Extech Instruments RH250W User manual

User Manual
RH250W Hygro-Thermometer
Bluetooth® Connectivity with the ExView® Mobile App

Table of contents
1 Introduction........................................................................1
2 Safety ................................................................................2
3 FCC Compliance .................................................................3
4 Product Description ............................................................4
4.1 Meter Description .......................................................4
4.2 Function Buttons ........................................................ 4
4.3 Display Symbols.........................................................5
5 Operation...........................................................................6
5.1 Powering the Meter ..................................................... 6
5.2 Auto Power Off (APO)..................................................6
5.3 Taking Measurements .................................................6
5.4 Changing Measurement Units ....................................... 7
5.5 Data Hold Function .....................................................7
5.6 LCD Backlight............................................................ 7
5.7 MAX/MIN Readings .................................................... 7
5.8 Bluetooth Operation ....................................................7
6 Maintenance.......................................................................9
6.1 General Cleaning .......................................................9
6.2 Battery Replacement...................................................9
7 Specifications................................................................... 10
7.1 General Specifications............................................... 10
7.2 Measurement Specifications ....................................... 10
7.3 Environmental Specifications ...................................... 10
7.4 Connectivity Specifications ......................................... 11
8 Two-year Warranty............................................................. 12
8.1 Calibration and Repair Services................................... 12
8.2 Contact Customer Support ......................................... 12
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Introduction
1
Thank you for selecting the Extech RH250W Hygro-Thermometer. This meter
measures air temperature and relative humidity (RH) with its built-in sensor.
The RH and temperature readings are shown on the top and bottom rows of
the LCD, respectively.
The meter includes Bluetooth, MAX/MIN memory, selectable units of meas-
ure, auto power off, data hold, backlit LCD, and tripod mount.
Using the Extech ExView mobile app, you can pair your smart devices with
the meter using Bluetooth. The app and the W Series meters were developed
together for seamless integration. Download the free app from the App Store
(iOS®) or from Google Play (Android™).
This quality instrument is designed to provide years of reliable service, high
accuracy and simple operation. Please visit the Extech website for additional
information and world-class support.
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Safety
2
Please read all safety information before using this device
CAUTION
• Check for damage to the device’s housing, sensor, display, and battery compartment
before use. If obvious damage or abnormalities are noticed, please discontinue use
and return the device for service.
• Do not attempt to open the meter or sensor. There are no user-serviceable compo-
nents in this device.
• Replace the batteries immediately after the low battery symbol appears. If the device is
to be stored for a period of months, please remove the batteries and store separately.
• Do not store the device in high temperature or humidity environments, in flammable or
combustible areas, or where a strong electromagnetic field is present.
• This device is CE certified.
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FCC Compliance
3
This equipment has been tested and found to comply with the limits for a
Class B digital device, pursuant to part 15 of the FCC Rules. These limits are
designed to provide reasonable protection against harmful interference in a
residential installation. This equipment generates, uses, and can radiate radio
frequency energy and, if not installed and used in accordance with the instruc-
tions, may cause harmful interference to radio communications. However,
there is no guarantee that interference will not occur in a particular installation.
If this equipment does cause harmful interference to radio or television recep-
tion, which can be determined by turning the equipment off and on, the user is
encouraged to try to correct the interference by one or more of the following
measures:
1. Reorient or relocate the receiving antenna.
2. Increase the separation between the equipment and receiver.
3. Connect the equipment into an outlet on a circuit different from that to
which the receiver is connected.
4. Consult the dealer or an experienced radio/TV technician for help.
WARNING
Changes or modifications not expressly approved by the party responsible for compliance
could void the user's authority to operate the equipment.
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Product Description
4
4.1 Meter Description
1. Temperature & Relative Humidity Sensor
2. Backlit LCD (detailed below)
3. Function buttons (detailed below)
4. Tripod mount
5. Battery compartment
4.2 Function Buttons
Power / Bluetooth button
Long press to switch the device on. Short press to switch off.
With the meter powered, long press to switch Bluetooth on/off.
Short press to switch the meter off directly from the Bluetooth mode.
MAX/MIN button
Short press to cycle through MAX/MIN readings. MAX/MIN memories
are cleared each time meter power is cycled.
Data Hold / Backlight button
Short press to freeze/unfreeze the displayed reading. HOLD will display
when data hold is active.
Long press to switch the LCD backlight on/off.
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Product Description
4
Unit of Measure button
Short press to toggle the displayed temperature units (℃/℉).
APO ON/OFF With the meter on, long press the power and Hbuttons to switch APO
on/off. The APO symbol is displayed when APO is enabled. APO is
reset each time the meter power is cycled.
4.3 Display Symbols
1. Bluetooth active
2. Auto Power OFF (APO) symbol
3. Relative Humidity reading (%RH)
4. Maximum reading
5. Minimum reading
6. Data Hold mode
7. Low battery symbol
8. Temperature reading with unit of measure (℃/℉)
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Operation
5
5.1 Powering the Meter
The meter operates on three (3) 1.5 V (AAA) batteries, installed in the rear
compartment.
Long press the power button to switch the meter on. Short press the power
button to switch the meter off. If the meter does not switch on, check the bat-
teries for proper orientation.
When the low battery symbol appears on the display, replace the batteries
immediately to ensure accurate readings.
5.2 Auto Power Off (APO)
The meter switches off automatically five (5) minutes after the last button
press.
The default mode for APO is ON (the APO symbol on the display indicates
that APO is enabled).
To switch the APO function off, with the meter switched on, long press the
power and Hbuttons. The APO symbol will switch off, indicating that the
function is disabled. APO is reset each time the meter’s power is cycled.
Repeat this process to switch APO back on manually.
5.3 Taking Measurements
1. Long press the power button to switch the meter on.
2. Hold the meter in hand, set it on a table or desk, or mount it on a tripod in
the area under test.
3. Read the temperature and relative humidity readings on the LCD. The RH
reading is shown on the top row of the LCD in large digits. The tempera-
ture measurement is shown on the bottom row, in smaller digits.
4. If the temperature measurement is out of range, OL will appear on the dis-
play in place of a temperature reading. In this case, move the meter to an
area congruent with the meter’s measurement and operating
specifications.
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Operation
5
CAUTION
Do not touch or otherwise obstruct the sensor module.
Do not allow liquids to come in contact with the sensor.
Do not allow dust or other particles to enter the sensor module.
5.4 Changing Measurement Units
Short press the
℃ / ℉ button to toggle the displayed temperature units of
measure.
5.5 Data Hold Function
Short press the Data Hold (H) button to freeze/unfreeze the displayed read-
ings. While Data Hold is active, HOLD will appear on the LCD.
5.6 LCD Backlight
Long press the backlight button to switch the display backlight on or off.
Excessive use of the backlight will shorten battery life.
5.7 MAX/MIN Readings
When the device is switched on, it begins tracking the highest (MAX) and low-
est (MIN) readings.
Short press the MAX/MIN button to step through the MAX/MIN memories.
MAX is shown when the Maximum reading is displayed and MIN is shown
when the Minimum reading is displayed. The memories are cleared each time
the meter power is cycled.
Press the MAX/MIN button again to exit this mode (MAX and MIN symbols
are both off when you exit).
5.8 Bluetooth Operation
Long press the Bluetooth button with the meter on, to switch Bluetooth on
or off. This communication symbol is shown when Bluetooth is on.
The Bluetooth utility allows you to remotely monitor readings on an iOS or An-
droid smart device using the Extech ExView mobile app designed for use with
this meter.
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Operation
5
Download the ExView mobile app from the App Store for iOS devices or from
Google Play for Android devices. Instructions for mobile app use are available
from the ExView product page on the Extech website (link below).
http://www.extech.com
Switch APO off when using Bluetooth by pressing and holding the power
and Hbuttons for 2 seconds (the APO symbol will switch off). This will pre-
vent the meter from automatically switching off while you are logging data or
monitoring readings in real time on your smart device.
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