6 Sensors
Globe Thermometer
9.
To
power off
, press and hold the
I/O Enter key
from the main menu.
Sensors
Globe Thermometer
The globe thermometer (left position) gives an indication of the radiant heat exposure on an
individual due to either direct sunlight or hot objects in the environment. This is accomplished
by placing a temperature sensor inside a blackened copper sphere and measuring the
temperature rise. The WBGT index is based on the response of a 6 inch diameter globe. The
QUESTemp° uses a 2-inch diameter globe for a faster response time. The temperature of the
2 inch globe is correlated to match that of a 6 inch globe.
Waterless Wetbulb & Relative Humidity Sensor
The relative humidity sensor (middle position) is used to calculate the Waterless Wetbulb from
a combination of dry bulb temperature, humidity and wind speed measurements. The
waterless wetbulb is used to calculate an estimated WBGT value.
Dry Bulb Thermometer
The dry bulb thermometer (right
position) measures the ambient air
temperature. This measurement is
used in the outdoor WBGT
calculation when a high solar radiant
heat load may be present. The
series of white plates surrounding
the sensor shield it from radiant heat.
A B C
A
. Globe thermometer
B
. Relative humidity
sensor
C
. Dry bulb thermometer
Figure 1-8: Sensors identified
Sensors
