Coriolis flowmeter with zero checking feature

摘要

Descriptions are provided for implementing flowmeter zero checking techniques. In operating a flowmeter, it may be the case that, even if previously calibrated, the flowmeter will produce erroneous measurements, will indicate a non-zero flow during a period of zero flow. Therefore, zero checking features are provided that allow for fast and accurate determinations of the zero-flow values, for use in adjusting later measurements. The zero-checking features include a button attached to an exterior of a flowmeter, so that it is easily accessible to an operator of the flowmeter. The button, in conjunction with an internal zero checking system, allows for a display of a zero value in response to a request from the operator of the flowmeter.

主权项

1. A system for calibrating a flowtube, the system comprising:
a transmitter configured to induce motion in the flowtube containing fluid, the transmitter comprising:
a contact input,a measurement module configured to determine a sensed property value indicative of a sensed property of the fluid based on the motion of the flowtube, anda zero-checker module configured to determine a calibration value based on the sensed property value over a pre-determined time period during which the fluid contained in the flowtube is actually stationary; a first switch configured to activate the zero-checker module, the switch coupled to the transmitter through the contact input, and; wherein the first switch is configured to close the flowtube such that the fluid contained in the flowtube is stationary, and a second switch is configured to deactivate the zero-checker module and to open the flowtube such that the fluid contained in the flowtube flows.