Failsafe Mode Of Outputs - Endress+Hauser PROFI BUS Proline Promag 53 PROFIBUS DP Operating Manual

Proline Promag 53 PROFIBUS DP/PA
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Failsafe mode of outputs

System/process error is present
"
Caution!
System or process errors defined as "Notice messages" have no effect whatsoever on the inputs and outputs. See the information on → Page 78
Current output MIN. CURRENT
The current output will be set to the lower value of the signal on alarm level depending on
the setting selected in the CURRENT SPAN (see the "Description of Device Functions"
manual).
MAX. CURRENT
The current output will be set to the higher value of the signal on alarm level depending on
the setting selected in the CURRENT SPAN (see the "Description of Device Functions"
manual).
HOLD VALUE
Last valid value (preceding occurrence of the fault) is output.
ACTUAL VALUE
Fault is ignored, i.e. normal measured-value output on the basis of ongoing flow
measurement.
Pulse output FALLBACK VALUE
Signal output → no pulses
HOLD VALUE
Last valid value (preceding occurrence of the fault) is output.
ACTUAL VALUE
Fault is ignored, i.e. normal measured-value output on the basis of ongoing flow
measurement.
Frequency output FALLBACK VALUE
Signal output → 0 Hz
FAILSAFE LEVEL
Output of the frequency specified in the FAILSAFE VALUE function.
HOLD VALUE
Last valid value (preceding occurrence of the fault) is output.
ACTUAL VALUE
Fault is ignored, i.e. normal measured-value output on the basis of ongoing flow
measurement.
In the event of a fault or power supply failure: Relay → deenergized
Relay output
The "Description of Device Functions" manual contains detailed information on relay
switching response for various configurations such as error message, flow direction, EPD,
limit value, etc.
→ Page 137
PROFIBUS
Endress+Hauser
9.5 Failsafe mode of outputs
Note!
The failsafe mode of the current, pulse and frequency outputs can be customized by means of
various functions in the function matrix. You will find detailed information on these procedures in
the "Description of Device Functions" manual.
You can use positive zero return to reset the signals of the current, pulse and frequency outputs to
their fallback value, or reset measured value transmission via fieldbus to "0", for example when
measuring has to be interrupted while a pipe is being cleaned. This function takes priority over all
other device functions. Simulations, for example, are suppressed.
Troubleshooting
Positive zero return is activated
Output signal corresponds to "zero flow"
Output signal corresponds to "zero flow"
Output signal corresponds to "zero flow"
No effect on relay output
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