PDA

View Full Version : 23 Nema Electronics Kit and VFD Control



Op4
03-23-2015, 12:21 AM
I replaced my G540 and power supply with a Nema 23 electronics kit with ESS, but I am trying to simplify my system and get rid of all the extra serial/parallel port modbus mess.

Is it possible to use the Mach3 Interface Board (BL-Mach-V1.1) that is inside the electronics enclosure to control a VFD? I see PWM outs and other hook ups on that board, but I have not seen anyone post about it.

I will probably just call cncrouterparts tomorrow, but I figured I would try here first.

Thanks!

naPS
03-23-2015, 01:00 AM
I replaced my G540 and power supply with a Nema 23 electronics kit with ESS, but I am trying to simplify my system and get rid of all the extra serial/parallel port modbus mess.

Is it possible to use the Mach3 Interface Board (BL-Mach-V1.1) that is inside the electronics enclosure to control a VFD? I see PWM outs and other hook ups on that board, but I have not seen anyone post about it.

I will probably just call cncrouterparts tomorrow, but I figured I would try here first.

Thanks!

You can definitely use the PWM output if there's one available - assuming your VFD has a 0-10vdc control signal input. I was using that with my kit, but switched to Modbus control as I was able to get precise speed control with zero tuning necessary. I used a USB -> RS485 dongle to get the Modbus stuff working along with the plugin available for Mach3.

To use the PWM, and assuming you have the Chinese VFD, you'll need to set one of the relays on your board to close when you want the spindle to start spinning, and then connect the digital common through the relay to the fwd pin on the VFD. You then connect the analog common to the 10vdc ground side, and the PWM pin to the Vin pin on the VFD. Pretty simple stuff. There's some tuning you need to do to get the VFD speeds to match what you want it to match, and you have to change some parameters on the VFD itself - mainly 001 and 002 both getting set to '1', and you should be good to go.

Op4
03-23-2015, 01:15 AM
thanks for the reply :)

I have the Hitachi x200 and never got modbus speed control to work. I was able to get it to turn off and on, but the speed never worked. I was following the popular Hitachi modbus thread in the Mach3 forums, but just couldn't get things to work. I was using the RS232 converter (non-usb).

Do you have any threads that you can share for the usb modbus version? Maybe I can go that route.

naPS
03-23-2015, 01:18 AM
Yeah, just do a search on amazon for USB to RS485 converter - I picked one up for like 3 bucks I believe. The plugin that I'm using is specifically for the Hyungang VFD's though, and won't work with the Hitachi, which is a bummer, because it works great.

Op4
03-23-2015, 05:33 PM
Ya know...you got me thinking. I am going to try using a USB to RS485 opto isolated converter (more high end one). So far all the failed usb experiments with USB converters have been reported to be the cheaper non-isolated types.

By "plugin" do you mean the brain? I have a brain that works for others, but since my converter is not sending on the com port correctly, the brain obviously will not work thus getting a new converter. I will report back if this works.

naPS
03-23-2015, 07:15 PM
Heh, it seems like the Mach3 development is pretty fragmented - I've seen 'brains' mentioned before, but have never used one. There's actually a plugin specifically for the cheap Chinese VFD's that installs in the plugins folder, perhaps that's the new term for 'brains'?

Op4
04-12-2015, 10:53 PM
Reporting back....a SIIG usb converter did the trick! So Modbus is working. I will never by a cheap converter again lol.