VEGAPULS WL 61 - 4 … 20 mA/HART - two-wire

9 Diagnosis, Asset Management and serviceError Cause Rectification4 … 20 mA signalnot stable4 … 20 mA signalmissingCurrent signalgreater than22 mA or lessthan 3.6 mA– Level fluctuations– Electrical connectionfaulty– Voltage supplymissing– Operating voltagetoo low orload resistancetoo high– Electronicsmodule in thesensor defective– Set damping according to theinstrument via the indicating andadjustment module or PACTware/DTM– Check connection according tochapter "Connection steps" andif necessary, correct according tochapter "Wiring plan".– Check cables for breaks; repair ifnecessary– Check, adapt if necessary– Exchange the instrument or send itin for repairTreatment of measurementerrors with liquidsThe below tables show typical examples of application-related measurementerrors with liquids. The measurement errors are differentiatedaccording to the following:• Constant level•• FillingEmptyingThe images in column "Error pattern" show the real level with a brokenline and the level displayed by the sensor as a continuous line.Level120time1 Real level2 Level displayed by the sensorInstructions:• Wherever the sensor displays a constant value, the reason couldalso be the fault setting of the current output to "Hold value"• In case of a too low level indication, the reason could be a lineresistance that is too high38VEGAPULS WL 61 • 4 … 20 mA/HART - two-wire38061-EN-121011