Example: alarm response of the flow input (4 to 20 mA)
1.
Select "Free configuration" for the alarm response (Set-up/Basic set-up/Alarm response)
2.
Select the flow input (Setup/Inputs/Flow.., called Promag here, for example) and assign the
desired range limits and alarm functions under "Alarm response".
In this example, the flow value is extrapolated between 4 mA and the range
violation point of 3.8 mA, extrapolated again between 3.8 mA and the cable open circuit limit of
3.6 mA and evaluated with the default value 0 below 3.6 mA.
Since "Fault" was selected as the alarm type for the cable open circuit, all the outputs of the appli-
cation to which this input is assigned assume the configured failsafe mode (e.g. output a fixed value
of 22 mA).
The upper range limit and the upper cable open circuit are also configured in this way.
b) Temperature inputs
The response in the event of a cable open circuit (infinite resistance) can be defined for the temper-
ature inputs (e.g. PT100) (the measuring range limits are fixed).
c) Pulse inputs
The alarm response cannot be defined for pulse inputs (incl. PFM signal). (In other words, the cable
open circuit or a frequency of 0 Hz are interpreted identically by the device)
Configuration parameters for the alarm response of the applications
The alarm response can be defined for the following process errors under Set-up/Applications....
(see also BA144R, Chap. 5.3)
Steam: wet steam alarm, phase transition
Gas: range overshoot
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