# Transfer Function Implementation

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Hey, I am working on with my assignment by using DAQFactory, I wonder how I may implement a Transfer Function, say

1/(0.005S+1)

for example in labjack?

I am pretty lack of knowledge about coding it in Daq and also I could find any relevant functions in Daqfactory manual sheets.

Hope someone could enlighten me~

Cheers.

Solomem

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What is S? The raw voltage reading from the LabJack? If so, just replace S with Value and put it in conversion, then apply that conversion to your input channel:

1 / (0.005 * Value + 1)

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What is S?

Sorry, " S " is the complex variable in the Laplace operator.

for example for an Integration operation the Tansfer Function should be something like: 1/S, or an Diifferentiation operation the corresponding Transfer Function will be like: S.

Thx

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Simple devices that have a transfer function include Op Amps, DC Motors, Filters, Tranformers etc.

I think it is highly unlikely that one would ever have to calculate a transfer function using a SCADA system. I can't think of any 'real world' device or devices that could be monitored and their performance assessed based on a change in transfer function.

There's no easy way to calculate a transfer function - you need to use a program like MATLAB. DAQFatory definitely isn't as powerful mathematically as MATLAB, it's not intended to be.

A transfer function is simply what happens between the input and output of a system and you can't work that out only knowing the input and output. You need to know if there are disturbances, negative/positive feedback, friction - all sorts of things.

If you know these things, then you have to figure out manually what the transfer function is. Knowing that and what the input value is you can predict waht the output should be.

The only thing you can then is monitor the output of whatever your device is using DAQFactory and create an alarm when the actual output doesn't match your pre-calculated transfer function output.