• Assembly Instructions
  • Step 1: Gather the parts and tools
  • Step 2: Install the moisture sensor
  • Step 3: Install the Magnets
  • Step 4: Install the Electrical Screws
  • Step 5: Add the Jumper Wire

This single 3D printable component magnetically mounts onto FarmBot’s UTM like any other tool. It works by driving the tool vertically into the soil so that the soil properties can be accurately read.

Assembly Instructions

20 minutes

This is the estimated time it will take to assemble the soil sensor.

Step 1: Gather the parts and tools

Gather all the soil sensor parts from the table below and lay them out in a logical manner. To complete the assembly, you will also need the following tools:

• 2mm hex (allen) driver
• 3mm hex (allen) driver
• 6mm wrench
• 8mm wrench
• Wire strippers

Qty.	Component
1	Soil Sensor Base
1	Moisture Sensor
3	Ring Magnets (15 x 15 x 5mm)
3	M5 x 25mm Screws
3	M5 Locknuts
2	M3 x 10mm Screws
4	M3 x 16mm Screws
6	M3 Locknuts
1	Jumper Wire (18 guage, 30mm length)
4	Zipties

Step 2: Install the moisture sensor

Attach the moisture sensor to the soil sensor base using two M3 x 10mm screws and M3 locknuts. The sensor should be on the front side of the base’s mounting tabs. The heads of the screws should be on the sensor (front) side while the locknuts should be on the mounting tabs (back) side. Do not overtighten the screws as this could damage the soil sensor circuit board.

Step 3: Install the Magnets

Opposites attract

For the soil sensor to correctly mount to the UTM, all magnets on the soil sensor must be attracted to the magnets in the UTM.

To find the correct orientation for a soil sensor magnet, hold it near the mounting side of the UTM. Flip it around in your hand until you feel it attracting to the UTM’s magnets. This is the correct orientation for mounting to the soil sensor base.

Secure the three ring magnets to the top of the soil sensor base using three M5 x 25mm screws and M5 locknuts. The screw head should be on the magnet side of the soil sensor base. Use the 3mm hex driver and 8mm wrench to tighten the components.

Step 4: Install the Electrical Screws

Use the 2mm hex driver and 6mm wrench to attach two M3 x 16mm screws and M3 locknuts into the holes labelled 2 and 3 on the soil sensor base. The screw heads should be on the same side of the base as the magnets.

Step 5: Add the Jumper Wire

Use wire strippers to remove 5mm of insulation from both ends of the jumper wire.

Attach the jumper wire to the M3 screws using two zipties.