Triplett LD70 Laser Distance Meter

Introduction

This meter measures distance up to 70m (229.6') and calculates Area, Volume, and Indirect readings using the Pythagorean Theorem (a² + b² = c²). It also includes a laser pointer, tripod mount, and a 20-point historical data group function. For the latest version of this User Guide, Product Updates, and Customer Support, please visit www.triplett.com.

Safety Instructions

This meter has been designed for safe use but must be operated with caution.

Laser Classification (Class 2)

The meter produces a visible Class 2 laser beam from the top of the instrument.

WARNING: Do not directly view or point the laser at an eye. Do not look directly into the beam using an optical aid such as binoculars. This can create a hazard. Low power visible lasers do not normally present a hazard, but may present some potential for hazard if viewed directly for extended periods of time.

Please read all safety instructions carefully before using this instrument:

• Do not use this device in flammable or explosive environments.
• Do not use this device near aircraft or medical equipment.
• Do not use this device near strong electro-magnetic interference.
• Do not aim the meter directly into sunlight.
• Do not dis-assemble or modify the instrument.
• Do not store in areas of high temperature/humidity.
• Remove the batteries when storing the instrument for long periods.

Display Description

The display interface provides various indicators:

• 1. Laser indication: ⚡ Shows if the laser is active.
• 2. Reference edge: Indicates the measurement reference point (back edge, front edge, or tripod hole).
• 3. Indirect measurement: Icon for Pythagorean Theorem measurements.
• 4. Setting-out measurement: Icon for stake-out function.
• 5. Area/volume measurement: Icon for area/volume calculations.
• 6. Length measurement: Icon for standard distance measurement.
• 7. Battery level: ? Shows remaining battery power.
• 8. Stored data indication: Indicates stored measurement data.
• 9. Angle indication: ? Shows measured angle.
• 10. Signal strength indication: Indicates laser signal strength.
• 11. Auxiliary display area: Shows previous measurement or secondary data.
• 12. Main display area: Shows the current measurement result.

Keypad Description

The keypad includes the following controls:

• 1. Power on/measurement key: [MEAS] Turns the device on/off and initiates measurement.
• 2. Area/volume key: [Area/Volume] Selects area or volume measurement mode.
• 3. Indirect measurement key: [Indirect] Selects Pythagorean Theorem measurement modes.
• 4. "+" Key: [+] Increases value or performs addition.
• 5. Historical record key: [History] Accesses stored measurements.
• 6. "-" Key: [-] Decreases value or performs subtraction.
• 7. Reference edge key: [Reference] Selects the measurement reference point.
• 8. Clear/power off key: [CLR] Clears current input or powers off the device.
• 9. Unit key: [Unit] Switches between measurement units (feet, inch, meter).

Initial Operation and Setting

1. Install/Replace the Battery

• Open the battery cover.
• Install two AAA alkaline batteries, paying attention to polarity. Do not install reversely.
• Put the battery cover back in place.

2. Power On

Hold down the [MEAS] key for about 2 seconds to power on and enter the length (distance) measurement mode automatically.

3. Power Off

• Manual power off: Hold down the [CLR] key to power off at any mode.
• Automatic power-off: The instrument will power off automatically if there is no key operation within 46 seconds.

4. Clearing Functions

Press the [CLR] key to cancel the last instruction or clear the display.

5. Setting of the Reference Edge

The default reference edge is the back side of the instrument, with the measurement starting point at the tail end. If the reference edge is set as the front edge, the measurement starting point is the top of the instrument.

Press the [Reference] key to select the reference edge: back side, front edge, or positioning hole. The reference edge returns to the default state (back edge) after powering on the instrument again.

The positioning hole of the tripod on the back of the instrument body serves as a benchmark.

6. Setting of Function Menu

At the power-off state, hold down the [MEAS] key for about 5 seconds to enter the setting state for laser, data calibration, and buzzer.

• Laser Setting: In the interface, press [MEAS] to set the laser (the ⚡ symbol on the top left of the screen displays or disappears). The ⚡ symbol appearing indicates the laser will open automatically after powering on. The ⚡ symbol disappearing indicates it will not.
• Data Calibration: Hold down [MEAS] for about 2 seconds to enter the data calibration interface. Press [MEAS] to adjust parameters from -7mm to +7mm.
• Buzzer Setting: Hold down [MEAS] for about 2 seconds to enter the buzzer setting interface. Press [MEAS] to select on or off.

Hold down the [MEAS] key for 2 seconds to exit from the setting state.

Measurement

1. Single Measurement

In the length measurement mode, press [MEAS] to open the laser. After the laser aims at the object, press [MEAS] to carry out measurement. The measurement result is displayed in the main display area. The auxiliary display area shows the distance measured last time.

2. Continuous Measurement

This function allows users to start from one measurement point and find a distance point or measure the minimum or maximum distance (e.g., the diagonal distance or vertical distance of a room).

In the length measurement mode, hold down [MEAS] to enter continuous measurement mode; the buzzer sounds. The auxiliary display area shows the measured maximum value (MAX) and minimum value (MIN). The main display area shows the currently measured distance. Press [CLR] to exit continuous measurement mode.

3. Area Measurement

Press [Area/Volume] key once. The screen displays an icon indicating the edge to be measured, which flashes to prompt. Press [MEAS] key to complete measurement of length and width respectively; the instrument calculates the area automatically.

4. Volume Measurement

Press [Area/Volume] key twice. The screen displays an icon indicating the edge to be measured, which flashes to prompt. Press [MEAS] key to complete measurement of length, width, and height respectively; the instrument calculates the volume automatically.

5. Accumulation/Subtraction Function

For distance, area, and volume measurements, accumulation (addition) or subtraction operations can be performed.

• Press [+] key for additive operation and [-] key for subtraction.
• Distance Accumulation/Subtraction: In length measurement mode, press [MEAS] to measure and obtain a distance. For addition, press [+] and the screen displays "+". For subtraction, press [-] and the screen displays "-". Press [MEAS] again to measure the distance to be added (or subtracted). The result is displayed in the main display area.
• Area/Volume Accumulation/Subtraction: In area/volume measurement mode, perform the initial measurement. For addition, press [+] and the screen displays "+". For subtraction, press [-] and the screen displays "-". Press [MEAS] key to measure and obtain the area/volume to be added (or subtracted). Finally, press [MEAS] key again; the result is displayed in the main display area.

6. Indirect Measurement with Pythagorean Theorem

This function calculates missing sides of a right-angled triangle.

• Scenario 1: Measure the bottom edge (b) and hypotenuse (c) to calculate the height (a).

Diagram: A right-angled triangle with sides labeled 'a' (height), 'b' (base), 'c' (hypotenuse). Formula: a = √(c² - b²).

At the length measurement mode, press [Indirect] once. The screen displays an icon indicating the edge to be measured, which flashes to prompt. Press [MEAS] key to complete measurement of hypotenuse 'c' and right-angle side 'b'. The instrument calculates the height 'a' automatically.

Note: When measuring the bottom edge 'b', keep the instrument horizontal.

• Scenario 2: Measure hypotenuse 'a', hypotenuse 'c', and common right-angle edge 'b' to calculate the length of edge 'd'.

Diagram: A triangle with sides 'a', 'b', 'c', 'd'. 'b' is the common right-angle edge. Formula: d = √(a² - b²) or d = √(c² - b²).

At the length measurement mode, press [Indirect] key twice. The screen displays an icon indicating the edge to be measured, which flashes to prompt. Press [MEAS] key to complete measurement of hypotenuse 'a', hypotenuse 'c', and common right-angle side 'b'. The instrument calculates the length of edge 'd' automatically.

Note: When measuring the common right-angle side 'b', keep the instrument horizontal.

• Scenario 3: Measure hypotenuse 'a', hypotenuse 'b', and common right-angle edge 'c' to calculate the length of edge 'd'.

Diagram: A triangle with sides 'a', 'b', 'c', 'd'. 'c' is the common right-angle edge. Formula: d = √(a² - c²) or d = √(b² - c²).

In the length measurement mode, press [Indirect] key three times. The screen displays an icon indicating the edge to be measured, which flashes to prompt. Press [MEAS] key to complete measurement of hypotenuse 'a', hypotenuse 'b', and common right-angle side 'c'. The instrument calculates the length of edge 'd' automatically.

Note: When measuring the common right-angle side 'c', keep the instrument horizontal.

7. Angle Measurement Function

When the angle and length of the hypotenuse are known, calculate the length of right-angle sides 'a' and 'b'.

Diagram: A right-angled triangle with sides 'a', 'b', and hypotenuse. An angle indicator shows 90°.

Measurement Condition

Measurement results may have significant errors under conditions such as extremely strong sunshine, large temperature fluctuations, or weak reflector reflection. The effect will be better if an objective reflect sheet is used under such conditions.

When measuring objects that are colorless liquids (like water), clean glass, or have transparent surfaces, mistaken measurements may occur. When measured objects reflect light strongly, the laser may be reflected, leading to mistaken measurements. When measuring surfaces without reflection or very dark surfaces, the measurement time increases, or an error may be reported. In such conditions, use the objective reflector sheet.

Product Maintenance

• Do not place the instrument in high temperature and high humidity environments for storage.
• If the instrument is not in use for a long time, remove the batteries to prevent corrosion from battery leakage.
• Keep the instrument clean. Use a soft, wet cloth to wipe the instrument shell. Use a cleanser for optical lenses to wipe the sensor lens and screen. Do not use corrosive cleansers.

Failure Prompt

Technical Parameters