Rievtech EXM-12DC-DA-R-HMI, User Manual

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Q for Ax - Ay > 200, On = Off = 200
Description of the function
The function reads the value of the signal at the analog input Ax.
This value is multiplied by the value of parameter A (gain). Parameter B (offset) is added to the product,
hence
(Ax ∙ gain) + offset = Actual value Ax.
(Ay ∙ gain) + offset = Actual value Ay.
Output Q is set or reset depending on the difference of the actual values Ax - Ay and the set thresholds. See
the following calculation rule.
Calculation rule

If threshold On ≥Threshold Off, then:
Q = 1, if (actual value Ax - actual value Ay) > On
Q = 0, if (actual value Ax - actual value Ay) ≤Off.

If threshold On < Threshold Off, then Q = 1, falls:
On ≤ (actual value Ax - actual value Ay) < Off.
Reducing the input sensitivity of the analog comparator
You can delay the output of the analog comparator selectively by means of the "on delay" and "off delay"
SFBs. By doing so, you determine that output Q is only set if the input trigger length Trg (= output of the
analog comparator) exceeds the defined on delay time.
This way you can set a virtual hysteresis, which renders the input less sensitive to short changes.
Particular characteristics to be noted when configuring
For help on analog block parameters, refer to the Analog value processing section in eSmsConfig.
Example
In a heating control system, the supply Tv and return line temperatures Tr are to be
compared, for example with a sensor at AI2.
A control signal is to be triggered (for example "heater On") when the difference between the