Inline Refractometer Sensor; Sensor Description - Vaisala K-PATENTS PR-23 Series Instruction Manual

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2 Inline refractometer sensor

2 Inline refractometer sensor

2.1 Sensor description

Figure 2.1 below shows a cutaway picture of a PR-23 inline refractometer sensor. The
measurement prism (A) is flush mounted to the surface of the probe tip. The prism
(A) and all the other optical components are fixed to the solid core module (C), which
is springloaded (D) against the prism gasket (B). The light source (L) is a yellow Light
Emitting Diode (LED), and the receiver is a CCD element (E). The electronics is pro-
tected against process heat by a thermal isolator (K) and cooling fins (G). The sensor
processor card (H) receives the raw data from the CCD element (E) and the Pt-1000
process temperature probe (F), then calculates the refractive index n and the process
D
temperature T. This information is transmitted to the Indicating transmitter.
(G) Cooling fins
(E) CCD element
(H) Sensor
processor
card
(D) Disc spring
(K) Thermal isolator
(L) Light source
(C) Core module
(A) Prism
(B) Gasket
(F) Temperature probe
Figure 2.1 PR-23 sensor structure