Valmet TS, Инструкция по установке и эксплуатации

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1. Introduction
1.1. Measurement principle
The operation of Valmet Total Solids Transmitter (Val-
met TS) is based on the measurement of microwave
propagation time.
Microwaves are a form of electromagnetic radiation,
and their propagation velocity, or flying time, is depend-
ent on the dielectric constant of the medium in which
they travel. The flying time is calculated as follows:
c = speed of light in vacuum
e
r
= dielectric constant of the medium.
In water microwaves travel at a much slower speed
than in sludge. Thus the total solids content can be
calculated based on the time it takes the microwaves
to travel through the measured mass.
The advantages of this measurement method are
its independence on medium, insensitivity to flow rate,
and single-point calibration.
1.2. Parts of the device
The device consists of the sensor unit (Fig. 2 or 3) and
the TCU operating unit (Fig. 1).
Fig. 1. Operating unit, TCU.
Fig. 2. Valmet TS-FT.
Fig. 3. Valmet TS-FT high-pressure model.
Installation & Owner's manual, OUL00489 V2.3 EN 7 Valmet Total Solids Transmitter