Check Wire Polarities

The endstop wire polarities of BigTreeTech and Mellow are different. Please swap the wires if necessary.

Check the terminals

Some of the terminals are connected by the clamping force of the terminal itself. Please double check that they are firmly connected. 

If you plan to solder the terminals, cover the joint with enough solder to lower the electrical resistance and possible heat generated. Common solder has a melting temperature 180~240°C which is higher than the wire sheath. Avoid use low temperature (100~130°C) solder.

Group A: Power Supply Unit

• Terminal block

• Bus bar, Red

• Bus bar, Black

• Power switch

• Power supply unit

• AWG16, 10cm, Red (L)

• AWG16, 10cm, Black (N)

• AWG16, 10cm, Yellow-Green (GND) 

Actions

Install the power switch at the left side of the frame (beta version), or the lower slot (formal version).

Before connecting other electronic components, test the power supply unit independently first.

1. Make sure you have chosen the AC voltage in the PSU suitable for your country.

2. Connect the red, black and blue wires of the power socket to L, N, and ⏚ (ground) terminals on the PSU.

3. Turn the switch ON and see if the indicator is lit. The fan will turn only when temperature condition is met.

4. If you have a multi-meter, verify voltages of each terminal.

Connect the grounding wire to the frame. If your frame is black, grind the black layer off so the wire contacts with bare aluminum material.

Under normal condition there is NO electricity at the grounding wire and frame. The grounding wire provides a bypass path in short circuit condition and prevent you from electric shock.

If an abnormal short circuit condition happens, the circuit breaker in your house breaks and stops providing electricity immediately.

Exams

Double confirm the connectors both at the switch side and PSU side are FIRMLY CONNECTED. Heat will accumulate at a loose contact point, melt surrounding plastics and cause short-circuit!

Group B: BTT Octopus Pro

• Octopus Pro board

• AWG16, 35cm, Red (Power+)

• AWG16, 35cm, Black (Power-)

• AWG16, 5cm, Red (x2) (Daisy chain +)

• AWG16, 5cm, Black (x2) (Daisy chain -)

Exam

Be ware of the L & R driver positions to meet the CoreXY belt route in Tank v2.

Group C: Bed heater

• 600w bed heater

• SSR

• Fuse box

• AWG20, 35cm, Red (Ctrl +)

• AWG20, 35cm, Black (Ctrl -)

• AWG16, 20cm, Red (Fuse-TerminalBlock)

• AWG16, 5cm, Red (Fuse-SSR)

Group D & G: PTC chamber heater

• PTC heater

• Power switch

• SSR

• Fuse box

Group D

• AWG20, 35cm, Red (Ctrl +)

• AWG20, 35cm, Black (Ctrl -)

• AWG16, 10cm, Red (Fuse-TerminalBlock)

• AWG16, 5cm, Red (Fuse-SSR)

Group G

• AWG16, 40cm, Black (PTCHeater-PowerSwitchN)

• AWG16, 180cm, Red (Button-PowerSwitchL)

• AWG16, 150cm, Red (Button-FusePTCHeater)

(For Beta kits only: The 40cm and 180cm wire above are in wrong colors. 🙏)

Actions

For safety reason, the PTC heater is arranged to another power switch and doesn't share the power capacity of the rest of circuit.

Install the other power switch at the right side of the frame (beta version) or the upper slot (formal version).

Group F: Emergency stop button

• Emergency button

• AWG16, 120cm, Red (Button-PowerSwitch)

• AWG16, 140cm, Red (Button-TerminalBlock)

The emergency stop button is held tightly to the frame by the 2 screws pushing against the surface, so no screw holes of specific dimension are on the frame piece.

Group H: Tool head, CAN bus

• Hotend heater extender cable

• EBB36 customized cable

Actions

The VIN of EBB36 is connected to 24V, not the mains power.

Connect the hotend heater wires to the Octopus Pro board due to power capacity and the limited space near the heater port of EBB36.

Connect the other electric components at the toolhead to the EBB36 board.

(For beta kits only: 

1. Please swap the 2 CANBUS wires for CANBUS function to work. 

2. Please customize and crimp a cable for the X & Z endstops using the pins and XH2.54 5p male connector in the EBB36 box. The X & Z endstop shares the 5-pin socket on the EBB36 board.)

The correct wire connections are shown in the pictures. 

Exam

Make sure the pins in the connectors are wired to the correct slots in the other connector.

The 120R jumper is put on the EBB36 board.

The VIN of EBB36 is connected to 24V, not the mains power.

Inductive ABL sensor

If you didn't choose the DAB extruder carriage as Z endstop, an inductive sensor is included in the kit and acts as the Z endstop.

Connect the wires as shown in the picture. Sometimes the color sequence change in different batches, just match the wires based on color and tape them from falling apart.

Plug the ABL sensor to the Z endstop endstop. The polarity of endstop sockets in BigTreeTech board and Mellow board are different. Please follow the according pictures.

The LED on the sensor should light up when no metal object is nearby, and dims while being triggered.

Debug with a multimeter

Sometimes you want to check the voltage of a certain pin, be VERY careful if you are probing. A careless short circuit might damage unknown parts of the main board and result in unexpected behavior.