
Humidity/Temperature 
Handheld Meter
Available with USB 
and Wireless Interfaces 
RH820 Series
No Points
Standard
U USB Port Provides 
Excellent User  
Interface (RH820U)
U Wireless 2-Way 
Transmission (RH820W)
U 2 Temperature Sensors 
(Internal NTC and External 
K-Type) and Humidity 
Sensor Together
U Wet/Dry Bulb, Dew Point 
and %RH
U  MAX/MIN/AVG/REL/HOLD 
Function
The RH820 Series are low cost,  
high performance handheld meters 
available with USB or wireless 
connectivity. They offer a double 
display to show the temperature and 
humidity from built in sensors and 
can alternately display data from 
a separate Type K thermocouple 
connected via SMP type miniature 
connector. Save function allows 
storage of up to 256 readings (no 
time-stamp) to internal non-volatile 
memory. Software for USB and 
wireless versions is included to 
allow internal, external temperature, 
and RH data to be recorded by a 
PC. Interface cable is included with 
the USB version; receiver with the 
wireless version.
Specifications
Display: 3.5" digit LCD with a maximum 
reading of 1999 
Low Battery Indication: The “     ” 
is displayed when the battery voltage 
drops below the operating level
Operating Environment: 0 to 50°C  
(32 to 122°F) at <80% RH
Storage Environment: -20 to 60°C  
(-4 to 140°F), 0 to 70% RH with battery 
removed from meter
Accuracy: Stated accuracy at 23°C 
±5°C, <75% RH
Models RH820U and 
RH820W Come with 
Windows
®
 Compatible 
Software
Battery: Four 1.5V “AAA” (included) 
Dimensions: 160 H x 83 W x 38 mm D 
(6.3 x 3.3 x 1.5") 
Weight: Approx 265 g (0.6 lb) 
including batteries
Temperature Range
Range: -50 to 1000°C (-58 to 1832°F) 
Accuracy: ±(0.1% rdg +1°C) on 
-50 to 1000°C; ±(0.1% rdg +2°F)  
on -58 to 1832°F
Temperature
Sensor: Thermistor temperature sensor 
Range: 0 to 60°C (32 to 140°F) 
Resolution: 0.1°C/°F 
Accuracy: ±2°C on 0 to 10°C, ±0.5°C 
on 10 to 45°C; ±2°C on 45 to 60°C; 
±4°F on 32 to 50°F, ±1°F on 50 to 
113°F; ±4°F on 113 to 140°F
Relative Humidity
Sensor: Capacitive humidity sensor 
Range: 0 to 100% RH, 
non-condensing 
Accuracy: ±2.5% at 25°C (77°F), 
10 to 90% RH; ±5% at 25°C (77°F),  
0 to 10% RH, 90 to 100% RH
Sensor Response Time for 90%  
of Total Range: 60 sec typical
Sensor Hysteresis (Excursion  
of 10% to 90% to 10% RH): 
±1% RH typical 
RH820W Frequency Range: 
910~920 mHz, low current consumption 
less than 1 mA, the transmitting 
distance can reach 25M
RH820
 To Order Visit omega.com/rh820 for Pricing and Details
 Model No.  Description 
 RH820  Humidity/temperature handheld meter 
 RH820U  Humidity/temperature handheld meter with USB interface 
 RH820W  Humidity/temperature handheld meter wireless interface
Note: All wireless units are USA, 900 mHz frequency band versions.
Accessories 
 Model No.  Description
 HH800-ADAPTOR  AC adaptor (USB model only) 
 SC-800  Soft case for HH800 series
Comes complete with 4 “AAA” batteries, Type K thermocouple, rubber boot, NIST calibration 
(no points) and operator’s manual. RS820W also comes with software and receiver, RH820U 
comes with software and USB cable.
Ordering Example: RH820, humidity/temperature meter.
Hu-41