integral gain

[JohnS11]

Can somebody shows example using integral gain without  NI PID Toolkit in LabVIEW?

Thanks.

[JohnS11]

for the ni PID Toolkit,

The output returns the control output of the PID algorithm that is applied to the controlled process. This VI determines the length of the output array from the size of the process variable input array.

What does it mean if ouput is negative? what does it mean if the output is positive?

[nathand]

What are you asking here?  The output means the same thing regardless of sign - it is the the value that should be sent to the control element.  Not all control elements can accept a negative output, in which case you should limit the output range to what the controller can accept.