Super Systems 9205 Series - Manual (Page 87)

Series 9205 Operations Manual Rev A 86
Cycle Time
This field is typically set to the valve travel time multiplied by 1.5. The range is 0 – 300.
Setpoint Change Limit
This is a smart time feature that allows Process Loop to use PB only without Reset until the Process
Variable drops below the percent output set under this category.
It is used to eliminate overshoot.
The Output percentage selected under this category must be above the normal operating output percentage
of the furnace at heat.
The options are: OFF, 80%, 70%, 60%, 50%, 40%, 30%, or 20%.
Example: If the furnace runs at 40% output at heat for the maximum load, the setpoint change limit should
be set to 60%.
Low Limit
This is the low limit for the loop. The range is –100 to 100.
High Limit
This is the high limit for the loop. The range is –100 to 100.
0 Setpoint Stops Control
If the Setpoint is zero, then all outputs are turned off. The option is either Yes or No.
IN1 high limit shuts down ctrl
If input 1’s high limit is reached, then all outputs are turned off. The value can either be Yes or No.
IN2 high limit shuts down ctrl
If input 2’s high limit is reached, then all outputs are turned off. The value can either be Yes or No.
IN3 high limit shuts down ctrl
If input 3’s high limit is reached, then all outputs are turned off. The value can either be Yes or No.
PID Auto Switch
This is the PID auto switch field. The value can either be Yes or No.
PID auto switch is a feature within the instrument that allows multiple PID Loops to be used for various
temperature ranges. This feature can be extremely helpful when a single PID Loop is not accurate across a
wide temperature range. The most common indication that PID auto switching may improve furnace ability
is failure to pass Temperature Uniformity Surveys (TUS). In many examples, a certain PID Loop may prevent
under- or over-shoot at normal operating temperatures; but produce unacceptable overshoot at lower
temperature.
This feature allows the user to utilize (up to) three distinct loops to obtain more accurate heating curves. In
most applications, it is helpful to use the built-in Tuning Assistant feature to determine appropriate PID
values. These values can be recorded and manually entered as described below. The chart below
demonstrates this feature.