good morning I'm trying to turn on a vsf pump without the use of a panel to a predetermine voltage. i do know that they are turn on with a voltage which determine the speed but i dont know which wire is which and how much voltage
How about clue as to which specific pump you are working with???
Just to be clear.. Generally, the voltage level does not change the speed... The speed is determined by which pin gets the voltage.. Almost any input voltage will work. You usually have to set the speeds you want via the control panel, and then the pump will run those speeds when in the external mode.
If your control panel is not working, I doubt that adding an external control voltage will work.. But it can't hurt to try.
All this depends on the specific pump... Tell us more..