Installation
Positioning
31
5
5 Installation
Risk of Personal Injury
When this instrument is being used in a critical process that could cause property damage and
personal injury, the user should provide a redundant device or system that will initiate a safe
process shutdown in the event that this instrument should fail.
5.1 Positioning
Sensor location depends on the application. Before deciding on a location, you need to be aware of the ambient
temperature of the location, the atmospheric quality of the location, and the possible electromagnetic interference
in that location. If you plan to use air purging, you need to have an air connection available. Wiring and conduit
runs must be considered, including computer wiring and connections, if used.
5.2 Distance to Object
The optimal distance to the measuring object depends on the selected optical lens focus (F0, F1, F2) of the sensor
and the needed measurement spot size. The correct sensor placement may vary to suit specific applications. The
following sections demonstrate the sensor placement under various conditions, where 1- or 2-color temperature
measurements deliver reasonable readings.
5.2.1 Sensor Placement in 1 Color Mode
The desired spot size on the target will determine the maximum measurement distance. To avoid erroneous
readings, the target spot size must completely fill the entire field of view of the sensor. Consequently, the sensor
must be positioned so the field of view is the same as or smaller than the desired target size.
For a list indicating the available optics, see section 2.2
The manufacturer provides a tool for calculating spot sizes, see section 15.2
Figure 5-1: Sensor Placement in 1 Color Mode
5.2.2 Sensor Placement in 2 Color Mode
The following figure shows head placement under various conditions where two-color temperature measurements
can be taken. Note, however, that if the sensor signal is reduced more than 95% (including emissivity and
obscuration of the target), the sensor accuracy also degrades.
Back-
ground
Target greater
than spot size
Target equal
to spot size
Target smaller
than spot size
best
critical
incorrect
Sensor
