Measurement Notes; Data Logging; Field Of View - Extech Instruments 42580 User Manual

Field of View

The meter's field of view is 8:1, meaning that if the meter is 8 inches from the target, the
diameter of the object under test must be at least 1 inch. Other distances are shown below
in the field of view diagram. Refer to the chart printed on the meter for more information.

Measurement Notes

1. The object under test should be larger than the spot (target) size calculated by the field
of view diagram (see diagram on previous page or on side of the meter).
2. If the surface of the object under test is covered with frost, oil, grime, etc., clean before
taking measurements.
3. If an object's surface is highly reflective apply masking tape or flat black paint before
measuring.
4. The meter may not make accurate measurements through transparent surfaces such
as glass.
5. Steam, dust, smoke, etc. will affect measurements.
6. The meter compensates for deviations in ambient temperature. It can, however, take
up to 30 minutes for the meter to adjust to extremely wide ambient temperature
changes.
7. To find a hot spot, aim the meter outside the area of interest then scan across (in an up
and down motion) until the hot spot is located.
Datalogging
Overview
The Model 42580 has two datalogging modes of operation, Manual Datalogging and
Automatic Datalogging. Each has 4 sets. Each set can hold 99 readings. Data sets can be
printed in their entirety.:
• Manual Datalogging: Up to 99 readings can be stored in Sets 1, 2, 3, & 4. Data storage
is performed manually by pressing
(detailed in subsequent sections).
• Automatic Datalogging: Up to 99 readings can be stored in Sets 5, 6, 7, & 8. In
Automatic Datalogging mode, the user programs the recording start & stop date & time,
and the recording interval. Automatic Datalogging.
Diameter of Spot
1"
0.5"
4"
8"
16"
Distance to Object
5
4"
2"
Laser Beam
Sensor Beam
32"
followed by for each data point
0.63"
Model 42580 Version 2.2 11/03