Machsupport Forum

Mach Discussion => General Mach Discussion => Topic started by: tpworks on December 14, 2007, 10:28:35 PM

Title: spindle speed encoder conection
Post by: tpworks on December 14, 2007, 10:28:35 PM
I have been having a time trying to get my spindle up to speed with the cncpc c6 board. I can get the spindle to start but can't get it up to speed.
tried the spindle tuning and it takes off full throttle and won't turn off. I click the spindle off and it goes full out and when I click it again it slows down(the on state)click the down rate and shuts off. so I thought if I put an encoder on the motor I could have control. Question is how do I tell mach3 where to look , I connected encoder outputs A to pin12 and B to pin 11.
Title: Re: spindle speed encoder conection
Post by: Hood on December 15, 2007, 04:47:00 AM
You  cant use an encoder on the spindle, what you need is  a single pulse for the spindle speed. The Index pulse from a normal encoder is too short so the best idea is to get an optical switch and have a slotted disc (1 slot) then put the single input as the Index.
Hood
Title: Re: spindle speed encoder conection
Post by: tpworks on December 15, 2007, 08:24:03 AM
Hood,
 Thanks for the reply. I was sort of expecting that but I just wanted to be sure I wasn't missing something somewhere.

Thanks
Tom
Title: Re: spindle speed encoder conection
Post by: jimpinder on December 15, 2007, 02:41:14 PM
You can do it even more simply.  If you scan the posts it came up a short while ago. I bought an optical transmitter and receiver all in one - they are set at a V angle. You shine it on the spindle (mine is on the chuck). As a reflector I "borrowed" a small shiny stick on from my grand-daughter. I painted the rest of the track matt black.

This is wired directly to the +5v and 0v for power - and one wire into the "index" input on the computer - no need even for the slotted disc.