Extech Instruments RPM250W User manual

User Manual
RPM250W Laser Tachometer
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 Parts ...............................................................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 Tachometer (RPM) Measurements .................................6
5.4 Counter Measurements (with illuminated objects) ..............7
5.5 Counter Measurements (with external illumination) ............7
5.6 Data Hold Function .....................................................8
5.7 LCD Backlight............................................................ 8
5.8 MAX/MIN Readings in RPM Mode..................................8
5.9 Bluetooth Operation ....................................................8
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 RPM250W Laser Tachometer. This meter
measures rotations per minute on equipment such as fan blades, rotors, tur-
bines, and similar machinery. The RPM250W is also a counter where items
on a conveyor, for example, can be counted. Measurements are made using
the built-in photo-electric sensor, situated at the top of the meter. Readings
are shown on the backlit LCD.
The meter includes Bluetooth connectivity, MAX/MIN memory (in RPM mode),
auto power off, data hold, Laser pointer, 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 housing or access the sensor module. There are no
user-serviceable components in this device.
• Do not point the Laser beam toward the eyes. See Laser safety label below:
• 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 Parts
1. Photo-electric sensor and Laser pointer lens
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 and Counter Reset button
In RPM mode, short press to view the MAX/MIN readings; Long press to
clear the readings.
In Count mode, short press to reset the count to zero. The COUNT dis-
play text will flash twice.
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
Tachometer/Counter and Laser button
Short press to toggle Tachometer (RPM) and Count modes.
Long press to switch the Laser pointer on/off. The Laser pointer symbol
is shown when the Laser is on.
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. Tachometer/Counter readings
2. Laser pointer symbol
3. Monitor symbol appears when the sensor detects a reflection from the
supplied tape or when an object is counted
4. Data Hold mode
5. Maximum reading
6. Minimum reading
7. Low battery symbol
8. Auto Power Off (APO) symbol
9. Bluetooth active
10. Tachometer (RPM) and Counter (COUNT) modes
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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 Tachometer (RPM) Measurements
WARNING
To avoid personal injury and damage to the meter and other machinery, keep a distance of
at least 50 mm (2 in.) between the tachometer and the measured object.
1. Switch off the device under test so that it is not moving.
2. Cut off a 0.5 x 0.5 in. (12 mm x 12 mm) piece of reflective tape (supplied)
and affix it to the device under test.
3. Long press the power button to switch the meter on and short press the
mode button (if necessary) so that RPM is shown.
4. Switch on the device under test so that it begins moving.
5. From a distance of 2 to 20 in. (50 to 500 mm), point the meter’s sensor
(top) towards the reflective tape. For best results, the vertical angle of inci-
dence should be < 30°.
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Operation
5
6. When the sensor detects a reflection from the tape, the monitor symbol
appears on the LCD.
7. The five-digit LCD read-out shows the RPM measurement.
8. If the measurement is > 99,999 RPM, OL will appear on the display in
place of a reading.
NOTE
When measuring < 50 RPM, the period of the pulse is quite long and requires that the meter
be kept still to ensure accuracy. Wait at least two pulse signals for the best accuracy. If the
pulse is longer than 7 seconds, the RPM reading will not change.
5.4 Counter Measurements (with illuminated objects)
1. Long press the power button to switch the meter on.
2. Short press the mode button so that COUNT is displayed.
3. Position the meter 2 to 20 in. (50 to 500 mm) from the object under test.
For best results, the vertical angle of incidence should be < 30°.
4. Switch on the machinery under test so that it begins moving.
5. Each time an illuminated object passes the meter sensor, the count incre-
ments by 1 and the monitor symbol appears.
6. Short press the MAX/MIN button to reset the counter to zero (COUNT will
flash twice).
7. When the counter is > 99,999 units, OL will display.
5.5 Counter Measurements (with external illumination)
1. Long press the power button to switch the meter on.
2. Short press the mode button so that COUNT is displayed.
3. Long press the Laser button to switch off the Laser.
4. Position the meter 2 to 20 in. (50 to 500 mm) from the object under test.
For best results, the vertical angle of incidence should be no greater than
30°.
5. Position the external optical source opposite the meter, on the other side
of the device under test (so the device under test is situated between the
meter and the light source).
6. Switch on the device under test so that it begins moving.
7. As each object passes between the meter sensor and the optical source,
the count increments by 1 and the monitor symbol appears.
8. Short press MAX/MIN to reset the counter to zero (COUNT will flash
twice).
9. If the count > 99,999, the display will show OL in place of a reading.
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Operation
5
5.6 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.
5.7 LCD Backlight
Long press the backlight button to switch the display backlight on or off.
Excessive use of the backlight will shorten battery life.
5.8 MAX/MIN Readings in RPM Mode
In RPM mode, short press the MAX/MIN button to step through the MAX/MIN
memories.
To clear the memory, long press the MAX/MIN button while either the MAX or
the MIN mode text is showing. The memories are cleared each time the meter
power is cycled.
5.9 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.
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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