Retrofitting my maho mh400c

16 Mar 2010 02:03 #2315 by PCW
Replied by PCW on topic Retrofitting my maho mh400c
If they are sine wave scales (heidenhain?) you may want to use the original interpolators that came with them
otherwise you may lose quite a bit of resolution

16 Mar 2010 08:12 - 16 Mar 2010 09:08 #2316 by pirke
Replied by pirke on topic Retrofitting my maho mh400c
They are philips glass scales, somebody told me they were sine wave but i don't know for sure.
What do de original interpolators do? isn't there a sine to quadrature converter for sale somewhere?
Attachments:
Last edit: 16 Mar 2010 09:08 by pirke.

16 Mar 2010 09:24 #2317 by robh
Replied by robh on topic Retrofitting my maho mh400c
pirke wrote:

Then there's anothor problem, my linear scales dont put out a quadrature wave.
apparently they give a sine wave.
I've been told this could easily be fixed witch a custom circuit using a comparator, but i'm no electrical engineer...
I've found somebody who can build this for me but i wonder if there is a existing solutions for this.

hi
this would be true if its a sinewave per increment (ie. not a sinewave per turn of screw)as such then you can do Zero crossing on the sine way and feed it into a line driver for quad if you wish.

if its more like a resolver signal (sine wave over the screws turn), like pirke has drawn you need something alittle more advanced as then you will have Xnumber of puleses per turn,

hope the above makes some sence, once you know which you are dealing with, things will be easyer.
no dout if you tell us the part number on the scales, someone will take alook or know right away what type they are for you.

rob

16 Mar 2010 10:28 #2319 by BigJohnT
If it is a resolver then Pico has a converter for that.

pico-systems.com/motion.html

John

25 Mar 2010 18:19 #2443 by pirke
Replied by pirke on topic Retrofitting my maho mh400c
Well, they call this type of scale a resolver, i always call it an encoder but that is not correct since encoders give pulse signals i've been told.
its probably the same as the heidenhain scales.
I'll try to figure out what the signal is thats comming out of the scales.

What type of converter do you have? and does it interpolate the wave signal?

I think that if it works with the heidenhain scales it should work with the philips scales.

I have a conventional lathe with philips glass scales and a mill with heidenhain scales and they look basically the same.

25 Mar 2010 18:24 #2444 by pirke
Replied by pirke on topic Retrofitting my maho mh400c
And would i need 3 of the pica boards or is this one for 3 scales?

26 Mar 2010 19:12 #2455 by pirke
Replied by pirke on topic Retrofitting my maho mh400c
And then there's another thing...
The mesa 5i20 board is a pc/104 board.
I have absolutely 0 experience with pc/104, if there's a pci version that would be nice

26 Mar 2010 20:35 #2456
the 5i20 is pci.

sam

26 Mar 2010 20:44 - 26 Mar 2010 20:46 #2457 by pirke
Replied by pirke on topic Retrofitting my maho mh400c
skunkworks wrote:

the 5i20 is pci.

sam

woops

i was looking at the wrong card...
Last edit: 26 Mar 2010 20:46 by pirke.

29 Mar 2010 17:43 - 29 Mar 2010 17:44 #2471 by pirke
Replied by pirke on topic Retrofitting my maho mh400c
BigJohnT wrote:

If it is a resolver then Pico has a converter for that.

pico-systems.com/motion.html

John

Does anyone have any experience with these converters?
Last edit: 29 Mar 2010 17:44 by pirke.