Endress+Hauser Proline Promag 51, Руководство по эксплуатации

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9 Trouble-shooting Proline Promag 51
92 Hauser
9.5 Response of outputs to errors
!
Note!
• The failsafe mode of totalizers, 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.
• In custody transfer mode, positive zero return cannot be activated.
Positive zero return and failsafe mode:
You can use positive zero return to set the signals of the current, pulse and frequency outputs to
their fallback value, 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.
Failsafe mode of outputs and totalizers
Process/system error is current Positive zero return is activated
(Not possible in
custody transfer
mode )
"
Caution!
• In non-custody transfer mode the following applies:
System or process errors that have been defined as “notice messages” have no effect on the inputs and outputs.
Please refer to the information on Page 56.
• In custody transfer mode the following applies:
Promag 51 always classifies and treats “notice messages” as “fault messages”. If the status output, in contrast to the
factory setting (= FAULT MESSAGE), is set to “NOTICE MESSAGE”, the status output no longer switches in the
event of notice/fault messages.
Current output MINIMUM 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 “Descrip-
tion of Device Functions” manual).
MAXIMUM 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 “Descrip-
tion of Device Functions” manual).
HOLD VALUE
Measured value display on the basis of the last saved
value preceding occurrence of the fault.
ACTUAL VALUE
Measured value display on the basis of the current
flow measurement. The fault is ignored.
Output signal corresponds to “zero
flow”
Pulse output FALLBACK VALUE
*)
Signal output
→
no pulses
ACTUAL VALUE
Fault is ignored, i.e. normal measured value output
on the basis of ongoing flow measurement.
* fixed setting in custody transfer mode
Output signal corresponds to “zero
flow”