trends

[Moran]

hello,

i need to monitor a square wave of 3V amplitude and 190 Hz.

can i display this signal on HMI trend graph? what extantion do i need ? analog input ?

i am using V570.

 

thanks.

[Joe Tauser]

Our analog inputs are not that fast.  So no, you can't trend it.

 

What exactly do you need to monitor - frequency, amplitude, or what?

 

Joe T.

[Moran]

hi joe,

 

i need to monitor the frequency and amplitude, can i use digital input? and maybe convert the 0V -3.3V square wave to open gnd and display this on trend graph?

[AlexUT]

Moran,

1.Trend have minimum sample time 0.1 sec.

2.As Joe say, Analog input is not so fast to sample 190 Hz.

3.Digital input does not sense levels, different from logical 0 and 1. So it cannot measure amplitude.

4.You can convert logical level to 0V/24V and use High Speed Counter to measure frequency, or period. But not signal amplitude.

5.With some kind of RC filter you can measure average of input signal by analog input.

 

Trend will not show high frequency signal. This is not a scope.