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Messages - battwell

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Galil / Re: galil thc
« on: January 06, 2010, 06:46:14 AM »

see dthc section

basically it requires an analogue input to read from a voltage divider circuit ( 0-400v dc at torch cathode output divided down to give 0-10 v at galil input)
the operator sets initial pierce height (variable for different material/thickness etc) above the metal which is higher than the cut height, also a variable parameter set by the operator for material to be cut.

the plasma should have a floating head with height rference switch  touch off on it. ( z reference lowers the torch, in switched off condition to metal . the torch continues down until it activates the the z reference switch fitted to the floating head. at this point the z is raised by the travel of floating head to z ref switch plus pierce height to give correct pierce height above the metal

an output is then given to the torch on relay. starts plasma arc and pierces metal
the plasma outputs an arc ok signal back to control to tell control it is on once arc is established
the control dwells for a parameter set time (to allow full pierce of the material)
the z is now lowered to the parameter set cutting height
motion commands given to start cutting movement

during movement the voltage divided signal is referenced continually and any change moves the torch up or down to keep the arc at the precise voltage.
the voltage / current loop is what makes for a perfect cut.
this movement must be virtually instantaneous to keep the arc set as required.

also this needs to be able to be disabled or reduced at very  slow feed rates ie tight corners to stop the torch diving down into the metal in corners where it is cutting faster than its moving

Galil / Re: galil thc
« on: January 05, 2010, 07:48:42 PM »
has anyone got this right on the galil yet? if so can you share your code

Galil / Re: Mitsubishi HF-SE Ac servos and drives.
« on: December 11, 2009, 07:21:55 PM »
i buy any mitsi i can get cheap on ebay. mr-h, j2, or j2s . they are all good! the h series have to be hard wired as plugs are virtually impossible to find!
i started off with 2 mr-h series 2kw drives for £10 each which got me intrigued so i had to learn about them, and man there was a huge learning curve!
the hardest thing is making a pair as there are loads of drives and loads of motors coming up all the time. the mitsubishi drives are motor wattage specific and not forward compatible. so a j2 wont drive a mfs or kfs series motor but are backward compatible so the j2s series will happily drive a mf or kf motor etc. they use serial encoders which transmit model and motor info so a wrong combination just shows an error alarm.
the encoder passthrough is a great way to slave servos too without using further outputs from mach etc, with the j2s this can be done serially too!
the older motors have resolutions as low as 8192/rev the newer motors up to 15 bit. (130000 odd)  either has plenty of resolution for mach/ galil mills etc
i probably have a collection of over 100 "pairs" here now ranging from 053 to 2kw sizes.
up to 750 watts can be run from single phase 230volts. higher than that your into 3 phase.
i got fed up losing steps on a mini boxford lathe so i fitted servos 053 with j2s drives (£100 per pair roughly) total accuracy now!
the 2kw drives i have will be going into my refit of a 3metre biesse router but im setting it all up using the old dc stuff with galil first so i can still use the old controller until its done! this old 1993 machine has 500ppr encoders and still gives pretty good accuracy. by the way 2kw is the output of the starter motor on my mercedes sprinter so you can imagine the torque these things produce!
the 400 watt size are great for a medium sized router , plasma etc. if work didnt keep getting in my way i would have my plasma table finished by now!

Galil / Re: Mitsubishi HF-SE Ac servos and drives.
« on: December 11, 2009, 04:31:44 AM »
i tested my galil 1750 last night  with mitsubishi j2 series drive. both in step mode (position) and analogue (speed)
in speed mode setup as below
first of all in speed the motor vibrated like hell when switched on. changing kd to 1 instead of 6 in galil tuning sorted this straight away.
i left the default encoder passthrough counts as 4000 quadriture on the mitsubishi. only used a b a nd z encoder outputs
all i can say is what a combination! so smoothe !!!
using the tell error function at any time during motion it was never ahead or behind by more than a few encoder counts. as soon as it stopped the motor always -1 counts so absolutely spot on and in position! (i ran full speed range on the servo with accelerations / dec from 0 to 2 seconds)
conclusion?  amazing combination!
with so many really cheap yaskawa and mitsubishi drives and motors on ebay why bother with old dc stuff you have to try to attatch encoders to etc. obviously unless refitting an old dc drive machine. if you find during a refit or later that one of the old dc drives is a let down, go for the mistsi as a replacement!

General Mach Discussion / Re: minimum spec for pc with galil
« on: December 10, 2009, 08:04:16 PM »
im running an old 400mhx amd fine with a 1750 and mach
but i also purchased a 2.8 gig motherboard from china genuine intel with isa slot. including 1 gig ram and processor for $99 posted to uk. works great after a week finding the right motherboard drivers! which i have if you get one. just search intel isa on ebay, worldwide.
im buying 4 more off the guy as i have 5 1750 cards etc here bought for peanuts on ebay too.

Galil / Re: older isa bus galil with mach 3
« on: October 01, 2009, 01:13:46 PM »
thank you.
i did email galil but didnt get a reply

Galil / Re: older isa bus galil with mach 3
« on: September 29, 2009, 06:59:33 PM »
does the cb 1500-100 require a cable or does it plug directly onto the 100 pin out of the optima card?

Galil / Re: older isa bus galil with mach 3
« on: September 29, 2009, 06:49:15 PM »
interesting! hadnt seen them on galil site. i still have to get cable anyway.
thanks again  kcrouch for helping with the almost purchased non compatible cables,

il get the right ones from galil eventually once ive confirmed and prototype tested a few things on my machine
just didnt want to spend lots in the test stage.

time galil had an ebay shop so i could order easy and pay with my paypal account. im sure they would have a lot of excess stock kicking around.

Galil / Re: older isa bus galil with mach 3
« on: September 27, 2009, 04:17:36 PM »
sent you a pm. thanks for your help

seems im at a halt until i can get cables and breakout boards to uk.

Galil / Re: older isa bus galil with mach 3
« on: September 27, 2009, 11:37:05 AM »
what do you use to tune servos? i cant get galiltools to recognise the 1750 card? recognises straight away in smarterm.
quite happy to buy galiltools if i can get it to recognise card.
didnt particularly want to spend lots of bucks on wsdk only, unless someone wanted to make me a donation of it.

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