YOKOGAWA PH402G - Page 61

Parameter setting 5-29
IM 12B6B3-E-H
Code Display Function Function detail X Y Z Default values
Contacts (continued)
44 *D.TIME Delay time Minimum relay switching time 0.2 sec.
*PH.HYS Hysteresis pH Minimum pH/ORP change for relay reset 0.1 pH
*mV.HYS Hysteresis ORP after switching 10 mV
*rH.HYS Hysteresis rH Minimum rH change for relay reset 0.2 rH
after switching
*T.HYS Hysteresis temp. Minimum temperature change for relay 1 °C
reset after switching (fig. 5-2)
45 *RANGE Proportional range When proportional control selected 1 pH
in code 40, 41, 42 or 43 (10 mV)
*rH.RNG Proportional range rH When rH proportional control selected in 2 rH
code 40, 41, 42 or 43
*PER. Duty cycle period Pulse control On time + Off time (fig. 5-3) 10 sec.
*FREQ. Maximum frequency 100% value for frequency control (fig. 5-4) 70 p/m
46 *tI.CNT Integral time Integral time for relay controls when 100 sec.
PI is set
47 *EXPIR Expiry time Warning of ineffective control action On 0 0 Off
Warning of ineffective control action Off 1
*tE min Set expiry time 15 min
48-49 Not used
t (sec)
LED off
Hys.
LED on
Delay time Delay time
LED off
pH/mV
Setpoint
90%
100
50
0
on
t t
off
10%
50%
50%
10%
90%
100
50
0
SC
0.3 s
Fig. 5-3.
Fig. 5-4.
pH
% of setpoint value
pH
% of setpoint value
% duty cycle control
Setpoint
Proportional
range
Time
Setpoint
Proportional
range
Time
Maximum pulse frequency
50 % pulse frequency
No pulses
% controller output
Fig. 5-2.