Eddy current displacement sensor for homing and surface scanning in 3D printers.

Works with Kalico and Klipper. Ships fully assembled and includes a USB cable.

WARNING: Requires a conductive surface or substrate on the printer bed to work. Bed stacks that include oversized fixed magnets are not recommended and may not work with Beacon. BTT Pi and BTT Manta are known to cause damage to Beacon devices, and must be used with an inline hub or a different SBC.

Eddy Current Surface Scanner for 3D Printers

• Native displacement output: no Z motion necessary for sensing
• Scan mode mesh: dense grid sampling in a matter of seconds
• Low thermal drift: minimized by design, with active compensation for everything else

Rev H

Rev H adds a high temperature rated accelerometer, so resonance testing and input shaping run from the probe with no ADXL to mount and remove, measuring up to 100C and surviving standby to 115C. The sensitivity and thermal drift figures in the table below are relative improvements rather than absolute measurements.

Contact Mode

Contact is one of two probing modes, alongside proximity, the non-contact scanning the probe is better known for. The nozzle physically touches the bed and the sensor detects the moment its own Z motion is interrupted, with no switch or moving parts. Either mode can be selected per command or set as the config default.

Contact handles automatic Z offset and model calibration, and placed in a print start macro it recalibrates on every print, so nozzle and plate changes stop mattering. It is also immune to fixed magnets and to metallurgical variation in the plate, meaning beds that scan mode cannot read are often still workable. Full details are in the Beacon contact documentation.

Printer Compatibility

• Firmware: Kalico and Klipper
• Connection: USB to single board computer
• Bed: conductive surface or substrate, 400um or thicker. Bare steel, WHAM BAM, PEI coated or laminated steel, and similar. Use with beds employing large or oversized fixed magnets is not recommended.

Includes

• 1x Beacon board (main PCB, sensing PCB, headers, cable connector)
• 1x custom USB cable (6ft free, or 10.5ft for an additional fee)

Variations

• Normal: best for Annex or StealthBurner printers
• Normal: main PCB and sensing PCB are assembled flat
• Low-Profile: best for VzBot, RatRig, or K3 Frostbite printers
• Low-Profile: main PCB and sensing PCB are assembled flat, as is the cable connector

Warranty

• 30-day standard warranty, following the date of delivery
• Using a BTT Pi or BTT Manta board with the Beacon without an inline hub voids the warranty

Additional Information

Variation Normal, Low Profile

Cable Length 6ft, 10.5ft

Size 38mm x 27.5mm

Form-Factor Planar

Weight 3.3 grams

Bandwidth 1kHz

Resolution 0.5 um

Temperature Rating 115C sensor, 115C amplifier

Sensitivity +20%

Thermal Drift -40%

Coil Material Improved performance and durability

Accelerometer Fully rated (100/120C)

Probing Modes Proximity (scan) and contact

Firmware Kalico and Klipper

Device ID Enumerates as Beacon_RevH under /dev/serial/by-id/

Data Link USB (cable included)

Input Protection Improved ESD and reverse polarity

Bed Material Conductive surface or substrate, 400um or thicker. Bare steel, WHAM BAM, PEI coated or laminated steel, and similar.