Model SU1352 Meter Selector

On comparison of the flowrate measured by a large size flowmeter against a preset flowrate, the meter selector opens or closes the control valve and, at the same time, in response to a full-closure signal from the control valve, selectively allows the right pulse signal either from that flowmeter or a smaller one operating in tandem to appear at the output.

This device is used in a system configured as shown in the diagram below. Using two flowmeters, large and small in capacity and flow range, with some range overlap, and a control valve to open or close the bypass line, a system in this configuration automatically selects, relative to the momentary flowrate, the right flowmeter optimally matched to handle that flowrate, thereby expanding the available overall flow range while maintaining the stated meter accuracy of individual meters.