Page 1 of 1

Knee mill Low gear reversing on VFD

Posted: Wed Jan 08, 2014 12:46 pm
by bloomingtonmike
Needing some advice on how to wire a reversing action on my VFD (WJ200) when I select the low gears on my knee mill. How have folks done this in the past.

Re: Knee mill Low gear reversing on VFD

Posted: Wed Jan 08, 2014 2:10 pm
by Centroid_Liviu
Please follow the table below to connect the Hitachi WJ200-015SF drive to the ALLIN1DC. Make sure that there is a jumper installed between pins L and PLC on the inverter. The 0-10VDC COM signal must be connected to the L that is in between the OI and AM pins on the inverter. Make sure that A001 is set to 01 and that A005 is set to 00.

Re: Knee mill Low gear reversing on VFD

Posted: Wed Jan 08, 2014 7:15 pm
by bloomingtonmike
Maybe I was not clear. I have a hall effects or magnetic switch/lever of some kind on my mill. When it is flipped down the Mill is in low gear/slow speeds. It reverses the direction of the cutter. I need that switch wired to the VFD so that when It is in low gear the VFD will still spin the motor the correct direction.


UNLESS - Is there a connection I make for that switch on the Allinone?

Re: Knee mill Low gear reversing on VFD

Posted: Wed Jan 08, 2014 7:19 pm
by bloomingtonmike
Image

The small arm in the middle of the head in this picture with the black ball knob.

Re: Knee mill Low gear reversing on VFD

Posted: Wed Jan 08, 2014 7:26 pm
by cnckeith
Mike, The hi low range switch is wired into the all in one. the all-in-one will read that input and then determine the proper CW or CCW signal to send to the inverter.
take a look at the all-in-one full size schematic (or the individual sections included with the CD) and you'll see where to connect the hi/lo switch and the spin forward and spin reverse signal that goes to the inverter. This is the way most all machines connect up that have a back gear head. works great.

Re: Knee mill Low gear reversing on VFD

Posted: Wed Jan 08, 2014 7:58 pm
by bloomingtonmike
Great idea. I will check that out again tonight. Had forgot about that.

Do those switches get power typically? Never wired one before. (Maybe diagram shows that too?)

Re: Knee mill Low gear reversing on VFD

Posted: Wed Jan 08, 2014 10:45 pm
by cncsnw
Typically it is INP12.

The switch should be open in high gear, closed in low gear. If your switch is the other way around, then add 512 to Machine Parameter 178.

You need to set the low range ratio (fraction of high-range speed that you get in low range) in Machine Parameter 65. Since your head runs backwards in low gear, you need to enter that fraction as a negative number. For example, if you have 8:1 reduction, then set P65 = -0.125.

If the switch is a 3-wire proximity sensor, then yes: you need to wire power to it (plus, minus, and signal). Since you probably have the INP9-12 configured as 12VDC current-sourcing inputs, you hope that your proximity sensor is an NPN sensor which will function on 12V. If it is not, then you either need to reconfigure that bank (and the other inputs that are on it), or change your PLC program to look for the low-range switch elsewhere (INP13, for example).

Re: Knee mill Low gear reversing on VFD

Posted: Wed Jul 23, 2014 8:56 pm
by Mountainman
lets say that the controller knows that you are in high or low gear via the appropriate input. Where does everything go from there? If your programmed S command requires a high or low gear and your handle happens to be in the wrong position, what does the controller do? Does it stop all motion and tell you to change gears before initiating M03 or M04? Does the controller send a reverse command to the VFD if the spindle will be reversed due to gear setting?

Re: Knee mill Low gear reversing on VFD

Posted: Thu Jul 24, 2014 5:06 am
by diycncscott
Mountainman wrote:lets say that the controller knows that you are in high or low gear via the appropriate input. Where does everything go from there? If your programmed S command requires a high or low gear and your handle happens to be in the wrong position, what does the controller do? Does it stop all motion and tell you to change gears before initiating M03 or M04? Does the controller send a reverse command to the VFD if the spindle will be reversed due to gear setting?
If your programmed S command requires a high or low gear and your handle happens to be in the wrong position, what does the controller do?

Because every machine is different (and every operator uses the machine in his/her own manner), the controller has no way of knowing whether the commanded spindle speed requires a specific range though it could be programmed, through a combination of a custom macro and custom PLC program, to react to a spindle speed command received while in an inappropriate gear range. For more information on PLC programming and macros, please see the CNC11 PLC programming manual and the CNC11 Operators Manual.
http://www.ajaxcnc.com/ajax-cnc-manuals/ or call for a quote

Does the controller send a reverse command to the VFD if the spindle will be reversed due to gear setting?

Yes, if configured to do so. The ratio of spindle ranges is defined in parameters 65-67. If you negate the value in one of those parameters, current PLC programs will reverse the spindle when the gear range input(s) indicate that the machine has been placed in that range. Example: Your low range is a back gear with a spindle motor to spindle ratio of 10:1, set parameter 65 to -.1 to have the control automatically reverse the spindle when placed in low range. All CW and CCW commands in manual and auto mode will respond as expected.