Abstract: Apparatus for monitoring a fluid stream is disclosed. The apparatus includes a measurement section having a flow tube with a flow passage, a quasi-reference electrode in fluid communication with the flow passage, a working electrode in fluid communication with the flow passage, a circuit configured to measure the potential difference between the quasi-reference electrode and the working electrode; and an interface for outputting the potential difference. The quasi-reference electrode is a coated metal electrode consisting of a metal electrode having a surface that is coated at least part with a layer of an insoluble salt of the metal.

Abstract: An insert-type electromagnetic flow sensor is disclosed. The flow sensor comprises an insert, first and second electrodes supported on opposite sides of the insert and a drive coil housed in the insert. The drive coil is offset from a midpoint between the first and second electrodes and/or a width of the drive coil between the first and second opposite sides at least partially overlaps with respective inner portions of the first and second electrodes. The drive coil includes at least five turns.

Abstract: An insert-type electromagnetic flow sensor is disclosed. The flow sensor comprises an insert (12), first and second electrodes (44, 45) supported on opposite sides of the insert and a drive coil (63) housed in the insert. The drive coil is offset from a midpoint (62) between the first and second electrodes and/or a width of the drive coil between the first and second opposite sides at least partially overlaps with respective inner portions of the first and second electrodes. The drive coil includes at least five turns.