Qualitrol 509ITM Series, Manual

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Rate of
change The Rate of Change feature only affects column one of the matrix. This feature,
enabled using the Rate of Change Time Period, allows the user to set a dynamic
setpoint that will actuate due to a rate of change. For example: If the control
signal is set to a Hydrogen gas input, the setpoint is set to 100 PPM, (hysteresis is
not used with the rate of change feature), the direction is set to ‘up’ and the rate of
change time period is set to 12 hours then if the absolute change of the gas
increases 100 PPM over a 12 hour time period then the relay will actuate
(assuming no other parameters are set in the matrix, otherwise the conditions for
column one will be true). The relay will de-actuate if the 12 hour window no longer
has an absolute increase of 100 PPM. This same feature can be used for a falling
control signal if the actuation direction is set to ‘down’.
Rate of
change time
period The Rate of change time period is the rolling time period used to measure the
absolute change in the control signal one. If NONE is selected then the rate of
change feature is inactive and the column is evaluated as a static setpoint.
Otherwise values of 2 to 168 hours may be entered for the rate of change time
period to evaluate changes in the control signal one.
Note:
If you are using a relay as a Control Signal, a closed contact would read ‘0’ and an
open contact would read ‘100’; therefore, a setpoint should be between those two
parameters (e.g. 50).
Cancel and Load Buttons
This section of the Output Relay Setup window includes the buttons described below.
Cancel Button Cancels any changes made and returns you to the Setup window.
Load Button
Saves all the settings from this window to the ITM509 and returns you to
the
Setup window.