Emerson Process Management ROSEMOUNT 5300 Instrukcja Użytkownika Pobierz pdf (Strona 15)

Reference Manual

00809-0100-4530, Rev BA

July 2009

Rosemount 5300 Series

www.rosemount.com

Section 2 Transmitter Overview

Theory of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 2-1

Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 2-2

Components of the Transmitter . . . . . . . . . . . . . . . . . . . . page 2-5

System Architecture . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 2-7

Probe Selection Guide . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 2-9

Process Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . page 2-11

Vessel Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 2-14

Installation Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 2-15

THEORY OF OPERATION The Rosemount 5300 Series Radar Transmitter is a smart, two-wire

continuous level transmitter based on Time Domain Reflectometry (TDR)

principles. Low power nano-second-pulses are guided along an immersed

probe. When a pulse reaches the surface, part of the energy is reflected back

to the transmitter, and the time difference between the generated and

reflected pulse is converted into a distance, which calculates the total level or

interface level (see below).

The reflectivity of the product is a key parameter for measurement

performance. Media with a high dielectric constant gives better reflection and

a longer measuring range.

Figure 2-1. Measurement

Principle.

Time

Reference Pulse

Level

Interface Level

Signal Amplitude

1 2 ... 10 11 12 13 14 15 16 17 18 19 20 ... 323 324

Brak uwag

Emerson Process Management ROSEMOUNT 5300 Instrukcja Użytkownika Strona 15