Proline Promass 83E/F/O Modbus RS485 Operating Instructions

TroubleshootingProline Promass 83 Modbus RS485!Note!9.5 Response of outputs to errorsThe failsafe mode of totalizers, current, pulse and frequency outputs can be customized by meansof various functions in the function matrix. You will find detailed information on these proceduresin the "Description of Device Functions" manual.You can use positive zero return to reset the signals of the current, pulse and frequency outputs totheir fallback value, or reset measured value transmission via the fieldbus to '0'. This is used, forexample, when measuring has to be interrupted while a pipe is being cleaned. This function takespriority over all other device functions. Simulations, for example, are suppressed.Failsafe mode of outputs and totalizersProcess/system error is presentPositive zero return is activated" Caution!System or process errors defined as "Notice messages" have no effect whatsoever on the outputs. See the information on ä 41Current outputMIN. CURRENTOutput signal corresponds to "zero flow"The current output will be set to the lower value of the signal on alarm level depending onthe setting selected in the CURRENT SPAN (see the "Description of Device Functions"manual).MAX. CURRENTThe current output will be set to the higher value of the signal on alarm level depending onthe setting selected in the CURRENT SPAN (see the "Description of Device Functions"manual).HOLD VALUEMeasured value display on the basis of the last saved value preceding occurrence of thefault.ACTUAL VALUEMeasured value display on the basis of the current flow measurement. The fault is ignored.Pulse outputFALLBACK VALUESignal output no pulsesHOLD VALUELast valid value (preceding occurrence of the fault) is output.ACTUAL VALUEFault is ignored, i.e. normal measured-value output on the basis of ongoing flowmeasurement.Output signal corresponds to "zero flow"Frequency outputFALLBACK VALUESignal output 0 HzFAILSAFE VALUEOutput of the frequency specified in the FAILSAFE VALUE function.HOLD VALUELast valid value (preceding occurrence of the fault) is output.ACTUAL VALUEFault is ignored, i.e. normal measured-value output on the basis of ongoing flowmeasurement.Output signal corresponds to "zero flow"TotalizerSTOPThe totalizers are paused until the error is rectified.ACTUAL VALUEThe fault is ignored. The totalizer continues to count in accordance with the current flowvalue.HOLD VALUEThe totalizers continue to count the flow in accordance with the last valid flow value(before the error occurred).Totalizer stopsModbus RS485In the event of faults, the value "NaN" (not a number) is transmitted instead of the currentmeasured value.–Page 100 • MN0M030Issue/Rev. 0.2 (12/12)