How To Set Source Of Frequency Command In Delta VFD

In this lesson, we are going to talk about the first parameter of delta vfd (variable frequency drive), which is source of frequency command.  This says, how you want to control the frequency of your delta vfd (variable frequency drive).  You have to select the source of frequency, we have various options given below;

1. Master frequency determined by digital keypad.
2. Master frequency determined by 0 volts to 10 volts input on AVI terminal.
3. Master frequency determined by 4 mili-amperes to 20 mili-amperes input on aci terminal.
4. Master frequency determined by rs 485 common port.
5. Master frequency determined by potentiometer on digital keypad.

The first option we have "master frequency determined by digital keypad" means you will be controlling the frequency by the keypad given on delta vfd (variable frequency drive). The second option we have is "master frequency determined by 0 volts to 10 volts on avi terminal" means we will be controlling the frequency of the delta vfd (variable frequency drive) by avi terminals given on the bottom side of the drive. By supplying zero to ten volts, we can control the speed by avi terminals.

The third option of controlling of the frequency we have is "master frequency determined by 4 to 20 mili-amperes input on aci terminal (we have discussed about the terminals of avi and aci in our previous article of understanding of delta vfd)", which means  we will be controlling the frequency by supplying 4 to 20 ma to aci terminals. Then we have option of "master frequency determined by rs 485 communication port,  (communication port is over there on the top of the delta vfd (variable frequency drive).  The last says, master frequency determined by potentiometer on digital keypad which means you will be controlling the frequency by the potentiometer which is placed on the delta vfd (variable frequency drive), and this parameter is set by default.


Before setting this parameters, we need to mention maximum output frequency in your delta vfd (variable frequency drive).  Many time you do not know what are the parameter set already in your delta vfd (variable frequency drive). So, the first step, what i should do, before program the new parameter, to "reset" all the parameter. What are the parameter on the delta vfd (variable frequency drive) should be "reset".

Reset The Delta Vfd (variable Frequency Drive) Parameters

To "reset" the delta vfd (variable frequency drive), and its parameter, please follow the manual of delta vfd (variable frequency drive). Parameter number 76 is the "reset" parameter of this drive, which says, if you put "00" to this parameter number 76, all the parameters can be read/set.

If you put "09" to this parameter number 76, all the parameters will be "RESET" to factory default 50 Hz. Please watch this video tutorial below for complete practical demonstration of this article and lesson to understand it better.