Huanyang VFD speed control

[Morfeus80]

Dear All,
I have just bought a Huanyang VFD and I am wiring it. I have a doubt about how to control the speed, I have checked in many forums, but there are a lot of different theories, so I would like to start a new thread trying to clarify this issue.
The speed in the VFD can be controlled with an Analogic input (0-5V or 0-10V according to the settings), instead I would prefer to use one of the digital outputs of my UCBB. So I would like to understand if the VFD has already a RC built in circuit so I can directly wiring my PWM output to the Analogic input of the VFD.
Thanks

[cncdrive]

Well, only the VFD manual can clarify if it has a low pass filter or not and if so then what is the time constant of it.
Some have digitally implemented RC filters with adjustable time constant. If it has a time constant parameter like that then it has it.

From the UCBB you can pull the output to 10Volts with a resistor and then connect the output to the VFD. (If it has a RC filter then this should work)

Or if it does not have a built in RC filter then you can extend the above mentioned connection with one more resistor from the UCBB output to the VFD analog input and put a capacitor to between the VFD analog input and ground to form an RC filter.
The values of this resistor and capacitor depends on what PWM frequency you will use, you should size the RC components time constant at least a factor higher than the PWM frequency to let it successfully smooth the signal out.

[ger21]

So I would like to understand if the VFD has already a RC built in circuit so I can directly wiring my PWM output to the Analogic input of the VFD.

As I told you on CNC Zone, no, it doesn't, and you can't.
Most of us are using Dan's plugin.

viewtopic.php?f=14&t=432

[cncdrive]

Gerry,

But he can make an RC low pass filter using one resistor and one capacitor, so it is pretty simple to make it work.

[Morfeus80]

Said that I would prefer to use the RC filter instead that the plugin, I have read a lot of documentation and examples and it looks like that the VFD has some sort of filter, so using the PWM at high frequency it should be fine. I think this filter can be set using the parameter PD071 of the VFD, did anybody try?

[ger21]

According to the manual, it looks like PD071 adjusts the response when using analog control.

[Morfeus80]

At the end I have built a RC filter to use with the PWM signal, I will test in the next days…
Now I think I should connect also the FOR (and maybe the REV) input of the VFD. Can you explain how I should connect them to the UCBB?