Testo 477 LED Handheld Stroboscope – 30…300,000 fpm, 4800 Lux Flash, Trigger Input/Output, IP65 Aluminum Housing (0563 4770)

Testo 477 (product code 0563 4770) is an LED handheld stroboscope that makes fast-moving parts appear as if in slow motion or standing still. It operates in the range 30 … 300,000 fpm (flashes per minute) with ±0.02% accuracy and provides a flash intensity of 4800 lux at 6000 fpm at a distance of 30 cm. Rotational speed is measured without stopping machines and without the need for a reflective mark; rotation and vibration irregularities in motors, fans, pumps and turbines, and in packaging and conveyor systems, are examined during operation.

Inspection on Running Machines by Freezing Fast Motion

When the flash rate is set to the movement frequency of the part, the image freezes; when the flash rate is kept slightly below or above it, the part appears to move slowly. The flash rate is read on the display in fpm (= rpm) or Hz. Flash duration (microseconds or degrees), delay time and phase shift can be adjusted; the key lock prevents accidental changes to the settings.

Thanks to the trigger input and output, the instrument can be connected to external systems and controlled by an external signal such as a speed sensor; a pulse divider and edge selection can be used with an external trigger. Its impact-protected, IP65 aluminum housing can be wiped clean and is suitable for harsh operating conditions. With 3 × AA batteries it runs for approx. 5 hours at 6000 fpm, and approx. 11 hours with NiMH rechargeable batteries.

Technical Specifications (Official Testo Information)

• Brand / Model: Testo 477 LED stroboscope · product code 0563 4770
• Frequency Range: 30 … 300,000 fpm · accuracy ±0.02% (±1 digit) · resolution ±0.1 (30 … 999 fpm), ±1 (1000 … 300,000 fpm)
• Flash: intensity 4800 lux (6000 fpm, 30 cm) · color temperature approx. 6500 K · adjustable flash duration
• Settings: Hz unit, flash duration (µs / degrees), delay (ms), phase shift (degrees), pulse divider and edge selection (with external trigger), key lock
• Trigger Input: optocoupler · 3 … 32 V square wave, NPN + PNP · low level < 1 V · minimum pulse 50 µs · reverse polarity protected
• Trigger Output: short-circuit and overvoltage-proof transistor · NPN, max. 32 V · max. 50 mA · adjustable pulse duration
• Display: multi-line LCD
• Power Supply: 3 × AA batteries or 3 × NiMH rechargeable batteries · approx. 5 hours (batteries) / 11 hours (NiMH) at 6000 fpm
• Protection Class / Housing: IP65 · aluminum, impact-protected
• Operating Temperature: 0 … +45 °C
• Dimensions / Weight: 191 × 82 × 60 mm · approx. 400 g (including batteries)

Scope of Delivery

• Testo 477 LED stroboscope
• Connection plug for external trigger signal
• Carrying case
• Calibration protocol
• Batteries

Technician Recommendations

• Verify the actual speed with a mark: a frozen image also appears at multiples and fractions of the actual speed; on symmetrical parts such as multi-blade fans, mark one blade, start the flash rate above the expected speed and reduce it, and read the first value at which the mark gives a single, frozen image.
• Know the approximate speed: starting from an approximate value, such as the speed on the motor nameplate, speeds up finding the correct frequency.
• Use a multiple for a brighter image: the image also freezes at an exact multiple of the actual speed and appears brighter; you can carry out the inspection at this frequency.
• Do not touch the rotating part: even if the image appears to stand still, the machine is running; do not touch the parts being inspected with your hand or a tool.
• Epilepsy warning: stroboscope light can trigger epileptic seizures in susceptible people; warn the people around you.

Technical document: Testo 477 LED stroboscope product brochure (PDF, Turkish)