Instructions
 2 HT30-en-GB_V3.6 4/16 
Introduction 
Congratulations on your purchase of Heat Stress WBGT (Wet Bulb Globe Temperature) Meter. This 
meter measures and displays Heat Stress Index (WBGT), which is how hot it feels when humidity is 
combined with temperature, air movement, and direct or radiant sunlight. Black Globe Temperature 
(TG) monitors the effects of direct solar radiation on an exposed surface. It also measures air 
temperature (TA) and Relative Humidity (RH). Additional features include: selectable units of °F/°C, 
Auto power off with override, and a built-in RS-232 interface with optional 407752 Windows® 
software. This meter is shipped fully tested and calibrated and, with proper use, will provide years of 
reliable service. 
Meter Description 
1.  Black Globe temperature sensor 
2.  RH and Temperature sensors with protective cover 
3. LCD display 
4. /SET 
5. NEXT 
6. MODE/
 
7. RS-232 interface 
8.  Battery compartment (on rear) 
DISPLAY 
Symbol Function 
WBGT  Wet Bulb Globe Temperature 
TG  Black Globe Temperature 
TA Air Temperature 
RH% Relative Humidity 
OUT  Indoor (no sun) 
IN  Outdoor (in full sun) 
C/F Celsius/Fahrenheit 
  Low Battery indicator 






