Choosing mounting location - PR-43-AP - PR-43-AC

PR-43-AC/AP User Guide

Document code
English (United States)
Document type
User guide

To make sure that the refractometer produces reliable readings from the process, select the mounting location so that sediments or gas bubbles cannot accumulate by the refractometer. Good flow velocity is essential in keeping the prism clean.

CAUTION If the process pipe vibrates, support the pipe. A vibrating pipe might damage the in‑line refractometer mounted on it.
CAUTION Always mount the refractometer so that the interconnecting cable points downwards from the refractometer head.

A Vaisala K‑PATENTS® in‑line refractometer can be located either indoors or outdoors in most climates. However, when a refractometer is located outdoors, provide some basic protection against direct exposure to sunlight and rain. Take special care if the pipe wall is translucent (for example, made of fiberglass), as light from outside reaching the prism through the pipe wall may disturb the measurement.

Do not expose the refractometer cover to high temperature radiation. In most cases, draft and natural convection provide sufficient air cooling if the air gets to flow freely around the refractometer head. The air cooling is improved by blowing pressurized air against the refractometer cover. The pressurized air can be supplied by the ventilation system.

Additional cooling is necessary when the internal temperature of the refractometer is in the red temperature range shown in the following figure. For additional cooling, mount a PR‑14038 cooling cover for cooling with water.

Figure 1. Compact refractometer internal temperature at different ambient and process temperatures
Internal temperature in green area
Normal operation
Internal temperature in yellow area
High internal temperature warning
Internal temperature in red area
High internal temperature, use cooling cover