公开(公告)号：EP0975936A1

公开(公告)日：2000-02-02

申请号：EP98917463.6

申请日：1998-04-24

申请人： ABB Metering Limited

发明人： SOGHOMONIAN SALMASI, Zareh ,  JIN, Wu ,  GREGG, Ronald, David ,  MACMANUS, Gerard ,  HOWARTH, Craig, Timothy

IPC分类号： G01F1/60 ,  G01F1/58 ,  G01F1/00

CPC分类号： G01F1/586 ,  G01F1/002 ,  G01F1/58 ,  G01F1/60

摘要： A method of operating an electromagnetic flowmeter comprising a flow measurement duct, means for generating a magnetic field in fluid flowing in the duct across the direction of flow, and means for measuring a voltage thereby induced in the fluid as indicative of the flow, the method comprising measuring an output of said measuring means in the absence of said magnetic field and determining therefrom the presence or absence of fluid in the duct.