I am in the process of implementing EddieCurrent's safety circuit and have come across a stumbling block primarily with the Hitachi X200 interface to the circuit. I am hoping someone has a better than basic (me) knowledge of the VFD and can throw some light on the inputs to it.
In EddieCurrent's circuit he interfaces with his ABB VFD to execute a Run/Stop from the safety relay. This comes via a spindle control board and it looks like he is controlling his VFD with PWM. From what I can find out from the Hitachi manual I can input a run/stop signal to the VFD but nowhere does it explain what type of input that is. A side note: I currently control the VFD via Modbus using that purely for Start/Stop and speed control from Mach3.
Depending on what form of signal the VFD needs to switch run/stop on & off am I going to need a spindle board and have to switch to PWM control over Modbus or can I use a relay/output pin from Mach to do the switching?
Aside from these X200 gotchas I have everything else to implement the safety circuit. Hoping someone will let me know what I actually need as above.
Last edited by ozspeedway; 16-05-2014 at 12:02 PM.
To wire it just take wire from P24 (24v) on Vfd and pass it thru the relay contacts and back to Input #1 on vfd for forward. I wouldn't connect the reverse but if you do need or want it just do the same and connect to input #2 on vfd.
Edit: oh and you'll need to go into VFD parameters and setup so uses external control for Run/Stop.
Edit2: Just noticed you mention Modbus so scrap all of the above.!!. . . . . If you have on/off and spindle speed control working already then all you need to do is send the drive a signal to emergency stop if there's a problem.
To do this just program one of the inputs to code 64 via it's parameter on VFD and send it the same P24 thru the relay to input you choose. This will mean when the relay changes state IE: machine E-stop the VFD will go into E-stop.
Last edited by JAZZCNC; 16-05-2014 at 01:06 PM.
Thank you Sir! I am always for saving money, especially where CNC machines are concerned :) I found my manual and it seems to be called Safe Stop in Hitachi terms. I switch the hardware switch S8 on and it auto assigns terminal 3 to the emergency stop signal along with terminal 4. To my suprise, there is even a diagram using a PNOZ safety switch! Off to see what I need to change in EddieCurrent's circuit to a suit the X200.
Thanks for reply Dean, I've been busy for a few days.
Bruce, just post your drawings as you go, maybe start a build log.Spelling mistakes are not intentional, I only seem to see them some time after I've posted