User's Guide Model 461920 Laser Photo Tachometer
Introduction Congratulations on your purchase of Extech's Mini Laser Photo Tachometer, Model 461920. This Tachometer provides non-contact RPM and Revolution count measurements. The laser pointer beam provides accurate long distance measurements for photo tachometer measurements. This meter is shipped fully tested and calibrated and, with proper use, will provide years of reliable service. Meter Description 1. Photo Tachometer sensor and laser source 2. MEASURE button 3. MEMORY button 4. MODE button 5.
Meter Operation 1. Apply an appropriately (0.5”/12mm) sized square piece of reflective tape to the surface of the object under test. 2. Point the meter toward the device under test at a distance of 2" to 20" (50 to 500mm). 3. Press the Measure button (MEAS) and align the laser light beam with the reflective tape. 4. Verify that the ((( ))) Monitor Indicator appears on the LCD when the reflective tape passes through the light beam. 5.
Specifications Time base Display Laser light source Detecting Distance Sampling Time Tachometer accuracy Memory Operating Conditions Power Supply Power Consumption Weight Size Quartz crystal 5 digit LCD display Class 2 laser < 1mW power; Wavelength is 630 to 670nm 2 to 20" (50 to 500 mm) 0.5sec (over 120 rpm) ± (0.05% reading + 1digit) Last reading and MIN/MAX readings 32 °F to 122 °F (0 °C to 50 °C); RH 80% Max Internal 9V battery or external AC Adaptor (6 to 9VDC) 45mA DC approx. 5.3oz. (151g) 6.3x2.3x1.
Battery Replacement The low battery indication appears as “ " on the display. To replace the batteries, loosen the two Philips head screws securing the rear battery cover and lift the cover off. Replace the 9V battery and replace cover.
