How to Set Upper and Lower Bound Frequency in Delta VFD

In this lesson, we are going to learn about how to Set Upper and Lower Bound Frequency in Delta VFD (variable frequency drive).  This is an article in which we will discuss how we can limit a frequency in upper bound and lower bound. Suppose your default frequency range is, minimum frequency range is 0 hertz and it goes up to 50 hertz.

Now, we want a set frequency range and it should start from 10 hertz, below 20 hertz, motor should not start and maximum should be 30 hertz, let's assume that.  We have different parameters in Delta VFD (variable frequency drive) and for this purpose, we have one parameter which is parameter 36, which is of upper bound of output frequency, and parameter 37 is of lower bound of output frequency.


The range we have in both parameters is from 0 hertz to 400 hertz. So in our case, we have to set upper frequency 30 hertz and lower frequency 30 hertz.  Now, go to parameter 36 and put 10 hertz, then go to parameter 37 and put 30 hertz there. This frequency will not go to below 10 hertz and will not increase from 30 hertz. This is how we can bound frequency of upper and lower frequency range.