Super Systems 9200 User Manual

Page 19

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Model 9200 Programmable Dual-loop Controller

SSi Manual SERIES 9200

19 Programmable Dual-loop

Pressing the Enter key moves you to the Burn off Setup Screen. This screen shows the parameters and

values associated with a probe burn off.

NOTE: All timer functions are in SECONDS

Burn off Time (sec), Burn off Recovery Wait Time (sec), Burn off Interval (min), Minimum Burn off

Millivolts, and Maximum Burn off Temperature, Digital IN 3 starts burn off. If the burn off does not force

the oxygen probe to read below 800 mV’s then it does not record the burn off, and if the maximum

temperature reaches a value greater than the value indicated it will shutdown the burn off procedure to
prevent damage to the probe. Signal input at Digital Input 3 could be used to initiate probe burn off.

Highlighting any of the parameters and pressing the Enter key displays a numeric keypad that allows the

operator/supervisor to change the current value. Pressing the Enter button after pressing the keypad to

change the value moves you back to the Burn off Setup Screen.


Pressing the Enter button or the Esc button at this point takes you back to the Menu Screen.

PID Loop Setup (Includes cycle time and more….)

Pressing the Enter key moves you to the PID Screen, showing you Loop 1 and it’s control parameter (i.e.

% Carbon, etc.) and Loop 2 and it’s parameter (i.e. temperature)

The TOP two blue arrows move you from one loop to the other. Pressing the down top arrow moves you

from Loop 1 to Loop 2. Below each of the loops are shown the PID parameters as they exist in the Series

9200 at that particular moment.

Highlighting the loop and pressing the Enter key activates the lower two up and down blue arrow keys,
separated by the Enter key. Using the lower up and down arrow keys allows the operator/supervisor to

highlight the parameters shown in the lower portion of the screen. These editable parameters include

Proportional Band, Reset and Rate, Set point, Pct Out (when in Manual Mode), Mode, Integral Preset, Cycle

Time, SP Change Limit, Control Mode, Low Limit, High Limit, 0 SP stops ctrl. Some of the parameters are

view only, such as Probe Millivolts, Process Variable, Pct Out (while in Auto Mode), SP Lower Limit, and SP
Upper Limit. Pressing the Enter key when the parameter is highlighted can change all of the other

parameters. This will move you to a numeric keypad that will allow you to change the specific parameter.

In some cases the keypad is non-active. You are given a menu of choices. Highlight your choice and press

the Enter key to make the appropriate selection.

Change set point overshoot protection:

When the Change Set point is set to any value other than OFF, the PID control operates normally until

there is a set point change. When a set point change occurs, the PID algorithm uses PB only (i.e. it ignores

the (I) Reset and (D) Rate) until the % output from the specified loop falls below the value specified. At

this time it begins calculating Reset and Rate and returns to normal operation.


Example: Change set point is set at 80%.

Current set point is 1500.

New set point is 1700 - % output rapidly goes to 100%, PID ignores Reset and Rate.

Temperature gets within PB, % output starts to drop.

When % output drops below 80%, PID operation returns to normal with Reset and Rate applied.


Normally overshoot is caused by a buildup of the Reset error term, by ignoring this term until the

temperature is with PB; the Reset term is minimized thus reducing the overshoot error. You should be

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