Powerflex 40 crash course

[jwalter 0]

I purchased a simple powder milling machine which came as 460 volt. It uses a powerflex40 as the speed control. I swapped that out for the same model in 220v & re-configed the motor wires. The machine has a power switch, a speed switch with 3 positions. the leads connect to digital input 1,2,3 of the PF40. There is a momentary on switch & an e-stop. I don't know much about the PF40. I read thru a quick start guide which helped some but a lot of it is over my pay grade. It looks like ill need to set some motor stats in the smart start program group. I don't have some of the answers to the parameters its looking for. Not sure how important those are. Then I enter in a speed setting using A51-A54. Im not sure i completely understand how to adjust the speed using either Hz, Amps or Volts. Any help would be great. Is there anyway to manually start this and ramp up the speed to see how things work. I was thinking I should be able to do that with the dial button but since I have the digital inputs connect it may not allow that manual operation. Any help would be great thanks.

[mike590 1]

To run manually set p36 and p38 to 0. Then hit the green button and the speed pot on the drive will control your speed so make sure its turned down before you hit start. Is anything hooked to input 11? It should have came with a jumper their. If you could explain what you want to do Ill give you the parameters to set. Like do you want to reverse or do you have an external speed pot and just how you want it to work. 11 supplies 24 volts to use as the estop and start. You have to have 24 volts on 1 to run. http://literature.rockwellautomation.com/idc/groups/literature/documents/um/22b-um001_-en-e.pdf Edited 25 Jul 2013 by mike590

[jwalter 0]

Thanks for the help. Ill adjust those 2 parameters to test it out. I have been reading thru the doc. I have included a schematic of my system. Its a pretty basic machine used to mill powder by spinning it thru a mesh screen & outputting a consistent size. It looks like the machine originally had 3 different speed presets that were controlled by a 3 postion switch. The PF40 is behind a cover with just a window to view the display. I've trace out the wiring & it looks like the estop is wired correctly with pins 11. Should be a matter of just programming those 3 speed setting. Thanks jason

[jwalter 0]

Also, I should note that the relay sees an input from a proximity sensor that is set up to make sure the cover is over the spinning portion of the machine. Jason

[jwalter 0]

Also, I should note that the relay sees an input from a proximity sensor that is set up to make sure the cover is over the spinning portion of the machine. So theoretically I should be able to short 1 to 11 that would bypass all of the switches & sensor? Jason

[mike590 1]

Yes if you wire 1 to 11 that will bypass any safeties. these should be your settings P36 = 1 for a momentary start P38 = 4 speed reference/ preset freq P39 = how fast you want it to speed up ( I usually just set these for 1.0 sec) p40 = how fast you want it to slow down A51 = 4 A52 = 4 A53 = 4 A71 = hertz for digital input 1 (terminal 5) A72 = hz for dig input 2 (terminal 6) A74 = hz for dig input 3 (terminal 7) ^ Those will be your 3 speeds you want the motor to run A95 = 1 to disable the reverse function Im not sure how much you know about motors but if its running the wrong direction then switch 2 of the motor leads. After you set your parameters hit the back button on the drive a few times and it will display the hertz that it is running. If you have any questions about wiring or any other funtions just let me know. Edited 29 Jul 2013 by mike590

[jwalter 0]

Awesome. Thanks for the help. I'm getting it up & running now. I don't know much about AC motors. I have always worked with DC electronics in the past. Is there a quick explanation of how Hz converts to RPM? When I set this to manual mode I found that 10,20,30 & up to 50hz seemed to make my motor sound like it was running at the correct speed. Obviously the sound of it is not a good way to judge the speed. The documentation for the machine says " the operating panel consists of an ON, OFF & 4 speed selector switch. The speed of the beater is variable from 280 to 2800 RPM with the help of an AC drive." My final question is there anyway to determine the rpm from that hz setting. So for example, lets say I wanted the 4 speeds to be off, 280, 780, 1480 & 2800 rpms. Is there a Hz setting that I can use to set those. I would make an assumption that the drive can't make the motor do something beyond its capabilities. So I shouldnt be able to damage the motor by setting this drive to high, could I? Thanks again for your help. Jason

[Joe E. 259]

You will have nameplate speed at nameplate frequency. Speed will vary with frequency, so a 60Hz motor will run at about half its rated speed at 30Hz, depending somewhat on load. You'll have to contact the motor manufacturer to determine the speed range over which it's rated to operate. Some are inverter duty motors that can operate safely all the way down to near 0 Hz and up to hundreds of Hz. Others are not.

[HKU_MS 0]

speed is determined by the number of pole pairs on the motor and the frequency minus the slip of the motor [(hzx60)/(number of pole pairs)] - slip "slip is usualy denoted in a % of RPM" so a 2 pole pair motor at 60 hz is (60X60)/2 or 3600/2=1800 minus slip name plate RPM on this motor would probably be 1756 to 1774 Range after slip is applied if you have name plate data on your motor you can prety easily figure frequncy settings for speeds as long as the output RPM is not dependent on a geared ratio drive of some sort.

[HKU_MS 0]

Almost any 3 phase motor will have some adjustability but if the original motor is still in use you should be able to go back at the same min speed max speed and not damage the device

[HKU_MS 0]

If you have a minimal amount of 480 available a auick way to check settings is just to hook up the old drive and go thru the settings 1 at a time and note the parameter settings this will take you about 15 min. on a PF 40 there are only about 75 parameters

[jwalter 0]

Could I assume the same configuration would be true for an older 160 Drive?