Hi,
have been looking at the manual and found:
S-0-0032, Primary Mode of Operation
which sounds very hopeful because the nexy entry is:
S-0-0033 Secondary Operation Mode 1
Description:
The first secondary operation mode is reserved for the jogging operation
for DKC.
Any other auxiliary operating modes are not permitted.
so while is has a primary and secondary mode the secondary is reserved for on-drive jogging....bugger!
Your requirement are that you be able to perform indexable operations but also require max speed from the spindle. Even if indexing is not required at high
speed as you have only one mode of operation available to you then your solution is to choose the compromise between the two.
May I suggest that you keep the signalling rate to about 200kHz , beyond that and you will start encountering speed difficulties. You've already identified
one, the cheap optos used on breakout boards are unlikely to go anywhere close to 200kHz.
Say you assume a top speed of 3000 rpm...that is 50 revs/sec. 200,000/50=4000. So if you program your encoder to give you 4000 counts/rev then you can
achieve you max speed comfortably. 4000 counts/rev is an angular resolution of 360/4000=0.09 degree or 5.4 arc min, very acceptable. If that were direct
coupled to a 5mm pitch ballscrew it would be equivalent to a 1.25um linear resolution. Any man, hobbyist or not, could be proud of a machine that could turn
in that sort of resolution! The question is are you?
It is not necessary to set a high pulse rate to achieve smooth or quiet operation of a servo, that comes from the concept of microstepping which is a valid
technique to get smooth motion from a stepper motor.
The ESS will require a breakout board and I doubt the one you have will work well enuf. I use two break out boards from Homman Designs in Austrailia, I
live in New Zealand and as much as it pains me to admit it some of those bloody Aussies are really clever and relatively close, they don't have opto isolators.
You need to be a bit careful about what the various IO is hooked to so that power supplies don't fight but the speed is determined by the TTL buffers, easily in
the MHz range. Even if you get a breakout board without optos and with TTL buffers you will still need to use differential signalling and a twisted pair cable to signal
your drive at 200kHz or better. Are you electronically inclined? A simple line driver IC will do the trick over a few meters. Other than making one yourself you could
probably buy something pretty cheaply....they are really simple/small after all.
I have not used Mach3 turn. I know there is a feature that allows you to maintain a constant surface speed but as I say have not used it. I have done plenty of
manual turning over the years on all sorts of lathes none of which had infinitely adjustable speeds and I made plenty of good ********* on them. Is it that important?
Anyway the setup we're talking here can handle that easy.
While the servo software may run on a XP machine you should be able to set up your drive which is then programmed onto an EPROM and thereafter you don't
need the setup software at all. That's certainly how the Allen Bradley software works, I program the drive on any computer that has the Ultraware software on it
and the I take it away and put it on my mill which doesn't have the setup software on it!.
Craig
Guest
Show Posts