Datasheet

Page 3

Web: www.maxbotix.com

PD11500c

MaxBotix

Inc.

Patent 7,679,996

HRXL-MaxSonar

WR/WRC

™

Series

MaxBotix Inc., products are engineered and assembled in the USA.

Auto Calibration

Each time the HRXL-MaxSonar-WR takes a range reading, it calibrates itself. The sensor then uses this data to range

objects. If the temperature, humidity, or applied voltage changes during sensor operation, the sensor will continue to

function normally over the rated temperature range while applying compensation for changes caused by temperature and

voltage.

Sensor Operation: Free-Run

When operating in free run mode, the HRXL-MaxSonar-WR sensors are designed to be used in a variety of outdoor,

industrial, or indoor environments. Many acoustic noise sources will have little to no effect on the reported range of the

HRXL-MaxSonar-WR sensors. Most range readings are accurately reported. If the range readings are affected, the effect

is typically less than 5-mm

. This allows users to employ real-time ultrasonic distance sensing without the need for

additional supporting circuitry or complicated user software.

Sensor minimum distance - No Sensor Dead Zone

The sensor minimum reported distance is 30-cm (11.8 inches). However, the HRXL-MaxSonar-WR will report targets up

to the sensor face (for the WR sensors)

and to within 1-mm of the front sensor face (for the WRC sensors)

. Targets

closer than 300-mm will typically range as 300-mm.

Sensor Operation from 30-cm to 50-cm

Because of acoustic phase effects in the near field, objects between 30-cm and 50-cm may experience acoustic phase

cancellation of the returning waveform resulting in inaccuracies of up to 5-mm. These effects become less prevalent as the

target distance increases, and have not been observed past 50-cm. For this reason, users that require the highest sensor

accuracy are encouraged to mount the HRXL-MaxSonar-WR farther than 50-cm away from objects.

Range “0” location

The HRXL-MaxSonar-WR reports the range to distant targets starting from where the threading and nut meet on the

sensor housing as shown in the diagram below.

In general, the HRXL-MaxSonar-WR will report the range to the leading edge of the closest detectable object. Target

detection has been characterized in the sensor beam patterns.

Notes:

Refer to section that compares WR to WRC on page 11