Micromod Micro-DCI: 53SL5100A Single Loop Controller - Manual (Page 109)

Single Loop Process Controller Instruction Manual
Instrument Tuning 101
12 lntroduce automatic reset slowly by decreasing TR (C107) until cycling starts.
13 Back off TR (C107) to a safe margin of about 1.5 times the value attained in Step 12.
Table 10-3. Proportional Cycle Method
Step Procedure
1 Set the process to approximately normal conditions in Manual mode.
2 Set TR (C107) first to minimum value (0.02 minutes) for several moments, then set it
to extreme maximum (200 minutes) to lock in a fixed reset value.
3 Set P.B. (C106~ to the widest value 1000%).
4 Set TD (C108) to the lowest value (0.01 minutes).
5 Switch to Auto mode.
6 Slowly reduce P.B. (C106) until process cycling starts.
7 When a slight cycle is repeatedly established, measure the peak-to-peak period of
oscillation and record it as T minutes.
8 Observe the P.B. setting and record it as P.
9 Compute the best settings as follows:
A. Proportional & Integral (PI): P.B. = 2 (P), TR = 0.8(T)
B. Proportional & Derivative (PD): P.B. = 0.8(P), TD = 0.12(T)
C. Proportional, Integral, and Derivative (PID): P.B. = 1.5(P), TR = 0.5(T), TD = 0.12(T)
Table 10-2. Trial and Error Tuning Method (Continued)
Step Procedure