Project Overview
System Philosophy
The entire FarmBot bed is mobile. To support this, all power and network connections terminate at a single FarmBot electronics enclosure mounted on the wooden bed side wall. One AC power cable and one ethernet cable plug into this box — everything else is internal distribution. Moving the bed means unplugging two cables.
Power flow
AC Mains
→
24V 150W PS
→
24V rail A
→
Farmduino + motors
AC Mains
→
24V 100W LED driver
→
24V rail B
→
Grow lights (relay)
24V 100W LED driver
→
Buck → 12V
→
Zone sensors
24V 100W LED driver
→
Buck → 5V
→
Pi 3B + Nano
Power rails
FarmBot main supply 24V · 150W
Powers all FarmBot motion and control hardware. Dedicated supply keeps motor noise off the sensor and compute rails.
- Farmduino controller 24V
- NEMA 17 stepper motors (x4) 24V
- FarmBot Raspberry Pi 4B 24V → regulated
- Water pump relay (peripheral 4) 24V
- Lighting relay (peripheral 5) 24V
LED driver supply 24V · 100W
Powers grow lights directly and feeds buck converters for 12V and 5V distribution to sensors and compute.
- Barrina grow lights (6x) 24V
- Buck converter → zone sensors 12V out
- Buck converter → Pi 3B 5V out
- Buck converter → Arduino Nano 5V out
- 5-port network switch 5V or PoE
Enclosure contents
Component
Qty
Notes
FarmBot Genesis electronics enclosurev1.2 — repurposed from FarmBot garage sale
1
Main distribution box — mounted on wooden bed side wall
24V 150W power supplyFarmBot main PS
1
FarmBot motion and control power
24V 100W LED driverGrow light supply
1
Grow lights + buck converter input
Buck converter 24V → 12V
1
Powers RS485 zone sensors
Buck converter 24V → 5V
1
Powers Pi 3B and Arduino Nano
5-port gigabit switchTP-Link Easy Smart — PoE powered
1
Network hub for Pi 3B, Pi 4B, and future devices
Terminal blocks
As needed
Power distribution — one per voltage rail
Cable glandsPG7 (small) and PG9 (medium)
8–10
One per cable entry/exit point — already on hand
Cable gland layout
Cable
Size
Wall
Notes
AC mains in
PG9
Bottom
Single AC input for whole system
Ethernet in
PG7
Bottom
Single network input for whole system
FarmBot 24V to Farmduino
PG9
Side
Main FarmBot power cable
Grow light cable
PG9
Side
24V to grow light array
12V to sensor enclosure
PG7
Side
Powers RS485 zone sensors
5V + ethernet to Pi 3B
PG9
Side
Power and network to camera Pi
Ethernet to Pi 4B
PG7
Side
Network to FarmBot Pi
USB to Nano enclosure
PG7
Side
Serial connection to sensor hub
Wiring notes
- Set buck converter output voltage BEFORE connecting any load — use a multimeter to confirm 12V and 5V before plugging in devices.
- The 5-port switch is PoE powered — check input voltage compatibility with your 5V buck output before connecting.
- Keep AC mains wiring physically separated from low voltage DC wiring inside the enclosure.
- Use terminal blocks for all power distribution — no wire-to-wire splices inside the enclosure.
- Label every cable at both ends before routing — essential for a mobile system that gets unplugged regularly.
- Orient all cable glands downward or sideways — never upward — to prevent water ingress.
- Use ferrite cores on USB and ethernet cables near the enclosure to reduce motor noise interference.
- The system is mobile — use strain relief at every cable gland to protect connections during moves.
Build phases
1
Drill and fit cable glands
Mark gland positions on enclosure walls, drill with step bit, fit and tighten all glands. Confirm all cables pass through cleanly with strain relief.
2
Mount internal components
Mount both power supplies, buck converters, and network switch inside the enclosure. Use M3 screws or adhesive standoffs. Plan wire routing before final mounting.
3
Install terminal blocks and wire power rails
Mount terminal blocks for 24V rail A, 24V rail B, 12V, and 5V. Wire power supplies to terminal blocks. Verify all voltages with multimeter before proceeding.
4
Set and verify buck converter outputs
With no load connected, power each buck converter and adjust output to exact target voltage — 12.0V and 5.0V. Confirm with multimeter. Only then connect loads.
5
Route and connect output cables
Run cables through glands to each device — FarmBot, grow lights, Pi 3B, sensor enclosure. Label both ends of every cable. Connect to terminal blocks and confirm continuity.
6
Network wiring and switch configuration
Connect ethernet from wall to switch input. Run ethernet cables to Pi 3B and Pi 4B. Configure switch VLANs and QoS if needed. Verify network connectivity on all devices.
7
Full system power-on test
Power up entire system from single AC input. Verify all devices boot correctly, network is accessible, FarmBot connects to web app, camera stream is live, and sensors are reading.