Extech Instruments 461995 User manual

User's Manual
Model 461995
Laser Photo / Contact Tachometer
Laser
Photo/ Contact
PHOTO CONTACT
m / min ft / min
rpm
MEMORY
461995
Tachometer
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Extech 461995 Combination Contact Laser Photo Tachometer
Extech 461995-NIST Combination Contact Laser Photo Tachometer

461995-EU-EN v1.5 07/13
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Introduction
Congratulations on your purchase of Extech's Laser Photo/Contact Tachometer, Model 461995.
This Tachometer provides contact/non-contact RPM and Linear Surface Speed measurements. The
laser pointer beam provides accurate long distance measurements for photo tachometer
measurements. This meter, with proper care, will provide years of safe reliable service.
Safety
1. Use extreme caution when the laser beam is on
2. Do not point the beam toward anyone's eye
3. Be careful not to let the beam strike the eye from a reflective surface
4. Do not use the laser near explosive gases or in other potentially explosive areas
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461995-EU-EN v1.5 07/13
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Meter Description
1. Photo Tachometer sensor and laser source
2. LCD
display
3. MEMORY button
4. Function
switch
5. Contact tachometer rotating ring
6. MEASURE
button
7. Battery compartment (rear)
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461995-EU-EN v1.5 07/13
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Meter Operation
Reversible LCD Display
The 461995 LCD display indicates Photo Tachometer measurements in one direction and Contact
measurements in the opposite direction. This permits the user to easily read the measurement digits
in both measurement modes with the meter held in either direction.
Photo Tachometer Measurements (refer to diagram below)
1. Apply an appropriately sized square piece of reflective tape to the surface of the object under
test.
2. Move the Function switch to the PHOTO position.
3. Point the laser pointer end of the meter toward the device under test at a distance of 2" to 79"
(50 to 2000mm).
4. Press the Measure button (located on the right side of the meter) and align the laser pointer
beam with the reflective tape.
5. Verify that the Monitor Indicator appears on the upper left hand section of the LCD when the
object under test passes through the light beam.
6. Release the Measure button when the RPM reading stabilizes on the LCD.
7. If the rpm is under 50,apply additional squares of reflective tape. Divide the reading shown on
the display by the number of pieces of reflective tape squares to calculate the actual rpm.
NOTE: Bright ambient light may interfere with the reflected light beam. Shading the target area may
be necessary in some cases.
CAUTION: Rotating objects can be dangerous. Use extreme care.
Photo Tachometer
Rotating object
Reflective tape
Light source
and reflection
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461995-EU-EN v1.5 07/13
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Contact Tachometer RPM Measurements
1. Move the Function switch to the CONTACT position.
2. Press the Measure button while lightly pressing the rotating ring against the center opening
of a rotating shaft.
3. Release the Measure button when the display stabilizes (approx. 2 seconds).
Linear Surface Speed (ft/min or m/min) Measurements
1. Slide the Function Switch to "SURFACE SPEED ft/min" or "m/min" position.
2. Install the surface speed attachment on the meter rotating ring.
3. Press the Measure button and hold the surface speed wheel against the device being
measured.
4. Release the Measure button when the display stabilizes (approx. 2 seconds).
MIN/MAX and Last Reading Memory Recall
The 461995 can record Maximum, Minimum, and Last Reading for the period of time the Measure
button is held. These stored values can then be read directly on the meter's display. The memory
will automatically clear after approximately 10 seconds of meter inactivity. Access the memory data
immediately after the measurements have been taken as follows:
1. Press the Memory key once and hold it down: The Last Reading is displayed followed by the
"LA" icon.
2. Press again and hold: The Maximum value is displayed followed by the "UP" icon
3. Press again and hold: The Minimum value is displayed followed by the "dn" icon
Battery Replacement
The low battery indication appears as "LO" on the display. To replace the batteries, slide the rear
battery compartment cover off of the meter, replace the four 1.5V AA batteries, and replace cover.
You, as the end user, are legally bound (EU Battery ordinance) to return all used
batteries, disposal in the household garbage is prohibited! You can hand over your
used batteries / accumulators at collection points in your community or wherever batteries
/ accumulators are sold!
Disposal: Follow the valid legal stipulations in respect of the disposal of the device at the
end of its lifecycle
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461995-EU-EN v1.5 07/13
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Specifications
General Specifications
Circuit Custom one-chip LSI microprocessor circuit
Time base Quartz crystal 4.194 MHz
Display Reversible 5 digit 0. 10mm (4") LCD display
Laser light source Less than 1mW; Class 2 red laser diode (645nm approx.)
Detecting Distance 50 to 2000 mm (2 to 79") depending on ambient light and RPM
Memory Last reading and MIN/MAX readings
Operating Conditions 0 °C to 50 °C (32 °F to 122 °F); RH 80% Max
Power Supply 4 x 1.5 V AA batteries
Power Consumption 20mA DC approx.
Weight 300g (10.6oz) including battery)
Size 210 x 67 x 38 mm (8.5 x 2.6 x 1.5")
Accessories (4) x 1.5V batteries, reflective tape 600mm (24"), surface
speed/rpm rotating attachments, and carrying case
Range Specifications
Range Resolution Accuracy (%rdg)
Photo
Tachometer
10 to 99,999 rpm 0.1 rpm (<1000rpm)
1 rpm (>1000 rpm)
± (0.05% + 1d)
Contact
Tachometer
0.5 to 19,999 rpm 0.1 rpm (<1000rpm)
1 rpm (>1000 rpm)
Surface
Speed
0.2 to 6560 ft/min 0.1 ft/min (<1000ft/min)
1 ft/min (>1000ft/min)
± (1% + 1d)
Surface
Speed
0.05 to 1999.9 m/min 0.01 m/min (<100m/min)
0.1 m/min (>100 m/min)
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