so i need to do the drive myself with dSPACE system and to do that I need the encoder signal as feedback, however the encoder output signal is not ABZ phase signal, rather it uses serial transmission which the Panasonic drive recognizes but the company would not share the protocol used.

To do this, the first thing, I need to know that protocol that is used for this encoder.

Second, after I know the protocol, I need to decode the information so that I can use it for motor control learning.

Am I right? It seems difficult. Anyone have some experience?
Or should I just buy another encoder with ABZ phase output?

2. Jul 25, 2016

### Tom.G

Really depends on how much time you have available. Reverse Engineering a protocol is doable but not always easy. With the right equipment it may take only a couple days. But I've seen projects where it takes months in complex cases. If you want to learn and you have the time, you can learn a lot by Reverse Engineering, even learn how to think more logically! So if you have the freedom to spend a week or so, give it a try. You may still end up replacing the encoder though.

3. Jul 25, 2016

### Baluncore

If this is a learning exercise then why be constrained by another complete integrated system.
Start from scratch with a lower power motor and the encoder of your choice. Keep it simple.

4. Jul 26, 2016

### Cdz

No it's not exactly just a learning exercise. For me, maybe it is, but for my professor it's not. It's a project and I do the basics to make sure the platform works and there will be more advanced work following.
But l like your idea, keep it simple. Neat.

5. Jul 26, 2016

### Cdz

I think Reverse Engineering is cool. I will try it and buy another encoder just in case.
Wish I make it
Thank you.

6. Jul 26, 2016

### Nidum

There is a reasonable chance that it uses SSI .

If not then it will likely be one of the more modern derived systems such as BISS[/PLAIN] [Broken]

In any case reading about SSI and BISS will tell you how these types of system work in principle .

Last edited by a moderator: May 8, 2017
7. Jul 26, 2016

### Cdz

I read that it is a 20bit incremental encoder and it has only two wires for transmitting signals named as $$PS \enspace\overline {PS}$$ and the manual says serial signal transmission.
I read on Wikipedia that both SSI and BISS have clock signal, so they are not what I am looking for.
So it may be something simpler.
I searched online and there is one guy said the protocol is just RS485. So I tried manually rotating the PM motor and checked the differential outputs of the encoder to look for the Baud rate of transmission.All that I get is a 50 Hz signal,whether I turn the motor or not.
I am supposed to get different outputs when I turn or don't turn the motor, right?
But it's the same. Any suggestions?

Last edited by a moderator: May 8, 2017