Gain and offset PLC

y = kx + b the equation of a straight line, the gain k refers to the slope, offset refers b.
It is generally no need to set these two parameters at the time of analog conversion, only when the external signal received by the module on the deviation signal value or only to adjust this parameter.
If the signal module is zero, then the bias b = 0, this time on the programmed y = kx, then k = y / x, this time can be adjusted according to the maximum value of the input signal corresponding to the module.