Messages

281

General Mach Discussion / How to handle servo faults

« on: September 22, 2013, 04:28:52 PM »

Originally I had planned to link the servo driver fault output into the e-stop circuit, so that if a driver faults out for any reason, the main power to all the drivers/spindle gets cut.
However, the issue with that is the drivers logic which is on a permanent 24V supply, would flag up a fault due to low voltage, meaning that to get them out of fault and power up the e-stop circuit, the drivers fault outputs would have to be bypassed, and a driver reset signal sent to all the drivers. Which although doable, would involve a few relays and a couple outputs.

To simplify things, I was thinking instead, just rely on the driver ready signal fed into the controller (I'm using a KFlop, so the controller itself can handle this and then report to Mach there's an issue) and halting motion if a drive enable signal fails.
I know it's not ideal, but then there are still limit switches to trigger an e-stop things if anything major goes wrong.

Does this sound feasible?

Also, I'd be interested to hear how others have servos wired up to deal with faults.

282

Show"N"Tell ( Your Machines) / Denford Cyclone retrofit

« on: September 21, 2013, 07:36:46 PM »

Whilst lounging about on holiday last month, this popped up on the radar

New Toy by mc_mtb, on Flickr

Once back from holiday, I had been planning to order all the bits to get my Matchmaker mill up and running, then look at getting something bigger to replace my little Conect lathe, however this Cyclone happened to pop-up just before I ordered anything.
My main reason for purchasing it, is it's a 35mm through hole version, which ties in nicely with my future plans. It also comes with a 6 position toolchanger.

Initially I was going to go a for a quick retrofit using a PLCM-E3 controller coupled with the PLCM-B1 BOB as the BOB is 24V tolerant, so connecting everything would of been reasonably straight forward, with the only other items needed being a couple stepper drivers, a bridge rectifier, and a big capacitor to give me a power supply for the steppers, however the PLCM stuff was out of stock in the UK with a lead time of two weeks. Also some reading up that the PLCM doesn't support threading, and all english pages disappearing from their website put me of using it.
Instead I've opted for a bit more involved retrofit, using the Dynomotion KFlop+Kanalog I had already bought for the mill, and fitting servos.

Here's the control cabinet prior to delivery -

Electrics as Delivered by mc_mtb, on Flickr
The original setup used an Optimised Controls rack fitted with a Eurostep controller, and rack mount Parker SD15 drives.
I spent some time today removing the old rack along with the wiring I know I won't need, and getting the Kanalog and servo drives mounted in place. I also managed to get an extra single phase contactor for the servo drives in place and connected into the E-Stop controlled supply.
As of this evening, this is how the control cabinet sits-

Out with the old, in with the new by mc_mtb, on Flickr

I'll hopefully start getting things wired up tomorrow.

283

Show"N"Tell ( Your Machines) / Re: Conect Contour Major Mill

« on: September 21, 2013, 06:31:21 PM »

Conect never used Denford software as far as I'm aware.

Conqueror Design who supplied quite alot of the original control boards to Conect still exist, and do offer an upgrade kit - http://www.eaziform.co.uk/index.php?products,cncupgrade
If your mill does use a Conqeurer board, then it's reasonably straight forward to convert to Mach.
You'll need 3 stepper drivers, a breakout board, and I think you'll need a 5V power supply, as I'm sure the original used 12V feed with onboard regulator to get 5V for the electronics. You may also need a few other components, such as an emergency stop/enable relay, as if the mill is anything like my Conect lathe, the e-stop button simply cuts the main power in.

284

General Mach Discussion / Re: one pop then another, no Gecko light

« on: September 05, 2013, 06:51:55 PM »

I'd guess the x-axis stepper wiring or stepper motor itself has a problem.

If the motor output from the Gecko goes open circuit while powered up, then chances are the drive will go pop. I'm not sure if a short ciruit would do the same, or if the current limiting would cut in before any problems occur.

It could be that when you've tried the spare gecko, the wiring/stepper fault has been present causing the drive to stay in fault, then when you've swapped the Y-axis drive across, the wiring/stepper has gone from good to bad and it's gone pop.
I'd check over the stepper wiring very carefully for any obvious faults, and if no obvious faults can be found, replace the wiring and possibly the stepper motor (consider how the cost of a new stepper stacks up against the cost of another trashed 201...)

285

General Mach Discussion / Re: Drilling 3 holes on a lathe

« on: August 16, 2013, 07:33:26 PM »

There's not really anything major I would change. Instead of using a M8 coarse bolt for the rear support, I'd probably swap to a fine thread just to make adjustment that little bit easier, but it's something that once set you don't need to touch.

I've not had any crash issues, but then I'm only using 3 pretty similar length stub drills and only moving between them. It's just a case of using a bit common sense, and making sure you retract far enough away to avoid any overlap issues.

286

General Mach Discussion / ITX Motherboard suggestions?

« on: July 15, 2013, 04:11:40 PM »

Has anybody got any recommendations for a cheaper and current ITX motherboard?

The popular ASRock PV540A is no longer commonly available (in fact, I'm struggling to find many ASRock boards commonly available just now), and I'm looking for a cost effective replacement.
I don't need a parallel port, so that does give me more options, but I'm just wondering if anybody has any recommendations.

287

Show"N"Tell ( Your Machines) / Re: Matchmaker Revival

« on: June 21, 2013, 06:57:25 PM »

After being distracted by another fairly major project for a few months, I'm now back on the Matchmaker.

The head got lifted back on at the beginning of March, quickly followed by the spindle motor.

Head On! by mc_mtb, on Flickr

I did manage to get some time to start stripping the old wiring out, where I discovered another terminal board buried in the back.
I know the machine had already been retrofitted once, so I'm guessing this board, which was behind the rear access panel, which itself had another control cabinet mounted in front of it, is from the original setup.

Internal Terminal Board by mc_mtb, on Flickr


After much crawling around, this evening I finally got all the old controller wiring out the main cabinet along with the old transformers/contactors, and the only wiring left coming out the back of the mill is for bits still attached the machine. One of the next jobs on the list will be tracing and marking all the remaining wires.

Final thing I done tonight, was wire up the spindle motor to the VFD and run the spindle up to speed. The high/low shifter works, and the varispeed works with minimal noise.


Next step in my plan is to start getting bits into the control cabinet. Just need to decide on what mini-ITX motherboard to use, as AS-Rocks seem to be hard to find of late.

288

General Mach Discussion / Re: My retrofit nightmare

« on: May 06, 2013, 11:55:37 AM »

First off, double check that you had the 5V connected up correctly, and the 5V is actually still 5V, as something on the powersupply side is the most likely thing to damage both boards.
There's no point looking at other issues, untill you are 100% confident that you have covered the basics (we all make stupid mistakes!)

Second, are the VFD connections in the diagram, the only connections you've made to the VFD (excluding the main power in/earth), and you've not connected the CN (Common) terminal to gnd at any point?
If you were to connect the Common terminal of most VFDs to ground, you can do a lot of damage, as most drives float this around mains voltage, so it would most likely damage something as soon as power was switched on. If you had done this, and you're power supply is protected by an RCD, the RCD should of tripped.

Other than those issues, I can't see anything else that could damage both boards. The C41 outputs are all opto-isolated (or at least they should be..) so any wiring issues on the output side should limit damage to that board, and any issues with the ESS wiring side is most likely to just damage the ESS itself, as I'd doubt enough current would get back through the ESS circuitry to put any major spike onto the 5V supply to damage the other board.

One other possiblity is something conductive i.e. a bit swarf/filing/stray screw/nut/washer has got on somewhere and shorted something it shouldn't off, but then that shouldn't of killed both boards, unless it caused an issue with the 5V supply.

289

General Mach Discussion / Re: My retrofit nightmare

« on: May 06, 2013, 07:46:20 AM »

Most of the cnc4pc documents are available online - http://cnc4pc.com/Tech_Docs/JINAN2ESS.pdf

That is a regulated power supply. Are you sure that you never got the + and - wires mixed up?

290

Show"N"Tell ( Your Machines) / Re: Chiron FZ12 on its way sometime soon(ish)

« on: March 29, 2013, 05:59:15 PM »

Summer? what does that mean, seem to recall that word from my childhood but havent heard it for years

It's that day usually around May/June, where that big yellow thing appears along with blue skies, and the temperature reaches double figures beginning with a two.
I'd personally just be happy to reach double figures right now!