Explosion-proof range finder

Explosion-proof range finder sensor based on infra-red laser time-of-flight. This device can estimate distances to objects up to 1 or 2m, depending on conditions.

The Ex range finder is a USB distance sensor (range finder). This module is based on a "ToF" (Time of Light) technology. The sensor emits laser pulses and measures the time they take to come back to the sensor after reflection against an obstacle. The Ex range finder sensor can also measure its own temperature, in order to determine when a new calibration is required, and estimate the ambient light

The ST Microelectronics VL53L0X rangefinder sensor embedded on the Ex range finder sensor includes a 940nm infra-red VCSEL emitter, invisible to human eye, and an array of single-photon detectors. It is actually capable of detecting objects up to 1 or 2 meters, depending on the conditions, and to provide a close estimate of the nearest object distance.

This sensor has a few limitations:

• 50cm away from the sensor, the sensing zone is 20cm wide

• the max precision is 3%, inside and for clear targets

• outside and for dark objects, you should rather count on an accuracy of 6%

• the max range, inside and for clear targets, is 2m

• outside and for dark objects, the max range is typically 70cm

The device features several built-in calibration procedures to maintain the ranging accuracy while the environment changes.

Measurements can be read directly via USB or stored on the device internal flash for later retrieval when connected again by USB.

This device has been designed so that the sensor itself can be moved away from the USB part by a few meters: simply split the board into two parts and use a 4-wire cable between the two parts.

Note: To use the Ex range finder sensor in a hazardous area, the device must be protected to at least IP 65, so it must be placed inside the enclosure.

Ex range finder sensor don’t require any special drivers or software. Compatible with Windows, Mac OS, Android and Linux and easy to drive from a maximum of programming languages.

The Ex range finder sensor is connected through an industrial USB 2.0 connector to an intrinsically safe barrier Ex USB 2.0.

The Ex range finder sensor have a “hot-plug” function which allows them to be connected and disconnected without stopping, shutting down or rebooting the system.

Specifications:

USB connector: micro-B

Width: 20mm

Length: 58mm

Weight: 5g

Chipset: VL53L0X

Max accuracy: 3%

Max distance: 2m (~6%)

Field of view (FOV): 25°

Wavelength: 940nm

Laser class, according to IEC 60825: class 1

Protection class, according to IEC 61140: class III

Supported Operating Systems: Windows, Linux, Mac OS, Android

Сompliance: IP 65, RoHS

Electrical Data:

Uo=5 V

Io=50 mА

Ui=5 V

Ii=50 mА

Ci=10 µF

Ex marking:

Ex ib I Mb

Ex ib IIC T6...T4 Gb X

Ex tb IIIC T85°C...135°C Db

Produced in accordance with IEC 60079-0, IEC 60079-11, IEC 60079-31

Normal operating temperature: 5°C to 40°C

Extended operating temperature*: -20°C to 70°C

*Note: The extended temperature range is defined based on components specifications and has been tested during a limited duration (1h). When using the device in harsh environments for a long period of time, we strongly advise to run extensive tests before going to production.