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This will initiate a monitor sample and reset the time until the next sample.
Stop Monitor
6.7
To stop the current monitor session, touch
.
Control Setup
6.8
The 2960 offer two types of control, Proportional-Integral-Derivative (PID) control or Threshold. PID control attempts to
maintain the sample source at a user defined set point by adding an amount of feed stock proportional to the error.
Threshold simply triggers an alarm or feed pump when the measured sample value passes a user defined value.
The control algorithm incorporated into the 2960 is a variant of the PID algorithm used in many process controllers.
Because of the many factors which can affect control it is difficult, if not impossible, to accommodate all circumstances in
a single form of the PID control algorithm. Certain assumptions apply to the application of this control scheme of which the
user should be aware. Deviations from these assumed conditions will result in degraded regulation.
Assumptions:
1. Regulation is begun (enabled) when the analyte concentration is within ±10% of the set point.
2. The sampling interval is regular. That is, the period between samples (corrections) is constant. Random
calibration timing will degrade regulation performance if it affects sample timing.
3. Higher rates-of-change of the analyte are coupled with shorter sampling intervals to the maximum extent possible.
4. Maximum control pump on-time is kept less than the sampling interval.
NOTE: A sample performed at station 1 or 2 will not initiate regulation or affect analog output.
6.8.1 Control Type
1. From the Run menu [Monitor] tab, touch the [Configure] button.
