Infrared (IR) Thermometer
The infrared thermometer will measure from -40˚ to 932˚F
(-40˚ to 500˚C). Infrared readings provide measurements of only an
object’s surface. Many surfaces, like air vents, registers and grills
will quickly take on the temperature of the air moving past them at
their outermost surface. This “skin effect” allows an infrared (IR)
thermometer to provide you with inlet or outlet air temperature within
seconds of turning on an HVAC system. The distance to spot ratio of
the DTH51 is 8 to 1 (as explained in Fig 1).
1. The infrared thermometer function can be used independently of
the ambient temperature and humidity functions provided that the
differential dew point icon “ “ is not displayed at the left side
of the top line. When this icon is NOT present, you can take
infrared temperature measurements with the sensor-set retracted.
Simply press the “ “ push-button at any time to begin
taking readings.
2. To use the IR function in conjunction with the ambient
temperature and humidity functions, extend the sensor-set then
turn your meter on by pressing the “ “ push-button.
3. Press the “ “ push-button to measure the surface to
begin taking readings. The temperature that you last-measured
will be held on the top line of the LCD screen when you release
the button.
4. The last-measured IR temperature reading is used to calculate the
differential dew-point, based on the ambient temperature and
humidity sensors readings.
NOTE:
All other temperature and humidity functions are based
on the measurements provided by the sensors in the sensor-set.
5.
Key:
Press to select between Centigrade or Fahrenheit
temperature readings in both the first and second lines.
• Use to increase auto-power-off time or emissivity settings
(item 2)
• Press and at the same time to disable
auto-power-off function
6.
Key:
Press and at the same time to
turn ON/OFF laser targeting function.
• Use to decrease auto-power-off time or emissivity settings (item 2)
LCD Display
7.
IR Indicator
8.
Emissivity
9.
Battery Indicator
10.
Surface Temperature
11.
Air Temperature
12.
Air Humidity
Operating Instructions
NOTE:
The sensor-set must be extended prior to using this instrument
for any ambient air or humidity based measurements. To extend the
sensor-set, press it down, then release as shown. The sensor-set is
spring loaded and motion-dampened to ensure that it extends fully,
without stressing the components. Reverse the process to retract
the sensor-set.
IMPORTANT:
Store your DTH51 with the sensor-set retracted to keep it
away from dust, dirt and other elements.
DTH51-MAN
P. 2
Retracted
(push in to extend)
Extended
(Fig 1)
10
11
12
7
8
9
