Elumatec SBZ 130/01 retrofit

Your halfiles were very helpful, thank you I got my encoders spitting data.

How does encoder scaling work?

I have a magnetic linear encoder with 1 micron resolution (native 2mm pole distance with interpolation resulting in 1um resolution). My ball screw pitch is 5mm per revolution, so should my encoder raw count be 5000 pulses per revolution and the encoder scale 5000. The encoder spits some large number which seem to work in increments when I move the readhead but the readings are non sense large number like 254921 or similarly large number.
 

The scale should be 5000 if the scale resolution is 1 uM
With a scale of 5000, does the position (not the count) change by
1.000 for each mm of motion?

Other possible issues for add position numbers are wrong BISS setup parameters
or clock/data polarity issues.

does the position (not the count) change by
1.000 for each mm of motion?

Yes. For small distances, the readings increase by correct amount. In my case starting point X axis changes from -2366.005 -2365.008 moving 1mm.
When I swap tx+ and tx- the data output is same. swapping rx+ and rx- results in the digital read out showing a constant number.

biss_chan_0=xencoder%26ge

setp hm2_5i25.0.dpll.01.timer-us -200
setp hm2_5i25.0.stepgen.timer-number 1

setp hm2_5i25.0.biss.00.timer-number 1
setp hm2_5i25.0.biss.00.frequency-khz 2000
setp hm2_5i25.0.biss.00.xencoder.scale 5000
#setp hm2_5i25.0.biss.00.xencoder.counts-per-rev 130000

What are the readings at the far ends of the scale?
26 bits sounds a bit odd since that's 67 meters in microns...

( There may be some status bits included in the 26 bits that
need to be reflected in the format string )

 

26 bits sounds a bit odd since that's 67 meters in microns...

How does 26 bits translate to 67 meters?

What are the readings at the far ends of the scale?

The scale is not mounted on to the machine but its on the table and everytime the number shown in axis is different. Sometimes it is -20901 to -20768 and completely different number when placed again.

( There may be some status bits included in the 26 bits that
need to be reflected in the format string )

 

My encoder is 2D0. I tried biss_chan_0=xencoder%24ge after seeing first couple of bits are zero from the table I've attached but the readout in axis changes very minute decimal places while traversing the whole length of the scale with 24ge string.
 

2^26 * 1u = 67 meters

if there are 0 bits in the data, they must be accounted for in the format string.
That is, if you still have 26 bits total, the format string must have 26 bits, not 24
some of them being dummy (using the "pad" format string entry) bits and not
part of the position part of the data

Do you have a link to the encoder manual?

Are you sure its Gray coded?

I think their wording 26 bit binary format means its not gray coded.

RLS LA11: 

 


"biss_chan_0=null%1bcrc%6fwarning%1berror%1bencoder%26e" I saw this in a forum post where a person posted he was using similar renishaw glass scale. Where is the information about the format string? man page for hm2 doesn't go into this much details. Also the string I mentioned above doesn't work for me, but the person in the forum said it his scale is working.

Yes, your scale uses 34 bits rather than just 26 bits so that string looks closer.
you need 24 bits of (non Gray code) position, 2 pad bits, 1 error and 1 warning bit
and 6 CRC bits

The hostmot2 manual page describes the format string components in the SSI section