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Re: VFD and PWM and G540


 

Hi,

No, the G540 pins 7 and 9 do not output a 12V supply on their own.

The G540 generates an isolated control voltage on pin 8. The amplitude of the voltage is voltage is a percentage of the voltage that is supplied to pins 7,8 of the G540. The percentage is derived from the Mark/space ratio of the PWM signal from Mach3 that is present of pin 14 of the G540's DB25 connector.

So, if the duty cycle (mark/space) ratio is 25%, then the voltage output on pin 8 of the terminal block will be 25% of the voltage you supply across pins 7,9. In this example, if you supply pins 7 and 9 with 10V, the G540 will generate 2.5V on pin 8.
If you supply pins 7 and 9 with 12V, the G450 will generates 3V on pin 8 when Mach3 outputs a PWM with a duty cycle of 25%

Note, the recommended max voltage supply across pins 7,9 is 12Vdc.

Cheers,

Peter

On 11/03/2015 3:48 AM, Chris microcnc_31@... [mach1mach2cnc] wrote:


Hello:

Can anyone tell me how the PWM signal comes out of Mach?. And if you have made
connection correctly from G540?. Pin 7,8 and 9 are connected to VFD, Does pin
7 and 9 put out 12V on their own?

Thanks

Chris



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