EXTECH 461825

User’s Guide
Combination Photo-Tachometer Stroboscope
Model 461825
Introduction
Congratulations on your purchase of Extech’s Combination PhotoTachometer/Stroboscope. This professional meter, with proper care, will provide
years of safe reliable service.
Meter Description
1
1.
2.
3.
4.
5.
6.
7.
8.
Tachometer Light Source
LCD Display
Measure trigger button
Memory Recall button
FINE adjust knob
COARSE adjust knob
Range/Function select switch
Stroboscope flash tube
2
3
4
Note: Battery compartment is on rear of
meter
5
6
7
8
2
461825 Ver. 1.2 03/05
Operation
STROBOSCOPE MEASUREMENT PROCEDURE
Select the Stroboscope Function and Range using the Range/Function Select
Switch. The switch has four positions, three of which are stroboscope-dedicated
with white range numbers. The fourth position is Photo-Tachometer dedicated
and is labeled as such.
Speed Measurements.
1. Remove power to the moving object under test and affix a target mark on
the area to be measured.
2. Apply power to the moving object and press the stroboscope's Measure
Trigger Button.
3. Aim the Stroboscope light beam toward the marked area on the object
under test.
4. Use the FINE and COARSE adjust knobs to synchronize or "stop" the
motion of the object's mark. A single stationary image of the mark
provides actual speed measurement data.
NOTE: Care must be taken to ensure that the mark is providing a 1:1
measurement. This is done by checking that there is only one mark and not two,
four, or more stationary marks on the object under test. Two or more stopped
marks indicate "harmonic" measurements (2:1, 3:1, 4;1 etc.) which provide a
doubling, tripling, or quadrupling of the actual speed. A useful method of
avoiding harmonic measurements is to adjust the FINE/COARSE knobs until
two images (marks) appear and then lower the flash rate (via COARSE/FINE
knobs) until a single, stationary image appears. This is the actual speed.
Inspecting a moving object.
Measure the speed of a moving object as described above and move the FINE
adjust knob alternately higher and lower to visually inspect all areas of the
device.
3
461825 Ver. 1.2 03/05
PHOTO-TACHOMETER MEASUREMENT PROCEDURE
1.
2.
3.
4.
5.
Select the Photo-Tachometer function by moving the Range/Function
select switch to the PHOTO position.
Affix a small piece (approx. 0.5") of supplied reflective tape to the
object under test.
Press the meter's Measurement Trigger button and align the PhotoTachometer light source with the reflective tape mark on the moving
object.
Wait until the Monitor Indicator appears in the upper left hand corner of
the LCD indicating that synchronization has occurred.
Release the Measure Trigger button only after the reading has
stabilized (approx. 2 seconds).
NOTE: To obtain better accuracy for low RPM measurements (less than 50
RPM) use more than one piece of reflective tape. Divide the meter reading by
the number of reflective tape pieces for accurate measurement data.
MEMORY RECORD AND RECALL
The 461825 can record Maximum, Minimum, and Last Reading for the period of
time during which the Measure Trigger button is held. These stored values can
then be read directly on the meter's display. The memory will automatically
erase after approximately 10 seconds of meter inactivity. Access the memory
data immediately after the measurements.
1.
2.
3.
4.
5.
Follow the instructions for normal operation.
Release the Measurement Trigger button.
Immediately press the Memory Recall button once to display the Last
Reading taken during the measurement period. 'LA' will alternately
display with the data reading to indicate 'Last Reading".
Release and press the Memory Recall button again to display the
Maximum reading taken during the measurement period. 'UP' will
alternately appear with the data reading to indicate Max. reading.
Release and press the Memory Recall button again to display the
Minimum reading taken during the 30 second test period. 'dn' will
alternately appear with the data reading to indicate Min. reading.
4
461825 Ver. 1.2 03/05
Specifications
General Specifications
Circuit
Display
Measurement
units
Memory Recall
Operating
Temperature
Operating
Humidity
Power Supply
Weight
Dimensions
Accessories
Custom LSI microprocessor based design
Reversible, 0.4" (10mm) 5-digit (99999 count) LCD display
RPM (revolutions or rotations per minute)
Records/Recalls Max/Min/Last readings with memory pushbutton
32 to 122oF (0 to 50oC)
< 80% RH
Four 1.5V 'AA" batteries (UM-3 or equivalent)
0.66 lb. (300g)
8.5x2.6x1.5" (215x65x38mm)
Reflective tape and carrying case
Electrical Specifications
Measurement Range
Resolution
Accuracy
Sampling Time
Photo Tachometer detection
distance
Stroboscopic Flash rate
Stroboscopic Flash adjust
range
Stroboscopic Flash tube type
Stroboscopic Flash duration
Stroboscopic Flash Color
5 to 99,999 RPM for the Tachometer
100 to 100,000 FPM/RPM for the
Stroboscope
0.1 RPM (<1000 RPM) and 1 RPM (> 1000
RPM)
± (0.1% + 2 digits)
1 second (> 60 RPM)
2 to 6" (50 to 150mm) typical
Note: Detection distances up to 12"
(300mm) are possible depending upon
ambient light
100 to 100,000 FPM (flashes per minute)
Range A: 100 to 1,000 FPM
Range B: 1000 to 10,000 FPM
Range C: 10,000 to 100,000 FPM
High efficiency LED lamp
60 to 1000 microseconds (approx. 16% of
period)
Orange
5
461825 Ver. 1.2 03/05
Warranty
EXTECH INSTRUMENTS CORPORATION warrants this instrument to be free
of defects in parts and workmanship for one year from date of shipment (a six
month limited warranty applies to sensors and cables). If it should become
necessary to return the instrument for service during or beyond the warranty
period, contact the Customer Service Department at (781) 890-7440 ext. 210 for
authorization or visit our website www.extech.com for contact information. A
Return Authorization (RA) number must be issued before any product is returned
to Extech. The sender is responsible for shipping charges, freight, insurance and
proper packaging to prevent damage in transit. This warranty does not apply to
defects resulting from action of the user such as misuse, improper wiring,
operation outside of specification, improper maintenance or repair, or
unauthorized modification. Extech specifically disclaims any implied warranties
or merchantability or fitness for a specific purpose and will not be liable for any
direct, indirect, incidental or consequential damages. Extech's total liability is
limited to repair or replacement of the product. The warranty set forth above is
inclusive and no other warranty, whether written or oral, is expressed or implied.
Calibration and Repair Services
Extech offers repair and calibration services for the products we sell. Extech
also provides NIST certification for most products. Call the Customer Service
Department for information on calibration services available for this product.
Extech recommends that annual calibrations be performed to verify meter
performance and accuracy.
Support line (781) 890-7440
Technical support: Extension 200; E-mail: [email protected]
Repair & Returns: Extension 210; E-mail: [email protected]
Product specifications subject to change without notice
For the latest version of this User’s Guide, Software updates, and other
up-to-the-minute product information, visit our website: www.extech.com
Extech Instruments Corporation, 285 Bear Hill Rd., Waltham, MA 02451
Copyright © 2005 Extech Instruments Corporation
All rights reserved including the right of reproduction in whole or in part in any form.
6
461825 Ver. 1.2 03/05