Re: [Emc-users] polyurethane resin casting
On Mon, 30 Sep 2013 17:33:55 -0700, you wrote: On Mon, 2013-09-30 at 18:23 -0600, Gregg Eshelman wrote: How about trying a different resin? Call Smooth-On and see if they have any recommendations that may fit your needs. Or perhaps an epoxy might work better? There are many manufacturers of those. One that looks like they have some interesting products is West Systems. West Systems is well thought of in the boating world. Nice easy ratio for catalyzing. Fairly long open times. I've used West epoxy resins quite a bit, both lay up and vacuum bagged. It works very well and there is extensive help and documentation on their web site. It's a lay up resin, not a casting resin. If you mix a paper cup of the stuff and leave it, it gets so hot it will burn the cup and catch fire - done it :) A friend of mine has a molding company and they use West epoxy a lot. Bubbles, if introduced are by poor mixing technique or out gassing from the mold. Epoxy gets hot as it cures, any air or moisture in the mold material will cause bubbles in the finish as it heats up during curing. Resin based molds should be post cured during their manufacturing process to a higher temperature than the curing temperature of the resin otherwise the mold will distort. His epoxy moldings are oven cured at 60C low vacuum (5lbs), some of the aerospace and automotive carbon fibre work he does is at 150C + and high vacuum. Having said that West epoxy also cures fine at room temperatures, just takes longer. Steve Blackmore -- -- October Webinars: Code for Performance Free Intel webinars can help you accelerate application performance. Explore tips for MPI, OpenMP, advanced profiling, and more. Get the most from the latest Intel processors and coprocessors. See abstracts and register http://pubads.g.doubleclick.net/gampad/clk?id=60134791iu=/4140/ostg.clktrk ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
[Emc-users] Crowbars
The PSU on my milling machine blew up again last night. This is the second time it has happened. I haven't pulled the box out of the machine yet, but I expect to see this again: https://picasaweb.google.com/lh/photo/xxfP_tT7Ae0op6GxUhSDvtMTjNZETYmyPJy0liipFm0?feat=directlink Which is a power resistor that has got so hot that it has exploded. (quite an odd failure mode for a resistor). The PSU is home-made and consists mainly of a bunch of capacitors and rectifier. Also in the box are two relays, two power resistors and a timer circuit. One resistor is a soft-start on the AC input side. When power is first applied the power passes through one of the resistors to limit the surge current, and then the timer closes a relay that short-out that resistor. I am fairly happy that that part of the circuit is reliable. A second relay is used in change-over mode. This has a 240V coil connected to the incoming power. When the PSU is powered up the relay closes, and supplies power to everything else inside, when the power goes off the relay opens and the NC contacts connect a crowbar resistor across the capacitors to discharge them. I think that the failure mode is that, in the case of a power glitch, the crowbar relay switches and is discharging 300V DC at a fair current, then the power returns and the NC contact tries to break 300V 10A and welds the NC contacts closed. Then the NO contacts close and we now have the crowbar resistor connected directly across the rectifier output. The crowbar resistor is not sized for continuous operation. I think that there are two problems here. If the crowbar contacts on the relay are welded shut then the power contacts should not be able to close. I think I need a more explicitly interlocked relay. Currently I am using: JG64U here: http://www.maplin.co.uk/round-base-10a-relays-2567 I think that the term I need to search for is force guided but would like some confirmation that that means what I think it means. Are contactors more dependable in this sense? The real problem is that the relay is not capable of breaking 300VDC. However, DC rated contactors are pretty expensive, and seem to jump for 220 to 44 and then 690V. I don't think I have room in the box for the big ones. I wonder if http://uk.rs-online.com/web/p/contactors/4111687/ would be OK? It really should never try to break with the capacitors charged (interlocked in HAL, which can see the DC bus voltage, and with the crowbar in circuit the voltage will drop pretty quickly anyway) My inclination is to look for a solid-state solution, but solid-state isn't very good at doing anything at all on the basis of the power going off -- atp If you can't fix it, you don't own it. http://www.ifixit.com/Manifesto -- October Webinars: Code for Performance Free Intel webinars can help you accelerate application performance. Explore tips for MPI, OpenMP, advanced profiling, and more. Get the most from the latest Intel processors and coprocessors. See abstracts and register http://pubads.g.doubleclick.net/gampad/clk?id=60134791iu=/4140/ostg.clktrk ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] polyurethane resin casting
So far, I have realized a number of mistakes. #1. I didn't wax the modeling board the first round, so the silicone surface is much too porous. Because of this, the surface releases bubbles during molding process and any residual moisture causes issues as well. #2. The back suction action starting at gel?? time has to be considered, and material in place to handle it. I built a mold out of delrin for testing, and find that bubbles are far less a problem, almost non existent with the slow set material. #1 is deduced from this, in part. I still would like to try aluminum, but would have to outsource it. Firstcut seems pricey, http://www.firstcut.com/FirstQuote.aspx?p=574441wmiu http://www.firstcut.com/FirstQuote.aspx?p=574440fsir On Wed, Oct 2, 2013 at 4:20 AM, Sven Wesley svenne.d...@gmail.com wrote: 2013/10/2 Steve Blackmore st...@pilotltd.net' ... I've used West epoxy resins quite a bit, both lay up and vacuum bagged. It works very well and there is extensive help and documentation on their web site. It's a lay up resin, not a casting resin. If you mix a paper cup of the stuff and leave it, it gets so hot it will burn the cup and catch fire - done it :) ... Steve Blackmore -- It all depends on the characteristics of the resin. I import, consult and sell epoxy. I have a catalog of at least 30 different laminating resins and at least half of them are good to go for casting and doesn't produce enough heat to catch fire even in an isolated bucket. It depends on how aggressive the hardener is, Most West System that is sold is pretty fast to avoid dripping etc. And then you get heat, yes. Best regards, Sven -- October Webinars: Code for Performance Free Intel webinars can help you accelerate application performance. Explore tips for MPI, OpenMP, advanced profiling, and more. Get the most from the latest Intel processors and coprocessors. See abstracts and register http://pubads.g.doubleclick.net/gampad/clk?id=60134791iu=/4140/ostg.clktrk ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users -- October Webinars: Code for Performance Free Intel webinars can help you accelerate application performance. Explore tips for MPI, OpenMP, advanced profiling, and more. Get the most from the latest Intel processors and coprocessors. See abstracts and register http://pubads.g.doubleclick.net/gampad/clk?id=60134791iu=/4140/ostg.clktrk ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Crowbars
Maybe look into using a starter solinoid maybe 12 or 24 v I know but should handle a fair amount of current failing that could you use all three phase contacts of a three phase contactor or even four contacts if you get the spare as n/o John d norton C/o John Norton Fabs Ltd On 2 Oct 2013, at 10:54, andy pugh bodge...@gmail.com wrote: The PSU on my milling machine blew up again last night. This is the second time it has happened. I haven't pulled the box out of the machine yet, but I expect to see this again: https://picasaweb.google.com/lh/photo/xxfP_tT7Ae0op6GxUhSDvtMTjNZETYmyPJy0liipFm0?feat=directlink Which is a power resistor that has got so hot that it has exploded. (quite an odd failure mode for a resistor). The PSU is home-made and consists mainly of a bunch of capacitors and rectifier. Also in the box are two relays, two power resistors and a timer circuit. One resistor is a soft-start on the AC input side. When power is first applied the power passes through one of the resistors to limit the surge current, and then the timer closes a relay that short-out that resistor. I am fairly happy that that part of the circuit is reliable. A second relay is used in change-over mode. This has a 240V coil connected to the incoming power. When the PSU is powered up the relay closes, and supplies power to everything else inside, when the power goes off the relay opens and the NC contacts connect a crowbar resistor across the capacitors to discharge them. I think that the failure mode is that, in the case of a power glitch, the crowbar relay switches and is discharging 300V DC at a fair current, then the power returns and the NC contact tries to break 300V 10A and welds the NC contacts closed. Then the NO contacts close and we now have the crowbar resistor connected directly across the rectifier output. The crowbar resistor is not sized for continuous operation. I think that there are two problems here. If the crowbar contacts on the relay are welded shut then the power contacts should not be able to close. I think I need a more explicitly interlocked relay. Currently I am using: JG64U here: http://www.maplin.co.uk/round-base-10a-relays-2567 I think that the term I need to search for is force guided but would like some confirmation that that means what I think it means. Are contactors more dependable in this sense? The real problem is that the relay is not capable of breaking 300VDC. However, DC rated contactors are pretty expensive, and seem to jump for 220 to 44 and then 690V. I don't think I have room in the box for the big ones. I wonder if http://uk.rs-online.com/web/p/contactors/4111687/ would be OK? It really should never try to break with the capacitors charged (interlocked in HAL, which can see the DC bus voltage, and with the crowbar in circuit the voltage will drop pretty quickly anyway) My inclination is to look for a solid-state solution, but solid-state isn't very good at doing anything at all on the basis of the power going off -- atp If you can't fix it, you don't own it. http://www.ifixit.com/Manifesto -- October Webinars: Code for Performance Free Intel webinars can help you accelerate application performance. Explore tips for MPI, OpenMP, advanced profiling, and more. Get the most from the latest Intel processors and coprocessors. See abstracts and register http://pubads.g.doubleclick.net/gampad/clk?id=60134791iu=/4140/ostg.clktrk ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Crowbars
On 2 October 2013 11:09, john d norton j...@jnfabs.co.uk wrote: Maybe look into using a starter solinoid maybe 12 or 24 v I know It really needs to have interlocked NO / NC contacts and be controlled by 240V. -- atp If you can't fix it, you don't own it. http://www.ifixit.com/Manifesto -- October Webinars: Code for Performance Free Intel webinars can help you accelerate application performance. Explore tips for MPI, OpenMP, advanced profiling, and more. Get the most from the latest Intel processors and coprocessors. See abstracts and register http://pubads.g.doubleclick.net/gampad/clk?id=60134791iu=/4140/ostg.clktrk ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Crowbars
Various companies make contactors intended for DC drives. They have a conventional three-pole frame, but the center pole has NC contacts (the two outer poles have conventional NO contacts). The center pole is intended to apply a DB resistor across the motor armature after the outer poles disconnect the motor from the drive output. By design, it is impossible for the NO and NC contacts to be closed at the same time. Asea makes a whole family of them, called the EFLG series. They have permanant magnet arc blow-outs on the NC pole (hence the polarity markings on the contactor below) http://www.ebay.com/itm/230905835584 That one is from the US ebay and has a 120V coil, you might have better luck finding a 230V coil on ebay.uk. http://www.ebay.com/itm/390624331282 is another one, the coil voltage isn't specified in the auction but the full part number is, you could google for details. On Wed, Oct 2, 2013, at 08:21 AM, andy pugh wrote: On 2 October 2013 11:09, john d norton j...@jnfabs.co.uk wrote: Maybe look into using a starter solinoid maybe 12 or 24 v I know It really needs to have interlocked NO / NC contacts and be controlled by 240V. -- atp If you can't fix it, you don't own it. http://www.ifixit.com/Manifesto -- October Webinars: Code for Performance Free Intel webinars can help you accelerate application performance. Explore tips for MPI, OpenMP, advanced profiling, and more. Get the most from the latest Intel processors and coprocessors. See abstracts and register http://pubads.g.doubleclick.net/gampad/clk?id=60134791iu=/4140/ostg.clktrk ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users -- John Kasunich jmkasun...@fastmail.fm -- October Webinars: Code for Performance Free Intel webinars can help you accelerate application performance. Explore tips for MPI, OpenMP, advanced profiling, and more. Get the most from the latest Intel processors and coprocessors. See abstracts and register http://pubads.g.doubleclick.net/gampad/clk?id=60134791iu=/4140/ostg.clktrk ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Crowbars
On 2 October 2013 13:54, John Kasunich jmkasun...@fastmail.fm wrote: Various companies make contactors intended for DC drives. Ah, yes, that looks approximately perfect apart from the cost and the delivery time. (I can't see any on eBay UK) I have ordered the 220VDC rated contactor from RS, however, as I wanted a quick solution. -- atp If you can't fix it, you don't own it. http://www.ifixit.com/Manifesto -- October Webinars: Code for Performance Free Intel webinars can help you accelerate application performance. Explore tips for MPI, OpenMP, advanced profiling, and more. Get the most from the latest Intel processors and coprocessors. See abstracts and register http://pubads.g.doubleclick.net/gampad/clk?id=60134791iu=/4140/ostg.clktrk ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Crowbars
The relay or contactor you use must be a break before make style. I like contactors better as the distance between contacts tends to be larger, so more time between break make. A larger value resistor for bleed off might be in order. I usually put a very large value resistor across the power supply. You waste some power, but you always know the supply has been bled off before poking into it. --J. Ray Mitchell Jr. jrmitche...@gmail.com (818)324-7573 “Truth is treason in the Empire of Lies.” — Ron Paul On Wed, Oct 2, 2013 at 6:12 AM, andy pugh bodge...@gmail.com wrote: On 2 October 2013 13:54, John Kasunich jmkasun...@fastmail.fm wrote: Various companies make contactors intended for DC drives. Ah, yes, that looks approximately perfect apart from the cost and the delivery time. (I can't see any on eBay UK) I have ordered the 220VDC rated contactor from RS, however, as I wanted a quick solution. -- atp If you can't fix it, you don't own it. http://www.ifixit.com/Manifesto -- October Webinars: Code for Performance Free Intel webinars can help you accelerate application performance. Explore tips for MPI, OpenMP, advanced profiling, and more. Get the most from the latest Intel processors and coprocessors. See abstracts and register http://pubads.g.doubleclick.net/gampad/clk?id=60134791iu=/4140/ostg.clktrk ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users -- October Webinars: Code for Performance Free Intel webinars can help you accelerate application performance. Explore tips for MPI, OpenMP, advanced profiling, and more. Get the most from the latest Intel processors and coprocessors. See abstracts and register http://pubads.g.doubleclick.net/gampad/clk?id=60134791iu=/4140/ostg.clktrk ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Crowbars
Contactors are generally a lot more robust than relays. Since switching to contactors on my supplies I have never had any welded contact issues. I normally switch the AC before the rectifier instead of the DC. This does mean the smoothing caps are permanently connected to the load but in my opinion this is a good thing for two reasons. First the caps help absorb the reverse energy dump from stopping the motors quickly. Secondly in my experience having the DC bus live for a fraction of a second after ESTOP helps stop motion quickly. Instead of simply letting the motors free wheel the drives will actively try to stop motion until the supply dies. Les On 02/10/2013 10:54, andy pugh wrote: The PSU on my milling machine blew up again last night. This is the second time it has happened. I haven't pulled the box out of the machine yet, but I expect to see this again: https://picasaweb.google.com/lh/photo/xxfP_tT7Ae0op6GxUhSDvtMTjNZETYmyPJy0liipFm0?feat=directlink Which is a power resistor that has got so hot that it has exploded. (quite an odd failure mode for a resistor). The PSU is home-made and consists mainly of a bunch of capacitors and rectifier. Also in the box are two relays, two power resistors and a timer circuit. One resistor is a soft-start on the AC input side. When power is first applied the power passes through one of the resistors to limit the surge current, and then the timer closes a relay that short-out that resistor. I am fairly happy that that part of the circuit is reliable. A second relay is used in change-over mode. This has a 240V coil connected to the incoming power. When the PSU is powered up the relay closes, and supplies power to everything else inside, when the power goes off the relay opens and the NC contacts connect a crowbar resistor across the capacitors to discharge them. I think that the failure mode is that, in the case of a power glitch, the crowbar relay switches and is discharging 300V DC at a fair current, then the power returns and the NC contact tries to break 300V 10A and welds the NC contacts closed. Then the NO contacts close and we now have the crowbar resistor connected directly across the rectifier output. The crowbar resistor is not sized for continuous operation. I think that there are two problems here. If the crowbar contacts on the relay are welded shut then the power contacts should not be able to close. I think I need a more explicitly interlocked relay. Currently I am using: JG64U here: http://www.maplin.co.uk/round-base-10a-relays-2567 I think that the term I need to search for is force guided but would like some confirmation that that means what I think it means. Are contactors more dependable in this sense? The real problem is that the relay is not capable of breaking 300VDC. However, DC rated contactors are pretty expensive, and seem to jump for 220 to 44 and then 690V. I don't think I have room in the box for the big ones. I wonder if http://uk.rs-online.com/web/p/contactors/4111687/ would be OK? It really should never try to break with the capacitors charged (interlocked in HAL, which can see the DC bus voltage, and with the crowbar in circuit the voltage will drop pretty quickly anyway) My inclination is to look for a solid-state solution, but solid-state isn't very good at doing anything at all on the basis of the power going off -- October Webinars: Code for Performance Free Intel webinars can help you accelerate application performance. Explore tips for MPI, OpenMP, advanced profiling, and more. Get the most from the latest Intel processors and coprocessors. See abstracts and register http://pubads.g.doubleclick.net/gampad/clk?id=60134791iu=/4140/ostg.clktrk ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Crowbars
On 2 October 2013 14:55, jrmitchellj . jrmitche...@gmail.com wrote: The relay or contactor you use must be a break before make style The ones I have been using are meant to be, but they are not force-guided to ensure it. A larger value resistor for bleed off might be in order. I usually put a very large value resistor across the power supply. You waste some power, but you always know the supply has been bled off before poking into it. Do you mean very large in the physical sense or the value sense? I have 20,000uF of caps at 300V. For a 100W resistor to be happy steady-state then the minimum resistance it can have is about 1k. That will take 82 seconds to drop the voltage to 5V, which is longer than I would like. I guess I could use a 250W resistor, which is 30s to 5V, or a 1kW resistor, which is 7.5 seconds to 5V. But both seem wasteful, and I am not sure I have the space. (Also quite expensive: http://uk.rs-online.com/web/p/panel-mount-fixed-resistors/7014059/ ) Currently the 50R 100W resistor which is switched-in only when needed takes 5 seconds to drop the voltage to comfortable levels. And it doesn't even get warm in that time. (unless, as has been discovered, the relay that switches it in manages to weld shut and keep it in circuit at the same time as the mains supply is connected) -- atp If you can't fix it, you don't own it. http://www.ifixit.com/Manifesto -- October Webinars: Code for Performance Free Intel webinars can help you accelerate application performance. Explore tips for MPI, OpenMP, advanced profiling, and more. Get the most from the latest Intel processors and coprocessors. See abstracts and register http://pubads.g.doubleclick.net/gampad/clk?id=60134791iu=/4140/ostg.clktrk ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Crowbars
Large in value sense. --J. Ray Mitchell Jr. jrmitche...@gmail.com (818)324-7573 “Truth is treason in the Empire of Lies.” — Ron Paul On Wed, Oct 2, 2013 at 7:47 AM, andy pugh bodge...@gmail.com wrote: On 2 October 2013 14:55, jrmitchellj . jrmitche...@gmail.com wrote: The relay or contactor you use must be a break before make style The ones I have been using are meant to be, but they are not force-guided to ensure it. A larger value resistor for bleed off might be in order. I usually put a very large value resistor across the power supply. You waste some power, but you always know the supply has been bled off before poking into it. Do you mean very large in the physical sense or the value sense? I have 20,000uF of caps at 300V. For a 100W resistor to be happy steady-state then the minimum resistance it can have is about 1k. That will take 82 seconds to drop the voltage to 5V, which is longer than I would like. I guess I could use a 250W resistor, which is 30s to 5V, or a 1kW resistor, which is 7.5 seconds to 5V. But both seem wasteful, and I am not sure I have the space. (Also quite expensive: http://uk.rs-online.com/web/p/panel-mount-fixed-resistors/7014059/ ) Currently the 50R 100W resistor which is switched-in only when needed takes 5 seconds to drop the voltage to comfortable levels. And it doesn't even get warm in that time. (unless, as has been discovered, the relay that switches it in manages to weld shut and keep it in circuit at the same time as the mains supply is connected) -- atp If you can't fix it, you don't own it. http://www.ifixit.com/Manifesto -- October Webinars: Code for Performance Free Intel webinars can help you accelerate application performance. Explore tips for MPI, OpenMP, advanced profiling, and more. Get the most from the latest Intel processors and coprocessors. See abstracts and register http://pubads.g.doubleclick.net/gampad/clk?id=60134791iu=/4140/ostg.clktrk ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users -- October Webinars: Code for Performance Free Intel webinars can help you accelerate application performance. Explore tips for MPI, OpenMP, advanced profiling, and more. Get the most from the latest Intel processors and coprocessors. See abstracts and register http://pubads.g.doubleclick.net/gampad/clk?id=60134791iu=/4140/ostg.clktrk ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Crowbars
On 2 October 2013 16:00, jrmitchellj . jrmitche...@gmail.com wrote: Large in value sense. The problem here is that my capacitors are large (in both senses) and so a large value resistor will take a long time to discharge the caps. -- atp If you can't fix it, you don't own it. http://www.ifixit.com/Manifesto -- October Webinars: Code for Performance Free Intel webinars can help you accelerate application performance. Explore tips for MPI, OpenMP, advanced profiling, and more. Get the most from the latest Intel processors and coprocessors. See abstracts and register http://pubads.g.doubleclick.net/gampad/clk?id=60134791iu=/4140/ostg.clktrk ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Crowbars
On Wed, Oct 2, 2013, at 10:47 AM, andy pugh wrote: I guess I could use a 250W resistor, which is 30s to 5V, or a 1kW resistor, which is 7.5 seconds to 5V. But both seem wasteful, and I am not sure I have the space. (Also quite expensive: http://uk.rs-online.com/web/p/panel-mount-fixed-resistors/7014059/ ) For intermittent duty (as you are using it - connected only on power down), the cheapest high-power resistors are heaters. For example: $8 gets you 38.4 ohms, 1500W intermittent (or continuous, if wet ;-): http://www.ebay.com/itm/200960173435 That has more then enough thermal mass to handle 20,000uF at 300V. I've used 2 of those in series to discharge 24,000uF at 600V (4.8 times the energy). The flange makes it fairly easy to mount. $13 gets the same ohms and watts, but can run continuously if needed: http://www.ebay.com/itm/131001379245 Just don't put anything meltable nearby. I've seen these used as DB resistors for spindle drives - mounted in a mesh box on top of the machine so the heat can escape. -- John Kasunich jmkasun...@fastmail.fm -- October Webinars: Code for Performance Free Intel webinars can help you accelerate application performance. Explore tips for MPI, OpenMP, advanced profiling, and more. Get the most from the latest Intel processors and coprocessors. See abstracts and register http://pubads.g.doubleclick.net/gampad/clk?id=60134791iu=/4140/ostg.clktrk ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
[Emc-users] Following Error with Steppers
I'm getting joint following errors on my Z-Axis when I increase the jog speed above ~1015 mm/min. I also see it on X (and presumably Y) when I increase its max speed to over 2336 mm/min; not quite linear given Z has twice (4mm/rev) the pitch of X (2mm/rev) with the same microstepping (800/rev). BTW: I don't use 2336 mm/min in real life (ACME lead screws :-(); I'm just playing with the jog button in Axis with the drivers powered down but the Z axis will certainly do a bit more than 1015 mm/min and I'd like to use that or at least understand why I can't. It's a stepper based system using a Mesa 5I25 and the standard BASE_PERIOD of 50us which should allow 20,000 steps per second (according to TFM). The SERVO_PERIOD is 100 (standard). 1015 mm/min is 17 mm/s and my Z STEP_SCALE is set at 200 (4mm pitch, 800 microsteps per rev) so that's 17*200 = 3,400 steps per second which is well within the 20,000. I've tried increasing FERROR to silly levels (10), deleting MIN_FERROR and that doesn't seem to make much difference. The thing that did make a difference was decreasing the MAX_ACCELERATION to something really slow like 5mm/s/s, it's normally set at 350, but playing in pncconf I can get over 40 mm/s with an acceleration of 350 mm/s/s so I don't understand what's going wrong. I'm obviously being a muppet (what's new?) and misunderstanding something here. Could one of you gurus help shine some light on this? -- Regards, Russell | Russell Brown | MAIL: russ...@lls.com PHONE: 01780 471800 | | Lady Lodge Systems | WWW Work: http://www.lls.com | | Peterborough, England | WWW Play: http://www.ruffle.me.uk | -- October Webinars: Code for Performance Free Intel webinars can help you accelerate application performance. Explore tips for MPI, OpenMP, advanced profiling, and more. Get the most from the latest Intel processors and coprocessors. See abstracts and register http://pubads.g.doubleclick.net/gampad/clk?id=60134791iu=/4140/ostg.clktrk ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Following Error with Steppers
On Wed, 2 Oct 2013, Russell Brown wrote: Date: Wed, 2 Oct 2013 17:08:50 +0100 (BST) From: Russell Brown russ...@lls.lls.com Reply-To: Enhanced Machine Controller (EMC) emc-users@lists.sourceforge.net To: emc-users@lists.sourceforge.net Subject: [Emc-users] Following Error with Steppers I'm getting joint following errors on my Z-Axis when I increase the jog speed above ~1015 mm/min. I also see it on X (and presumably Y) when I increase its max speed to over 2336 mm/min; not quite linear given Z has twice (4mm/rev) the pitch of X (2mm/rev) with the same microstepping (800/rev). BTW: I don't use 2336 mm/min in real life (ACME lead screws :-(); I'm just playing with the jog button in Axis with the drivers powered down but the Z axis will certainly do a bit more than 1015 mm/min and I'd like to use that or at least understand why I can't. It's a stepper based system using a Mesa 5I25 and the standard BASE_PERIOD of 50us which should allow 20,000 steps per second (according to TFM). The SERVO_PERIOD is 100 (standard). There should be no base thread at all with hardware stepgens (it will make things worse and may even be the cause of the following error) 1015 mm/min is 17 mm/s and my Z STEP_SCALE is set at 200 (4mm pitch, 800 microsteps per rev) so that's 17*200 = 3,400 steps per second which is well within the 20,000. I've tried increasing FERROR to silly levels (10), deleting MIN_FERROR and that doesn't seem to make much difference. The thing that did make a difference was decreasing the MAX_ACCELERATION to something really slow like 5mm/s/s, it's normally set at 350, but playing in pncconf I can get over 40 mm/s with an acceleration of 350 mm/s/s so I don't understand what's going wrong. I'm obviously being a muppet (what's new?) and misunderstanding something here. Could one of you gurus help shine some light on this? One thing that is required is that the per axis stepgen maxaccel parameter be set to about 20% greater than the machine maxaccel for that axis. -- Regards, Russell | Russell Brown | MAIL: russ...@lls.com PHONE: 01780 471800 | | Lady Lodge Systems | WWW Work: http://www.lls.com | | Peterborough, England | WWW Play: http://www.ruffle.me.uk | -- October Webinars: Code for Performance Free Intel webinars can help you accelerate application performance. Explore tips for MPI, OpenMP, advanced profiling, and more. Get the most from the latest Intel processors and coprocessors. See abstracts and register http://pubads.g.doubleclick.net/gampad/clk?id=60134791iu=/4140/ostg.clktrk ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users Peter Wallace Mesa Electronics (\__/) (='.'=) This is Bunny. Copy and paste bunny into your ()_() signature to help him gain world domination. -- October Webinars: Code for Performance Free Intel webinars can help you accelerate application performance. Explore tips for MPI, OpenMP, advanced profiling, and more. Get the most from the latest Intel processors and coprocessors. See abstracts and register http://pubads.g.doubleclick.net/gampad/clk?id=60134791iu=/4140/ostg.clktrk ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Crowbars
Quoth John Kasunich. $13 gets the same ohms and watts, but can run continuously if needed: http://www.ebay.com/itm/131001379245 That's brilliant... stick a kettle on top and Andy automatically gets a nice cuppa when he's finished making chips :-) -- Regards, Russell | Russell Brown | MAIL: russ...@lls.com PHONE: 01780 471800 | | Lady Lodge Systems | WWW Work: http://www.lls.com | | Peterborough, England | WWW Play: http://www.ruffle.me.uk | -- October Webinars: Code for Performance Free Intel webinars can help you accelerate application performance. Explore tips for MPI, OpenMP, advanced profiling, and more. Get the most from the latest Intel processors and coprocessors. See abstracts and register http://pubads.g.doubleclick.net/gampad/clk?id=60134791iu=/4140/ostg.clktrk ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Crowbars
Andy, I think you need to add a sealed in relay on your input power contactor circuit. You start the machine by pushing a power on button which has a seal in contact to hold the contactor in place after the button is released. When the power drops out the contactor drops out and will not pull back in when the power recovers unless you push the power on button.To make it even safer, you can add an auxiliary contact off the crowbar relay such that if the crowbar relay is stuck on, the start circuit will not function ( a NC axillary contact off the crowbar contactor should work). I'd stick all of this into a metal box just in case something catches on fire.. the box should contain the flames. Contactors are typically much more robust than relays. Regarding DC vs AC contactors, I would use a regular AC contactor for the crowbar contactor. DC contactors are specialized in that they can break DC current which is difficult to do. You don't need to break DC current, you need to conduct DC current.. a different problem that should cause little to no arcing.Just interlock the crowbar contactor with the infeed contactor so that if the crowbar contactor fails stuck on, you don't drive power supply current into the resistor. Over here (in the USA) we have cheap Fuji contactors available from Automation Direct. I'd find out who sells them in the UK.A 25 amp IEC contactor with a 24 vdc coil is about $40.00 US. http://www.automationdirect.com/adc/Shopping/Catalog/Motor_Controls/Fuji_Contactors_-z-_Overloads/9_to_25_Amp I have used hundreds of them and they seem to be very durable. It looks like http://www.lamonde.com/ sells Automation Direct equipment in the UK but I don't see Fuji Contactors in the list of items sold. Dave On 10/2/2013 5:54 AM, andy pugh wrote: The PSU on my milling machine blew up again last night. This is the second time it has happened. I haven't pulled the box out of the machine yet, but I expect to see this again: https://picasaweb.google.com/lh/photo/xxfP_tT7Ae0op6GxUhSDvtMTjNZETYmyPJy0liipFm0?feat=directlink Which is a power resistor that has got so hot that it has exploded. (quite an odd failure mode for a resistor). The PSU is home-made and consists mainly of a bunch of capacitors and rectifier. Also in the box are two relays, two power resistors and a timer circuit. One resistor is a soft-start on the AC input side. When power is first applied the power passes through one of the resistors to limit the surge current, and then the timer closes a relay that short-out that resistor. I am fairly happy that that part of the circuit is reliable. A second relay is used in change-over mode. This has a 240V coil connected to the incoming power. When the PSU is powered up the relay closes, and supplies power to everything else inside, when the power goes off the relay opens and the NC contacts connect a crowbar resistor across the capacitors to discharge them. I think that the failure mode is that, in the case of a power glitch, the crowbar relay switches and is discharging 300V DC at a fair current, then the power returns and the NC contact tries to break 300V 10A and welds the NC contacts closed. Then the NO contacts close and we now have the crowbar resistor connected directly across the rectifier output. The crowbar resistor is not sized for continuous operation. I think that there are two problems here. If the crowbar contacts on the relay are welded shut then the power contacts should not be able to close. I think I need a more explicitly interlocked relay. Currently I am using: JG64U here: http://www.maplin.co.uk/round-base-10a-relays-2567 I think that the term I need to search for is force guided but would like some confirmation that that means what I think it means. Are contactors more dependable in this sense? The real problem is that the relay is not capable of breaking 300VDC. However, DC rated contactors are pretty expensive, and seem to jump for 220 to 44 and then 690V. I don't think I have room in the box for the big ones. I wonder if http://uk.rs-online.com/web/p/contactors/4111687/ would be OK? It really should never try to break with the capacitors charged (interlocked in HAL, which can see the DC bus voltage, and with the crowbar in circuit the voltage will drop pretty quickly anyway) My inclination is to look for a solid-state solution, but solid-state isn't very good at doing anything at all on the basis of the power going off -- October Webinars: Code for Performance Free Intel webinars can help you accelerate application performance. Explore tips for MPI, OpenMP, advanced profiling, and more. Get the most from the latest Intel processors and coprocessors. See abstracts and register http://pubads.g.doubleclick.net/gampad/clk?id=60134791iu=/4140/ostg.clktrk
Re: [Emc-users] Crowbars
On 2 October 2013 17:33, Dave Cole linuxcncro...@gmail.com wrote: When the power drops out the contactor drops out and will not pull back in when the power recovers unless you push the power on button. I think I am happy to trust this to HAL. I may add an input to HAL from the contactor discharging mode active and interlock that to the DC bus voltage so that I can't re-energise the PSU until the caps are down below a few volts. (There is a separate LinuxCNC-controlled contactor that powers up all the AC loads, servo PSU, VFD, Ikea LED lights…) -- atp If you can't fix it, you don't own it. http://www.ifixit.com/Manifesto -- October Webinars: Code for Performance Free Intel webinars can help you accelerate application performance. Explore tips for MPI, OpenMP, advanced profiling, and more. Get the most from the latest Intel processors and coprocessors. See abstracts and register http://pubads.g.doubleclick.net/gampad/clk?id=60134791iu=/4140/ostg.clktrk ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Following Error with Steppers
Quoth Peter C. Wallace. On Wed, 2 Oct 2013, Russell Brown wrote: It's a stepper based system using a Mesa 5I25 and the standard BASE_PERIOD of 50us which should allow 20,000 steps per second (according to TFM). There should be no base thread at all with hardware stepgens (it will make things worse and may even be the cause of the following error) The original config from pncconf didn't have the BASE_PERIOD in the .ini file. I did put one in during my flailing around but I've just taken it out and there's no difference. However, it looks like my .hal file (pncconf generated) doesn't use it anyway:- Mesa_Mill.hal:loadrt [EMCMOT]EMCMOT servo_period_nsec=[EMCMOT]SERVO_PERIOD num_joints=[TRAJ]AXES and talking of the .hal file, the only thing that's changed from the pncconf generated version is AFAIR that I had to comment out the following two lines: loadrt abs names= loadrt lowpass names= as linuxcnc won't start with them in the file. One thing that is required is that the per axis stepgen maxaccel parameter be set to about 20% greater than the machine maxaccel for that axis. I did have it set to double (700). Just tried 420 (350 * 1.2). No difference :-( FWIW, I've stuck my .ini and .hal files here: http://ruffle.me.uk/cnc/Mesa_Mill.ini http://ruffle.me.uk/cnc/Mesa_Mill.hal if anyone's kind enough to have a quick gander and tell me what stupid mistake I've made I'd be very grateful. -- Regards, Russell | Russell Brown | MAIL: russ...@lls.com PHONE: 01780 471800 | | Lady Lodge Systems | WWW Work: http://www.lls.com | | Peterborough, England | WWW Play: http://www.ruffle.me.uk | -- October Webinars: Code for Performance Free Intel webinars can help you accelerate application performance. Explore tips for MPI, OpenMP, advanced profiling, and more. Get the most from the latest Intel processors and coprocessors. See abstracts and register http://pubads.g.doubleclick.net/gampad/clk?id=60134791iu=/4140/ostg.clktrk ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Crowbars
andy pugh wrote: I think that the failure mode is that, in the case of a power glitch, the crowbar relay switches and is discharging 300V DC at a fair current, then the power returns and the NC contact tries to break 300V 10A and welds the NC contacts closed. Then the NO contacts close and we now have the crowbar resistor connected directly across the rectifier output. The crowbar resistor is not sized for continuous operation. If this is the case, the contacts will still be welded, so open up the relay and examine it. Normal relays are severely derated for DC, and breaking 300 V DC cannot be accomplished by any standard relay. It probably doesn't take a glitch on the mains, just after so many on/off cycles, you will get a failure as the contacts degrade. One way to solve the fire problem is to put a fuse (correctly rated for 300 V DC) in series with the source, and strap it to the resistor. When the resistor overheats, it will melt the fuse. But, that will be a safety hack, rather than a fix. Use double-break contactors with large contact spacing for 600 V+, or use a FET to control the dump resistor. Jon -- October Webinars: Code for Performance Free Intel webinars can help you accelerate application performance. Explore tips for MPI, OpenMP, advanced profiling, and more. Get the most from the latest Intel processors and coprocessors. See abstracts and register http://pubads.g.doubleclick.net/gampad/clk?id=60134791iu=/4140/ostg.clktrk ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Following Error with Steppers
You might post this on the forum in the pncconf section, it does sound like a little bug with pncconf. Is this a 5i25/7i76 combo? You might just try a plain config that is known to work... http://gnipsel.com/linuxcnc/configs/index.html JT On 10/2/2013 12:26 PM, Russell Brown wrote: Quoth Peter C. Wallace. On Wed, 2 Oct 2013, Russell Brown wrote: It's a stepper based system using a Mesa 5I25 and the standard BASE_PERIOD of 50us which should allow 20,000 steps per second (according to TFM). There should be no base thread at all with hardware stepgens (it will make things worse and may even be the cause of the following error) The original config from pncconf didn't have the BASE_PERIOD in the .ini file. I did put one in during my flailing around but I've just taken it out and there's no difference. However, it looks like my .hal file (pncconf generated) doesn't use it anyway:- Mesa_Mill.hal:loadrt [EMCMOT]EMCMOT servo_period_nsec=[EMCMOT]SERVO_PERIOD num_joints=[TRAJ]AXES and talking of the .hal file, the only thing that's changed from the pncconf generated version is AFAIR that I had to comment out the following two lines: loadrt abs names= loadrt lowpass names= as linuxcnc won't start with them in the file. One thing that is required is that the per axis stepgen maxaccel parameter be set to about 20% greater than the machine maxaccel for that axis. I did have it set to double (700). Just tried 420 (350 * 1.2). No difference :-( FWIW, I've stuck my .ini and .hal files here: http://ruffle.me.uk/cnc/Mesa_Mill.ini http://ruffle.me.uk/cnc/Mesa_Mill.hal if anyone's kind enough to have a quick gander and tell me what stupid mistake I've made I'd be very grateful. -- October Webinars: Code for Performance Free Intel webinars can help you accelerate application performance. Explore tips for MPI, OpenMP, advanced profiling, and more. Get the most from the latest Intel processors and coprocessors. See abstracts and register http://pubads.g.doubleclick.net/gampad/clk?id=60134791iu=/4140/ostg.clktrk ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
[Emc-users] CNC meeting near Chicago
In case people don't know, there will be a CNC-related meeting October 5th (Saturday) in Wheaton, IL. Contact saku...@gmail.com for more info, or check http://www.osmoces.org/ It is at the IIT Rice campus. I'll be there representing LinuxCNC, and bring along my minimill to demo. I will give a talk about history and capabilities of LinuxCNC at 10:30 AM, but will have the mill set up all day. Jon -- October Webinars: Code for Performance Free Intel webinars can help you accelerate application performance. Explore tips for MPI, OpenMP, advanced profiling, and more. Get the most from the latest Intel processors and coprocessors. See abstracts and register http://pubads.g.doubleclick.net/gampad/clk?id=60134791iu=/4140/ostg.clktrk ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Following Error with Steppers
On 2 October 2013 18:26, Russell Brown russ...@lls.lls.com wrote: loadrt abs names= loadrt lowpass names= This is a stepfconf bug. I can't recall what prompts it. I thought it was fixed. (it tries to load a bunch of components with blank names, and then their pin names collide) http://ruffle.me.uk/cnc/Mesa_Mill.ini http://ruffle.me.uk/cnc/Mesa_Mill.hal The INI file Z axis max velocity in the INI is a lot higher than the stepgen max velocity in the HAL file. Also, the HAL file is not actually looking in the INI file for the stepgen maxaccel, so ini file settings are not having any effect. (Which version of PNCconf is this? It is making a lot of mistakes). If you look in the HAL file both stepgen accel and velocity are absolute values rather than being sucked out of the INI file. -- atp If you can't fix it, you don't own it. http://www.ifixit.com/Manifesto -- October Webinars: Code for Performance Free Intel webinars can help you accelerate application performance. Explore tips for MPI, OpenMP, advanced profiling, and more. Get the most from the latest Intel processors and coprocessors. See abstracts and register http://pubads.g.doubleclick.net/gampad/clk?id=60134791iu=/4140/ostg.clktrk ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
[Emc-users] Highz-720 with Zero3 controller
I have a Highz-720 CNC machine from Heiz in Germany . I cant get EMC to work with it.I run Linux-CNC 2.4.6 I also have another CNC machine for which EMC works perfectly! Any suggestions? Anyone else has this combination? Rindert Schutten Designer/Owner SchuttenWorks Find us on the Web at http://schuttenworks.com Like us on Facebook at https://www.facebook.com/schuttenworks - -- October Webinars: Code for Performance Free Intel webinars can help you accelerate application performance. Explore tips for MPI, OpenMP, advanced profiling, and more. Get the most from the latest Intel processors and coprocessors. See abstracts and register http://pubads.g.doubleclick.net/gampad/clk?id=60134791iu=/4140/ostg.clktrk ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Crowbars
On 2 October 2013 18:28, Jon Elson el...@pico-systems.com wrote: If this is the case, the contacts will still be welded, so open up the relay and examine it. I will, but as I still have the welded relay from last time, I think I know that it can happen. Normal relays are severely derated for DC, and breaking 300 V DC cannot be accomplished by any standard relay. It probably doesn't take a glitch on the mains, just after so many on/off cycles, you will get a failure as the contacts degrade. The relay should never even try to _break_ 300V DC. It _makes_ 300V DC to discharge the caps, but should only ever break when the caps are at 0V. or use a FET to control the dump resistor. I would like to do this, but I am not sure how to wire a FET to discharge the cap when AC power is removed (Whereas an NC relay does this easily) I though of using the fact that Thyristors latch on when current is flowing, but then I think I run the risk of restoring AC power while the device is still conducting, with the same result. -- atp If you can't fix it, you don't own it. http://www.ifixit.com/Manifesto -- October Webinars: Code for Performance Free Intel webinars can help you accelerate application performance. Explore tips for MPI, OpenMP, advanced profiling, and more. Get the most from the latest Intel processors and coprocessors. See abstracts and register http://pubads.g.doubleclick.net/gampad/clk?id=60134791iu=/4140/ostg.clktrk ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Crowbars
On Wed, Oct 2, 2013, at 01:58 PM, andy pugh wrote: On 2 October 2013 18:28, Jon Elson el...@pico-systems.com wrote: or use a FET to control the dump resistor. I would like to do this, but I am not sure how to wire a FET to discharge the cap when AC power is removed (Whereas an NC relay does this easily) One way to use a FET (or IGBT) for this: Put a 12 to 15V zener diode from gate to source. Put a resistor from gate to drain. The resistor should be chosen to deliver 10-20mA. For 300V, that means 15-30K. It will dissipate 3-6 watts, so size it conservatively. Connect a low power relay such that when power is on it shorts the gate to the source, turning the FET off. When the power goes off, the relay opens, and the 10mA current charges the gate until the zener clamps it. That turns the FET on. Once the bus discharges below 12V the gate voltage will droop, but at that point you don't care. Note that just like the relay, the FET can fail in the ON position, applying steady state power to your bleeder resistor. In one project I worked on, we used the water heater elements and mounted a small bi-metal snap-disk thermostat to the element. If the element overheats because of continuous power, the thermostat opens and kills main power by turning off the main contactor. -- John Kasunich jmkasun...@fastmail.fm -- October Webinars: Code for Performance Free Intel webinars can help you accelerate application performance. Explore tips for MPI, OpenMP, advanced profiling, and more. Get the most from the latest Intel processors and coprocessors. See abstracts and register http://pubads.g.doubleclick.net/gampad/clk?id=60134791iu=/4140/ostg.clktrk ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Crowbars
That could work as well. I thought this was part of your safety circuit to bring the power supply voltage down to zero ASAP. As in the motor is running away and I need to kill the drive. Dave On 10/2/2013 1:11 PM, andy pugh wrote: On 2 October 2013 17:33, Dave Cole linuxcncro...@gmail.com wrote: When the power drops out the contactor drops out and will not pull back in when the power recovers unless you push the power on button. I think I am happy to trust this to HAL. I may add an input to HAL from the contactor discharging mode active and interlock that to the DC bus voltage so that I can't re-energise the PSU until the caps are down below a few volts. (There is a separate LinuxCNC-controlled contactor that powers up all the AC loads, servo PSU, VFD, Ikea LED lights…) -- October Webinars: Code for Performance Free Intel webinars can help you accelerate application performance. Explore tips for MPI, OpenMP, advanced profiling, and more. Get the most from the latest Intel processors and coprocessors. See abstracts and register http://pubads.g.doubleclick.net/gampad/clk?id=60134791iu=/4140/ostg.clktrk ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Crowbars
Just wire the relay to the AC line. Connect the resistor to the COM NC contacts. Relay connects bleeder resistors when AC line is removed. No need to get fancy. Stephen On Wed, Oct 2, 2013 at 2:43 PM, Dave Cole linuxcncro...@gmail.com wrote: That could work as well. I thought this was part of your safety circuit to bring the power supply voltage down to zero ASAP. As in the motor is running away and I need to kill the drive. Dave On 10/2/2013 1:11 PM, andy pugh wrote: On 2 October 2013 17:33, Dave Cole linuxcncro...@gmail.com wrote: When the power drops out the contactor drops out and will not pull back in when the power recovers unless you push the power on button. I think I am happy to trust this to HAL. I may add an input to HAL from the contactor discharging mode active and interlock that to the DC bus voltage so that I can't re-energise the PSU until the caps are down below a few volts. (There is a separate LinuxCNC-controlled contactor that powers up all the AC loads, servo PSU, VFD, Ikea LED lights…) -- October Webinars: Code for Performance Free Intel webinars can help you accelerate application performance. Explore tips for MPI, OpenMP, advanced profiling, and more. Get the most from the latest Intel processors and coprocessors. See abstracts and register http://pubads.g.doubleclick.net/gampad/clk?id=60134791iu=/4140/ostg.clktrk ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users -- October Webinars: Code for Performance Free Intel webinars can help you accelerate application performance. Explore tips for MPI, OpenMP, advanced profiling, and more. Get the most from the latest Intel processors and coprocessors. See abstracts and register http://pubads.g.doubleclick.net/gampad/clk?id=60134791iu=/4140/ostg.clktrk ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Crowbars
On 2 October 2013 20:41, Stephen Dubovsky smdubov...@gmail.com wrote: Just wire the relay to the AC line. Connect the resistor to the COM NC contacts. Relay connects bleeder resistors when AC line is removed. No need to get fancy. That was what I thought. https://plus.google.com/photos/108164504656404380542/albums/5930254306221907233 Has twice been the result. The problem comes when the relay attempts to open for whatever reason while the caps are not fully discharged. (such as a momentary power glitch) However, there is a similar problem using a solid-state solution, as exactly the same thing will happen if the FET is latched on. -- atp If you can't fix it, you don't own it. http://www.ifixit.com/Manifesto -- October Webinars: Code for Performance Free Intel webinars can help you accelerate application performance. Explore tips for MPI, OpenMP, advanced profiling, and more. Get the most from the latest Intel processors and coprocessors. See abstracts and register http://pubads.g.doubleclick.net/gampad/clk?id=60134791iu=/4140/ostg.clktrk ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
[Emc-users] What does these do?
Power up brakes? There were nine of these at the power source side in the mill I am retrofitting. They are grouped in three. I guess they have something to do with the power-on process. Or energy dumping when stopping the spindle. On top of that I have no idea why they are connected like this. Please enlighten me! Sven -- October Webinars: Code for Performance Free Intel webinars can help you accelerate application performance. Explore tips for MPI, OpenMP, advanced profiling, and more. Get the most from the latest Intel processors and coprocessors. See abstracts and register http://pubads.g.doubleclick.net/gampad/clk?id=60134791iu=/4140/ostg.clktrk ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] What does these do?
2013/10/3 Sven Wesley svenne.d...@gmail.com Power up brakes? There were nine of these at the power source side in the mill I am retrofitting. They are grouped in three. I guess they have something to do with the power-on process. Or energy dumping when stopping the spindle. On top of that I have no idea why they are connected like this. Please enlighten me! Sven Would be so much easier if I added the images... http://farm8.staticflickr.com/7454/10060787165_14d7c48292_b.jpg http://farm8.staticflickr.com/7343/10060783435_454908a156_b.jpg -- October Webinars: Code for Performance Free Intel webinars can help you accelerate application performance. Explore tips for MPI, OpenMP, advanced profiling, and more. Get the most from the latest Intel processors and coprocessors. See abstracts and register http://pubads.g.doubleclick.net/gampad/clk?id=60134791iu=/4140/ostg.clktrk ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] What does these do?
Probably braking resistors for the spindle. The resistors are connected across the 3 phases of the motor to bring the motor to a rapid stop. Looks like they are wired in a Wye or Star connection..One center connection and the three phases which probably connect to a contactor which is connected across the motor during rapid braking. Dave On 10/2/2013 7:47 PM, Sven Wesley wrote: 2013/10/3 Sven Wesley svenne.d...@gmail.com Power up brakes? There were nine of these at the power source side in the mill I am retrofitting. They are grouped in three. I guess they have something to do with the power-on process. Or energy dumping when stopping the spindle. On top of that I have no idea why they are connected like this. Please enlighten me! Sven Would be so much easier if I added the images... http://farm8.staticflickr.com/7454/10060787165_14d7c48292_b.jpg http://farm8.staticflickr.com/7343/10060783435_454908a156_b.jpg -- October Webinars: Code for Performance Free Intel webinars can help you accelerate application performance. Explore tips for MPI, OpenMP, advanced profiling, and more. Get the most from the latest Intel processors and coprocessors. See abstracts and register http://pubads.g.doubleclick.net/gampad/clk?id=60134791iu=/4140/ostg.clktrk ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users -- October Webinars: Code for Performance Free Intel webinars can help you accelerate application performance. Explore tips for MPI, OpenMP, advanced profiling, and more. Get the most from the latest Intel processors and coprocessors. See abstracts and register http://pubads.g.doubleclick.net/gampad/clk?id=60134791iu=/4140/ostg.clktrk ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Following Error with Steppers
From: bodge...@gmail.com Date: Wed, 2 Oct 2013 18:47:08 +0100 To: emc-users@lists.sourceforge.net Subject: Re: [Emc-users] Following Error with Steppers On 2 October 2013 18:26, Russell Brown russ...@lls.lls.com wrote: loadrt abs names= loadrt lowpass names= This is a stepfconf bug. I can't recall what prompts it. I thought it was fixed. (it tries to load a bunch of components with blank names, and then their pin names collide) Pncconf bug -but is probably fixed. what version was this made with? http://ruffle.me.uk/cnc/Mesa_Mill.ini http://ruffle.me.uk/cnc/Mesa_Mill.hal The INI file Z axis max velocity in the INI is a lot higher than the stepgen max velocity in the HAL file. I'm sure that was hand edited. Also, the HAL file is not actually looking in the INI file for the stepgen maxaccel, so ini file settings are not having any effect. (Which version of PNCconf is this? It is making a lot of mistakes). If you look in the HAL file both stepgen accel and velocity are absolute values rather than being sucked out of the INI file. That is the way it was meant to be. PNCconf has no stepgen_max entries. If they are there - they are hand edited. Chris M -- October Webinars: Code for Performance Free Intel webinars can help you accelerate application performance. Explore tips for MPI, OpenMP, advanced profiling, and more. Get the most from the latest Intel processors and coprocessors. See abstracts and register http://pubads.g.doubleclick.net/gampad/clk?id=60134791iu=/4140/ostg.clktrk ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] CNC meeting near Chicago
On 10/02/2013 12:40 PM, Jon Elson wrote: In case people don't know, there will be a CNC-related meeting October 5th (Saturday) in Wheaton, IL. Contact saku...@gmail.com for more info, or check http://www.osmoces.org/ It is at the IIT Rice campus. I'll be there representing LinuxCNC, and bring along my minimill to demo. I will give a talk about history and capabilities of LinuxCNC at 10:30 AM, but will have the mill set up all day. Jon -- October Webinars: Code for Performance Free Intel webinars can help you accelerate application performance. Explore tips for MPI, OpenMP, advanced profiling, and more. Get the most from the latest Intel processors and coprocessors. See abstracts and register http://pubads.g.doubleclick.net/gampad/clk?id=60134791iu=/4140/ostg.clktrk ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users Wow, thx Jon need anything? I'm in Elgin, could save you carrying stuff registered / bought tix already I hadnt heard _anything_ about this thx TomP -- October Webinars: Code for Performance Free Intel webinars can help you accelerate application performance. Explore tips for MPI, OpenMP, advanced profiling, and more. Get the most from the latest Intel processors and coprocessors. See abstracts and register http://pubads.g.doubleclick.net/gampad/clk?id=60134791iu=/4140/ostg.clktrk ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] CNC meeting near Chicago
TJoseph Powderly wrote: Wow, thx Jon need anything? I'm in Elgin, could save you carrying stuff registered / bought tix already I hadnt heard _anything_ about this thx Yes, this is more a mechatronics sort of thing than specifically CNC, but I think there will be significant interest anyway. (Didn't even know anybody had to pay, I guess I get in free because I'm giving a talk.) But, I see this costs a lot less than the CNC Workshop! Jon -- October Webinars: Code for Performance Free Intel webinars can help you accelerate application performance. Explore tips for MPI, OpenMP, advanced profiling, and more. Get the most from the latest Intel processors and coprocessors. See abstracts and register http://pubads.g.doubleclick.net/gampad/clk?id=60134791iu=/4140/ostg.clktrk ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
