Machsupport Forum

Mach Discussion => Brains Development => Topic started by: rwskinner on May 12, 2011, 03:35:59 PM

Title: How to handle VFD with no Coils
Post by: rwskinner on May 12, 2011, 03:35:59 PM

New at brains.  I had Fwd and Rev working with the Standard Serial Modbus, but now I swap over to brains and Plugin Modbus.

My Teco 7300EV only uses holding registers instead of Coils.
I have a Brain working to Start and Stop the Spindle, and another to set the RPM and Overide.
It works in Forward only at the moment.

What I would like to do is find out the state of CW and CCW and send the proper value to the Holding Register as a 16 bit value instead of a coil / bit.
Would it work to use some user vars to set Run in one and Direction in the other then just AND them together in a formula, then ship out to the register?

Bit 0 - Stop = 0, Run = 1
Bit 1 - Forward = 0, Reverse = 1

So, sending a 1 would be Run in Forward, Sending a 3 Would be Run in Reverse, and sending a Zero Stops the spindle.

Is there a better way to do this.

Title: Re: How to handle VFD with no Coils
Post by: rwskinner on May 12, 2011, 05:03:18 PM

I thought I could do something simple like:

CW Spindle On = Formula  f=1
CCW Spindle On = Formula f=3

It sure doesn't have the desired affects, especially since I can't turn off the spindle.
Right now, I'm back at having Spindle On - No Op  set to turn it on and off.

Title: Re: How to handle VFD with no Coils
Post by: rwskinner on November 06, 2011, 08:11:25 PM

Can anyone help on this?

I have a register that can only be read with FC3 and written to with FC6.
That 16 bit registers uses bit flags.

Bit 0 - Stop = 0, Run = 1
Bit 1 - Forward = 0, Reverse = 1

Sending a 0 or 1 starts and stops the VFD.
How can I tell my brain to set bit 1?

Again,  If I knew how to do this I would be happy.

CW Write a 0
CCw Write a 3
Stop Write a Zero

Richard