Extech Instruments 461830 User manual

User Manual
Digital Stroboscope Tachometer
Model 461830 and Model 461831
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Introduction
Congratulations on your purchase of the Extech Digital Stroboscope Tachometer. This device
measures the speed of moving parts such as gears, fans, propellers, centrifuges, and pumps. The
stop-motion action of this instrument permits the visual inspection of moving parts. Careful use of
this instrument will provide years of reliable service.
Safety
This symbol, adjacent to another symbol or terminal, indicates the user must refer to the
manual for further information.
This symbol, adjacent to a terminal indicates that, under normal use, hazardous voltages
may be present
WARNING: Do not look directly at the Strobe eflector.
WARNING: This device causes moving objects to appear still. Take precautions against accidental
contact with moving objects.
CAUTION: Do not touch the flash tube.
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Specifications
General Specifications
Circuit Exclusive one-chip LSI circuit with crystal time base
Display 4-digit (10,000 count; 0 to 9999) LED display
Measurement unit RPM (revolutions or rotations per minute) is the speed of the
moving device under test which equals the FPM rate (strobe
flashes per minute)
Operating Temperature 32 to 122oF (0 to 50oC)
Operating Humidity < 80% RH
Power Supply 110VAC (461830) or 220VAC (461831) 50/60Hz ±10%
Power Consumption <25 watts @ 115V
Weight 1kg (2.2 lbs.)
Dimensions 21 x 12 x 12cm (8.3 x 4.8 x 4.8")
Housing construction Impact resistant plastic with plastic l
ens and mirrored reflectors
Electrical Specifications
Measurement Range 100 to 10,000 RPM/FPM
Resolution 0.1 (<1000 RPM/FPM)
1 (1000 to 9999 RPM/FPM)
10 (10,000 RPM/FPM)
Accuracy ± (0.05% + 1 digits)
Sampling Time 1 second
Strobe Flash adjust range LOW: 100 to 1,000 RPM/FPM
HIGH: 1000 to 10,000 RPM/FPM
Strobe Flash tube type Xenon lamp
Strobe Flash duration 60 to 1000 microseconds
Strobe Flash Energy 4 Watt-Seconds (Joules)
Strobe Beam Angle 80o
Strobe Flash Color White 6500oK
Notes: Replace the Xenon lamp when readings appear irregular. To prolong the Xenon lamp life and
ensure safe operation, please adhere to the following recommendations.
A 30-minute use limit < 3000rpm and 5-minute use limit > 3000rpm exists. Do not use the
instrument for periods longer than specified otherwise damage to the instrument may result.
Always permit a 10-minute cool-down between cycles.
Do not touch the Xenon flash tube.
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Meter Description
1. Xenon lamp
2. LED Display
3. Grip handle
4.
COARSE adjust knob
5. FINE adjust knob
6. Power ON/OFF switch
7. Range Select Switch
8. AC power cord and jack
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Operation
Powering the instrument
1. Plug the supplied power cable into the instrument power cable jack.
2. Plug the other end of the cable into an appropriate AC power source. The Model 461830
requires 110VAC and the 461831 requires 220VAC. Do not plug the device into an incorrect
power source otherwise damage to the instrument will result.
3. Use the ON/OFF switch to turn the instrument on or off.
Speed (RPM) Measurements
1. Remove power to the device under test so that it is stationary.
2. Affix a mark or place a small piece of the tape on the device under test.
3. P
4.
5. Read the RPM value on the LED display.
Range Adjustments
1. While measuring, use the RANGE button to select the range as desired
2. The LOW range is used for measurements below 1,000 RPM. The HIGH range is used for
measurements above 1,000 RPM.
Visually inspecting a moving object (stop-motion)
When the speed of the moving object matches the flash rate of the stroboscope, the moving object
appears still. Measure the speed of a moving object as described in the previous sections to obtain
a stop-motion. Once stop-motion is achieved, the FINE adjust knob is used to vary the viewing
perspective of the object under test for visual inspection.
Important note on Test Durations
The Xenon lamp used in this instrument has time restrictions on usage. If the specified test times
and cool-off periods (shown in the table below) are not observed, damage to the instrument can
result and the life span of the lamp can be shortened.
RPM Max. Operating Time Cool-Off Time
< 3,000 rpm 30 minutes 10 minutes
> 3,000 rpm 5 minutes
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Notes on Speed Measurements
Care must be taken to ensure that the mark is providing a 1:1 measurement. Check that there is
only one mark and not two, four, or more stationary marks on the object under test.
instrument will display double, triple, or quadruple 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
will be the actual speed.
In the example below, a rotating shaft is affixed with one piece of tape. The illustrations below
represent several possible images that would appear when the strobe beam is pointed to the shaft.
If more than one mark appears (as i
The bold column (column 2) shows the actual speed of the shaft. Column 1 shows a harmonic
-between (Column 2 in bold).
Shaft speed 1000rpm 1000rpm 1000rpm 1000rpm 1000rpm
Strobe flash rate 500rpm 1000rpm 2000rpm 3000rpm 4000rpm
Visible marks 1 12 3 4
Note that the LED display has an AUTO RANGE INDICATOR (flashing decimal at the far right) that
appears when the readings are over 10,000 RPM. In these cases, multiply the displayed reading by
10.
Copyright ©2013-2018 FLIR Systems, Inc.
All rights reserved including the right of reproduction in whole or in part in any form
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