Choose an H-Series Rangefinder by Operating Point

The H-series is not a six-step ladder where the largest headline distance automatically makes the best choice. A usable choice starts with the surface condition at the real working distance, then checks how each model reports, how it connects to the host and what the rail can provide. The result is usually clear before the comparison reaches the catalogue maximum.

Start with the surface, not the headline range

Each published range line contains two conditions. The first is at 90% reflectivity; the second is the lower-reflectance figure. Treat them as two separate selection checks, not one continuous range. A system intended to see a dark, weathered or otherwise less reflective surface must clear the second figure at its required distance. A bright reference target does not prove that it will.

The table answers a practical question that the model names do not: what must still be true when the target is less cooperative? For example, the 200 m row publishes 70 m for that second condition. Selecting it solely because “200 m” is larger than the required distance ignores the condition carried by the other number.

Do not merge the two reporting descriptions

There are two distinctly worded groups. LRF50H, LRF100H and LRF200H publish a 20 Hz-10 kHz range with 1 kHz as the default. LRF300H, LRF600H and LRF1500H instead publish two values, 1 kHz or 50 Hz, with automatic selection to match echo strength. The latter statement is not a published continuous setting range down to 20 Hz, and the former statement is not a promise that every return will arrive at a fixed host interval.

This distinction matters when software has a deadline rather than just a desire for more samples. Put the acceptable age of a measurement in the system requirement, then evaluate the model’s stated reporting behaviour and the full host path: transport, parser, queueing and control loop. Do not turn a nominal frequency into an unattended timing guarantee.

The step from the 200 m row to the 300 m row also changes the documented average-power figure from 0.7 W to 1.2 W. That is a comparison fact, not proof that reporting behaviour causes the power change. The rail still has to be designed for the named module and the deployed configuration.

Interface can decide the result before optics does

LRF50H is published with UART. The other five named models publish UART / I²C. If the controller has no spare UART and the design depends on the two-wire interface, the 50 m model is not an equivalent replacement merely because its range is otherwise sufficient. Conversely, a host using UART can keep that option through all six entries.

All six documents list a 9-36 V DC module supply, but none of that common supply statement establishes the voltage levels on UART signal pins. Do not derive a signal-level value from the power-input range. Confirm that item from the current model documentation or engineering before wiring a host.

A five-step selection record

1. Write the farthest required distance and the actual target condition. Check it first against the relevant lower-reflectance range, then record the 90% reflectivity figure separately. If either condition is being substituted for a project-specific target, mark that as a test item rather than an accepted result.
2. Write the oldest measurement your controller can accept. Keep the 20 Hz-10 kHz default-1-kHz group separate from the 1 kHz-or-50-Hz automatic-switching group; do not turn either specification into a fixed interval promise.
3. Check the host ports. Select LRF50H only where a UART-only interface fits; if I²C is required, retain LRF100H, LRF200H, LRF300H, LRF600H or LRF1500H as the applicable group.
4. Reserve the published average power for the selected model on the supply budget: 0.8 W for LRF50H, 0.7 W for LRF100H or LRF200H, and 1.2 W for LRF300H, LRF600H or LRF1500H. Then confirm the complete rail design against the released hardware information.
5. Before software freeze, confirm the specific model’s current protocol and pin details. The LRF1500H manual contains registered internal conflicts concerning its out-of-range notation and wider-frame checksum example, so that model needs engineering confirmation rather than an assumed parser rule.

When the 1500 m entry remains in scope

LRF1500H is the only row here that publishes a 0.05-300 m lower-reflectance range. Verify its out-of-range value format and the checksum over the three distance bytes against frames captured from the delivered unit; ERDI engineering confirms both in writing before an integration freezes the parser.

For a long-range comparison that also distinguishes the different LRF3000A1 family and its protocol, see the 300-3000 m module comparison. For the nearby end of any selection, the minimum measuring distance guide explains why a stated maximum range does not remove the need to check the close-in boundary. The model pages retain the current public parameter cards.

For a public reference on documenting measurement results with their conditions and uncertainty, see NIST Technical Note 1297. It is a useful discipline here: preserve the reflectance condition and the reporting description beside every number instead of carrying a maximum value alone.

Send the working distance, target surface, update requirement and host interface to https://erdilrf.com/contact/. We can check the documented operating point and identify the configuration items that still require engineering confirmation.

Category pages: 100 m laser distance sensor · Laser rangefinder module

Models mentioned in this article

• LRF1500H905 nm · up to 1.5 km · UART · I2C · 20 ± 2 g
  From $250 · shipping includedSee price & buy
• LRF50H905 nm · up to 50 m · UART · 15 ± 2 g
  From $80 · shipping includedSee price & buy
• LRF100H905 nm · up to 100 m · UART · I2C · 20 ± 2 g
  From $140 · shipping includedSee price & buy
• LRF200H905 nm · up to 200 m · UART · I2C · 20 ± 2 g
  From $150 · shipping includedSee price & buy