LG Electronics 120S user manual Usage of Various Functions

Chapter 7 Usage of Various Functions

(4)parameter setting and explanation

(a)PID8 instruction parameter setting and explanation.

①Scan time

Scan time is the period of reading data (sampling), and also 10 times scaled up. The range of sampling time is

0.1~ 10 seconds, and actual input range is 0 ~ 100. Generally, Scan time of Digital PID control should be less than 1/10 of time constant of system response for better performance. Time constant is the time taken the system’s step response reaches to the 63% of steady state.

②Operation mode

Select automatic or manual operating mode

③Manual operate range

When manual operation is designates , manual operation value designates.(input range : 0 ~ 4000)

④Output limit value

Designate minimum and maximum values of available manipulate value.(range : 0 ~ 4000)

⑤High frequency noise removal ratio

high frequency noise removal ratio is used for derivative control operation, and shows the ratio of high frequency noise depression. If there is a lot of high frequency noise in the control system, select the value as higher value.

Otherwise, leave the 1. The range of parameter is 0 ~ 10 and it is not scaled up, so input the designated value directly.(it is possible that parameter value designates ‘D’ area also)

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