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RADIANCE
INSTRUMENTS
LTD.
COMPACT HYGRO-THERMOMETER
>>>>> All rights reserved <<<<<
OPTIONS
1) Compact Hygro-thermometer (RT818)
2) Compact Hygro-thermometer with external sensor (RT818E)
FEATURES
Dual-display for humidity and temperature
Maximum & minimum reading memory
Ice point alert (option 2 only)
Memory reset function
External temperature display (option 2 only)
C / F exchange
Waterproof external sensor (option 2 only)
Foldaway stand
Mounting keyhole
Velcro magic tape
SPECIFICATION
0~50C / 32~122F (internal)
-50~70C / -58~158 F (external)
20~99% RH
Display accuracy
1.5 volt, size AAA or equivalent x1 piece
External reading ≤ 0C/32F (option 2 only)
External sensor with 3 meters long sensor cord x1 piece (option 2 only)
Sensor holder x1 piece (option 2 only)
1.5 volt, size AAA battery x1 piece
Velcro magic tape x1 piece
INSTALLATION
1. Use sensor holder to fix external sensor at desired external space (option 2 only).
2. Plug external sensor into unit (option 2 only).
3. Peel off display protective sheet.
4. Install the battery with correct polarity positioning.
5. The unit will perform a self-test and display reading normally after 5 seconds.
6. Choose an installation space away from direct sunlight, rain or extreme heat and wipe the space clean.
7. Use the supplied Velcro magic tape to attach the unit onto the installation space or use the mounting
keyhole to fix the unit onto the installation space.
OPERATION
POWER ON/OFF
Press [ON/OFF] to switch thermometer off or on.
TEMPERATURE UNIT
Press [C/F] to select temperature unit.
EXTERNAL TEMPERATURE DISPLAY (OPTION 2 ONLY)
1. Press [OUT] to display external temperature.
2. Press the button again to display normally.
MAXIMUM / MINIMUM READING MEMORY
1. Press [Max/Min] to display maximum measured value.
2. Press the button once more to display minimum measured value.
3. Press the button again to return to normal display.
4. Press and hold the button until two bars “---” are displayed then release to reset memory to current
reading.
5 Reset the memory once before take new maximum / minimum reading.
MEMORY RESET
Press [RESET] on the back to reset maximum/minimum memory.
ICE POINT ALERT (OPTION 2 ONLY)
Press [ALERT] on the back to switch on ice point alert function and alarm will sound when external temperature
is ≤ 0 C.
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RADIANCE
INSTRUMENTS
LTD.
COMPACT HYGRO-THERMOMETER
>>>>> All rights reserved <<<<<
NOTE
1. Switching off the unit or pressing [RESET] will reset all current settings to default settings (ex-factory
settings).
2. If the display becomes dim please replace the battery with the same type.
3. If the unit is not in use for a long period of time then remove battery from the unit to avoid battery leakage.