Thermosense HT-625 User manual

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HT-625 INSTRUCTION MANUAL
Humidity & Temperature Meter &
Wet Bulb Temperature
Dew Point Temperature
HOLD
+
HOLD
%RH
CEM
DT-625
TEMP.
MAX
MIN
REL MAX MIN BAT
TABLE OF CONTENTS
TITLE
1. INTRODUCTION
2. FEATURES
3. SPECIFICATIONS
4. PANEL DESCRIPTION
5. HUMIDITY AND AIR TEMPERATURE
MEASUREMENTS
6. BATTERY REPLACEMENT

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1. INTRODUCTION
The HT-625 Thermo-hygrometer has been designed to
combine the functions of a Humidity Meter, Temperature Meter,
Wet Bulb Temperature and Dew Point Temperature Meter.
The Meter is simple to operate and is commonly used in a
variety of applications which include laboratory, industrial,
engineering and professional use.
The Humidity & Temperature Meter uses a humidity &
temperature semiconductor sensor. This operation manual
contains general information and specification.
2. FEATURES
Fast Response Time %RH: 10S (90% at 25℃still air)
High Accuracy
Dew Point Temperature (-30℃~100℃/-22°F~199°F)
Wet Bulb Temperature ( 0℃~80℃/32°F~176°F)
Resolution 0.1%RH, 0. 1℃/0. 1°F
Max Hold and Data Hold Function
Micro Processor-based Design
Dual Display Temperature & Humidity
Shutdown time digitally adjustable from 1 to 120
Backlight
3. SPECIFICATIONS
Display: Large 4-1/2 dual digital LCD display with backlight
Sensor Type: A single chip relative humidity and temperature
multi sensor module comprising a calibrated
digital output.
Response Time: %RH:10S (90% at +25℃still air)
Accuracy Note: Accuracy is specified for the following ambient
temperature range: 64 to 82°F (18 to 28°C)
Sampling Rate: 2.5 samples per second
Polarity: Automatic, (-) negative polarity indication.
Over-range: “OL” mark indication.
Low Battery Indication: The “ ” is displayed when the
battery voltage drops below the
opera-ting level.
Operating Conditions: 32 to 104oF (0 to 40oC); < 80% RH
non-condensing
Storage Conditions: 14 to 140oF (-10 to 60oC); <80% RH non-
condensing

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Non-Automatic /Auto Power Off: Firstly press humidity hold
button, then press power button. After the full display appears,
releasebothbuttons.Icon“ ”willnotshow ontheLCD. The unit
will not auto power off now.
Directly press the power on/off button. The Meter will
automatically shut down after adjustment time inactivity (Sleep
Mode).
Adjustable Shutdown Time: The shutdown time is digitally
adjustable from 1 to 120 minutes. Firstly press the humidity
max/min button, then press the power button.After the full display
appears, release both buttons. icon“ ”and the current
shutdown time on the LCD. And then respectively press C and F
key to upward and downward to set the time period.
Power: One standard 9V, NEDA1604 or 6F22 battery.
Dimensions/Wt.: 150mm*72mm*35 mm/210g
Humidity / Temperature Measurement Range:
Humidity: 0%~100%RH
Temperature: –30℃~ 100℃, -30℉~ 199℉
Resolution : 0.01% RH, 0.01℃/℉.
Humidity Accuracy: + 2%RH (at 25℃, 20%～80% RH).
+ 2.5%RH (at other ranges)
Note: The measuring range is from 0% to 100%, but above 80%
and below 20% the deviation is not specified.
Air Temperature Accuracy: + 0.5℃/+ 0.9℉(at 25℃)
+ 0.8℃/+ 1.5℉(all other ranges)
4. PANEL DESCRIPTION
HOLD
+
HOLD
%RH
3
4
5
6
7
CEM
DT-625
TEMP.
MAX
MIN
REL MAX MIN BAT
1
2

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①Temperature Display
②Humidity Display
③Power ON/OFF Button: Turn the meter power
ON/OFF.
④℃: Factory set ºC. Press to change to ‘ºF’to ‘ºC’.
⑤Dew Point Button: Dew Point Measurement.
⑥’℉: Factory set ºC. Press to change to ‘ºC’ to ‘ºF’.
⑦Temperature MAX/ MIN Button: Press MAX/MIN
button to enter MAX, MIN Recording mode (manual
range only). Select the proper range before selecting
MAX MIN to ensure that the MAX/MIN reading will not
exceed the testing range. Pressing the max/min
button once for Max or twice for Min function.
⑧WBT Button: Wet Bulb Measurement.
⑨Temperature HOLD Button: Press the Hold Button
to enter the hold function. The Temperature reading
will be held when the Data Hold button is pressed.
⑩Backlight Button: Press to backlight on / off
⑪Humidity HOLD Button
⑫Humidity MAX/ MIN Button
⑬Humidity / Air Temperature Probe: Humidity &
Temperature Semiconductor Sensor inside.
5. HUMIDITY AND AIR TEMPERATURE
MEASUREMENTS
1. Hold the probe in the area to be tested & allow adequate
time for readings to stabilise.
2. Press ℉,℃, dew point, WBT Button to enter ℉,℃, dew
point Wet Bulb Measurement
3. Read the Relative Humidity and Air Temperature, dew
point temperature wet bulb temperature.
IMPORTANT NOTE:
Do not immerse the probe into liquid; it is intended for use in air
only.
Warning:
Do not expose the sensor to direct sunlight.
Do not touch or manipulate the sensor.
6. BATTERY REPLACEMENT
If the sign “ ” appears on the LCD display, it indicates
that the battery should be replaced. Open the battery case and
replace the exhausted battery with a new battery.
(1 x 9V battery NEDA1604, 6F22 or equivalent).