Chapter 7 Usage of Various Functions

a)PID operation explanation (without A/T function)

Measure current temperature (-200~600°C) by RTD module then digital conversion value(0 ~ 4000) is stored to D4780

PID8 instruction will calculate manipulate value (MV : 0 ~ 4000) based on PID parameter settings (P_GAIN,

I_TIME, D_TIME, etc.) and PV from RTD module. Then, the calculated MV is output to the channel 0 of D/A module.

D/A module will convert the MV to analog signal and output to the actuator (power converter).

b)operation parameters

Scan time : S_TIME=5 (sampling time = 0.5 seconds)

Auto / Manual operation setting : Auto

Output limit : Max. = 4000, Min = 0

High frequency noise removal ratio : 10

SV setting : 1300(60°C ),1350(70°C ),1400(80°C ),1500(100°C)

Current value setting : D4780(Digital value of RTD module Ch0)

BIAS setting : 0 (If only P control is used, input proper value other 0)

EN_P, EN_I, EN_D setting: input proper values

PWM setting : If enabled, input proper values.

SV Ramp setting : Input proper values.

Delta MV setting : Input proper values.

PID Algorithm setting : Select proper algorithm.

c)RTD module setting

Channel setting : use channel 0

RTD Type setting : Pt100

Digital conversion data registration area : D4780

d)D/A module setting

Channel setting : use channel 0

output range setting: DC 4 ~ 20 mA

D/A conversion data registration area : D4980

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LG Electronics 120S user manual Usage of Various Functions