A PR‑23 refractometer sensor can be located either indoors or outdoors in most climates. However, when locating a sensor outdoors, make sure to 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.
The mounting location needs to be such that sediments or gas bubbles cannot accumulate by the sensor. 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 sensor mounted on it. |
Always check that the sensor head is kept cool enough; the sensor head should not be too hot to keep a hand on. The sensor cover should not be exposed to high temperature radiation. In most cases, draft and natural convection provide sufficient air cooling if the air gets to flow freely around the sensor head.
Additional cooling is necessary when the ambient temperature is higher than +45 °C (+113 °F) or when the process temperature is above +110 °C (+230 °F) and the ambient temperature is above +35 °C (+95 °F). The air cooling is improved by blowing pressurized air against the sensor cover. The pressurized air can be supplied by the ventilation system. If no air is available it is also possible to install water cooling with PR‑10038 cooling cover (except for PR‑23‑SD where sensor head needs to be kept in original size for insertion and retraction).
| CAUTION Always mount the sensor so that the interconnecting cable points downwards from the sensor head. |