On 2/8/2015 11:40 AM, Dean Posekany wrote: > A little background : > > About six years ago, as I was just starting to design my shop-built > gantry machine, I came across a SUPER deal on Ebay for six sets of drive > components. Each set included a line filter, Parker OEM300 75V, 7.5A > power supply, Parker OEM750 stepper driver and a stepper motor. I didn't > know a whole lot about this stuff a the time, but I knew it was a deal I > couldn't pass up. So, they became the drive system for my CNC build. As > it turned out, only five of the six drivers worked. Thas wasn't a > problem (especially for what I'd paid for them) because my gantry is > only (at least for now) a 3-axis machine. But, six years later I've lost > two additional OEM750's and I'm now running on my last three. Another > failure and I'm down and its decision time. > > Here's my question for the worldly experience of the group. I'm retired > and this is a serious hobby machine and I don't have a great deal of > money that I can throw that this. So when the inevitable failure of the > next stepper driver occurs, what would you do? Repair the OEM750 > (~$280)? Or would you look at replacing the Parker hardware with > something else like Gecko or maybe go the Mesa route? I've really been > pleased with the stepper performance I get from the Parkers and the > software stepper generation that Linuxcnc gives me is more than fast > enough for the work I do. The repair is expensive and the drives were > released in 1997. So they're 18 years old. I just don't have enough real > world experience with this stuff to feel like I can make a good decision. > > If it was your problem, what direction would you go? > > Thanks in advance for your thoughts. > > Dean >
Dean, I've got a stack of Parker OEM750 drives here. A couple of them are new, unused. I've used them and they seem to be very good drives. I haven't had any failures. I've got three running old Bridgeport Stepper motors without problems. I think that Parker is still selling them. http://www.parkermotion.com/products/Stepper_Drives_and_Motors__4003__30_32_80_567_29.html I'm wondering why they are failing on you? Do you have the drives heat sinked? The back of the drives are smooth aluminum and are designed to be heatsinked to a backplane or the heatsink that Parker sold (use heat sink compound). If you break the drive to motor electrical connection while the motors are energized that will oftentimes kill the stepper drive. I would not pay $280 to have those drives repaired. Jon is right, the Geckos offer similar performance for less. The Parker drives show up on Ebay periodically for reasonable and unreasonable prices. At one time Parker was selling these drives for about $750 each. But I think that Gecko and Leadshine has been tough competition for Parker. I've used the Gecko 203V drives myself and have used them on industrial machines. But the Geckos need to be heatsinked as well. You can run with mixed Parker/Gecko drives on your machine. The machine won't care. I use the same timing parameters for the Geckos as I do the Parker 750's. Dave --- This email has been checked for viruses by Avast antivirus software. http://www.avast.com ------------------------------------------------------------------------------ Dive into the World of Parallel Programming. The Go Parallel Website, sponsored by Intel and developed in partnership with Slashdot Media, is your hub for all things parallel software development, from weekly thought leadership blogs to news, videos, case studies, tutorials and more. Take a look and join the conversation now. http://goparallel.sourceforge.net/ _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
