M4557 - Model 9210 Nitriding Controller

the Reset (I) and Rate (D)) until the % output from the specified loop falls below the value specified. Then it will begin calculating reset and rate and return to normal operation.

Example: Change setpoint is set at 80%; Current setpoint is 1500

New setpoint 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 cautious not to set the Change Setpoint value too low - e.g. if the furnace controls 1700 in a steady state at 50% output and you set the Change Setpoint value to 40% and the PB value is low, you could find yourself in a situation where you never see 40% output and remain in a PB only control mode.

Default PID Parameters for Loop 1 - %Dissociation/Kn, Loop 2 – Temperature, and Loop 3 - Backpressure

Loop 1 Default PID Parameters

Loop 2 Default PID Parameters

Loop 3 Default PID Parameters

Proportional Band: 1.3

Proportional Band: 20.0

Proportional Band: 4.0

Reset: 0.01

Reset: 0.10

Reset: 0.10

Rate: 0.00

Rate: 0.0

Rate: 0.0

Mode: Auto

Mode: Auto

Mode: Auto

Integral Preset: 0

Integral Preset: 0

Integral Preset: 0

Cycle time: 24

Cycle time: 60

Cycle time: 60

Setpoint Change Limit: OFF

Setpoint Chazge Limit: 80%

Setpoint Change Limit: OFF

Control Mode: Dual Direct

Control Mode: Single Reverse

Control Mode: Single Reverse

Low Limit: -100

Low Limit: 0

Low Limit: 0

Hight Limit: 100

Hight Limit: 100

Hight Limit: 100

0 set point stops control: no

0 set point stops control: no

0 set point stops control: no

The Esc key on some of the screens returns you to the previous screen without any changes taking affect. From the PID Setup screen, the Esc key takes you back to the Menu screen.

Event Run Program Setup

This screen is used to start a program stored in the 9210 by contact closure between terminals 21 (Digital In Com) and 17 (Digital In 1). The value entered at program to run will start with contact closure.

Pressing Enter pops up the Current Value Screen, showing the current value in the Series 9210. To make an adjustment, enter the program number, using the numeric keypad and press the Enter key. This returns you to the original Event Run Program Screen that now shows the new program number that you have entered. If you do not wish to make the change simply press the Esc key which takes you back to the Event Run Program Screen with NO change being made to the Event Run Program.

Zone / Load TC Setup

This screen is used for Nitrider applications that utilize a Load Thermocouple in addition to the Furnace Control Thermocouple for Soak statements. The operator must manually select the Thermocouples for the

SSi Manual SERIES 9210-M4557-Nitriding

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SSI America 9210 user manual Event Run Program Setup, Zone / Load TC Setup