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Sper Scientific Direct

Wet Bulb Globe Heat Stress Meter SD Card Logger

Wet Bulb Globe Heat Stress Meter SD Card Logger

Regular price $518.00 USD
Regular price Sale price $518.00 USD
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Reads relative humidity (RH), air temperature (TA), dew point, wet bulb globe temperature (WBGT) and black globe temperature (TG).

Also captures sample time and date. Records data onto standard SD (Secure Digital) memory cards (like a digital camera). When full, simply exchange SD cards for unlimited data storage. The removable SD card is easy to transport and insert into a computer’s memory card slot or SD card reader. Uploads pre-formatted data to Excel, without the need for additional software and cables. Additional SD cards are readily available in a variety of memory sizes.

Features an adjustable WBGT audible alarm, min/max, auto power-off, low battery indicator and hold function. This well-made unit is extremely accurate with fast response times, and includes a fold-out tripod and large, easy-to-read backlit LCD. Comes ready to use in a soft carrying case with 6 AA batteries, instruction manual, and an SD card.

Uses optional USB Power Cable #840058, or AC Adapter #840097. N.I.S.T. traceable Certification Report is available for RH & Air Temperature only.

Globe diameter: 2¾" (70 mm)
Dimensions: 10¾" × 2½" × 1¾" (273 × 64 × 44 mm)
Weight: 1 lb. (0.45 kg)

Sper Certified
*Certification Option
N.I.S.T. traceable Certificate of Compliance available at additional cost (Select option above).


Range Resolution Accuracy
WBGT Indoor / Outdoor:
@95%RH -10 to 52°C
(@0% RH -10 to 34°C)

@95% RH 14 to 126°F
(0% RH 14 to 93°F)
0.1 Indoor:
±1°C (15 to 59°C) ±1.5°C (Others)
±1.8°F (59 to 138°F) ±2.7°F (Others)
±1.5°C (15 to 56°C) ±2°C (Others)
±2.7°F (59 to 132°F) ±3.6°F (Others)
Air Temperature -0 to 50ºC
32 to 122ºF
(@15 to 40°C)
± 1.5°F
Globe Temperature -10 to 65°C
14 to 149°F
(@15 to 40°C)
± 1.1°F
RH 5 to 95% RH ≥ 70% RH: ± 3% rdg + 1% RH,
<70% RH: ± 3% RH
Dew Point °C -25.3 to 48.9°C The dew point and wet bulb temperature values are calculated automatically using the humidity/air temperature measurement.
Dew Point °F -13.5 to 120.1°F
Wet Bulb °C @95% RH -10 to 58°C
(@0% RH -10 to 25°C)
Wet Bulb °F @95% RH 14 to 136°F
(@0% RH 14 to 77°F)


Comparison Chart


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