digital protractor with large digital display, length 500 mm, accuracy ±0.3 degrees, hinge mechanism on angle scale allows measurement of inside and outside angles and reverse angles from 0 to 360°. Angle and ruler combined into one digital display angle ruler with locking function, which can be locked at any angle, turn the locking knob clockwise, and turn it counterclockwise to loosen the knob.
||3V CR2032 * 1 grain, life more than 2000 hours
||Color card + blister package
|Weight with Packaging
- Digital angle finder protractor with digital display, easy to read.
- Digital angle protractor with data lock function.
- Unit conversion, decimal part in degrees, and minutes switching.
- The 2 in 1 digital protractor has both angle measurement and metric length measurement functions for measuring the internal and external angles of workpieces.
- The reliable locking function allows you to lock the angle at any desired position.
- Turn clockwise to release the knob.
- Drawer-type battery compartment for easy battery replacement.
- Use 3V CR2032 button cell battery, service life over 2000 hours, negative pole facing up, positive pole facing down when installing the battery.
Tips: How to calibrate a digital protractor?
1. Working flatness
When measuring the flatness of the working surface of the inclinometer, it is recommended to use a knife-edge ruler and a gauge block for measurement. The knife-edge ruler is close to the working surface, and the gap between them is observed or measured with a gauge block. The measured value is the measurement result. Measurements should be made in at least 3 directions of the working surface. The working surface should be convex, and the flatness of the working surface should be less than 0.005mm.
2. Indication stability of digital display
The measurement starts after the device is turned on and warmed up. Observe once every 15 minutes, and take the difference between the maximum value and the minimum value in one hour as the stability result of the digital display.
3. Indication of repeatability
Under the same measurement conditions, the four positions of 0°, 90°, 180°, and 360° of the inclinometer are read 5 times respectively, and the difference between the maximum and minimum readings at each position is the repeatability of the indication at this position. The indication repeatability of the instrument is determined by the maximum value of the indication repeatability among the four positions.
4. Indication error
The indication error of the inclinometer can be measured with a high-precision horizontal dividing head or can be measured with a 0-level triangular square or cylindrical square and a sine gauge.