retrofit on EMCO PC turn 55

OK the first sounds like a standard one channel spindle plus index encoder so should connect to the 7I76s encoder input directly

The tool changer inputs may either need a level shift or perhaps a trick with the 7I76s analog inputs

I can easily convert them to 24v with a transistor and a resistor (resulting in inverted output), but I had imagined there would be some super-standard IC with a Vcc of 24v.

Note that the spindle encoder needs to go the the 7I76 encoder inputs, so you really only have 2 inputs to convert

Since these are on the tool changer and are slow, I would be tempted to do a zero hardware patch
and connect them to inputs 0 and 1 on the 7I76 and read them as analog voltages, then put the analog
voltage through the compare component to get a bit (set threshold to 1/2 way up or 1.8V)

Eventually when we have 5V input options in the firmware this can be cleaned up

The Emco spindle encoder has an index pulse and phase A which is 100 pulses per rev. In my original wiring I used a 7409 open collector to level shift from the 5 volts to the G540 inputs which contain a +12 volt internal pullup. After looking at a datasheet it appears even +12 is exceeding the 7409 specifications of max output voltage.

When I added a second parallel port, I connected the spindle outputs and tool turret outputs directly to the second parallel port without a BOB because they are 5 volt signals and have the internal signal conditioning circuitry.

Chuck


I have an EMCO PC turn 50 which is pretty much the same as the turn 55 i think, except maybe the spindle motor on yours may be three phase, is that correct? Mine is all single phase 110V


any way I am still running the fan0t control and have always had trouble with the tool turret, when I program a tool change it will try to change and then error out, all it says is fatal error?


any idea what that may be caused by, I would like to sell this lathe but I may have too much money tied up in it to sell with out it working correctly.


if you have any pointers about the turret please let me know,


Thanks


Bob

My PCturn 55 has a very nice 3 phase motor. I completely scraped all the existing electronics including the VFD. I am using a TECO VFD which works quite well.

I cannot provide any insite on the original software as I do not use it.

I am using a stock tool turret, including the original DC motor and control board. The turret has two sensors. One indicates tool 1 and the other pulses as the turret rotates. I wrote a component to control this turret using LinuxCNC.

Thanks Chuck


I will have to dig a little deeper and see if I can figure it out , or do the discount sale to get rid of it

any idea what they are worth, probably alot less than I gave for it:angry:


Bob

I agree andy but I would rather spend the money on the hnc lathe that I have been obsessing over

these last few days.



getting closer to deciding what to do.



Bob