Reference, Installation, and Operations Manual

Section 6: Meter operation

3-9000-743 Rev S

June 2013

 

 

 

Section 6: Meter operation

The purpose of this section is to instruct the user on the operation of the 3410 Series Ultrasonic Flow Meters meter, particularly for features not discussed in Section 5. It is assumed, in this section, that the user is familiar with basic ultrasonic metering.

6.1Measurement

The Ultrasonic Gas Flow Meter precisely measures the transit time of an ultrasonic wave passing through the gas to determine the mean axial velocity of the gas through the unit. The measurement paths (also referred to as “chords”) are angled to the pipe axis, and each chord has two transducers acting alternately as transmitter and receiver as shown in Figure 6-1(for

SeniorSonicTM meters) and Figure 6-2(for JuniorSonicTM meters). This permits the transit times to be measured both with and against the flow.

The transducers are mounted on the meter body at accurately known locations for each pipe size so the distance L between opposing transducers and the angle are precisely defined for the measurement path.

Figure 6-1 SeniorSonic measurement principle

Measurement

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