[hscess]

Is it possible to issue the m3 and m4 command at the same time. My VFD requires it. I am new to cnc machining. I have the free trial version of Mach 3 and have everything working good except turning on my vfd. One relay will turn on the vfd m3 in fwd, but when I issue the m4 for reverse it turns off the m3 and everything stops. I need m3 and m4 to turn on both relays at the same time for reverse. Any help will be appreciated.

[Al_The_Man]

That is not standard, and it is not the VFD itself that decides how the M3 & M4 it is the hard wiring input connections to the VFD and how they are set up, sounds like the fwd rev VFD inputs are wrongly configured..
Why don't you issue a M5?
The requirement for M3 & M4 to be issued for reverse is decided by Mach and the VFD input contacts.
What VFD is it?
Al.

[eman5oh]

That sounds more like you have an enable and a direction contact. My vfd works that way but it is controlled with Linux CNC. I am sure Mach would be able to be configured like this as it is a fairly standard way to control a vfd.

[mactec54]

hscess

As Al has said you have, the VFD input wiring configured wrong, what type of motor do you want to reverse