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Single Components

Disclaimer

  • Recommendations are not universal; they are starting points to begin your own efforts.
  • No information here replaces the advice of a professional.
  • Document, label, and test your wiring harnesses!
  • Test your crimps!
Reading Entries
  • Name: an abbreviation for what the pin does. This is for identification only.
  • Pin #: order of the pin in the connector.

  • Color: optional color-coding for the wire insulation.

    • Colors are solely to help visual identification.
    • Colors do not always match the wire colors that usually tail a component; this is meant to maintain internal consistency.

  • Typical AWG: This is the gauge that is most often used for a given component.

  • Common Termination: The type of cable termination found most often for a component

See the tips page for a more details explanation.

General Components

Hotend

Name Pin # Color
VIN 1 R 🔴
GND 2 K black
  • Typical AWG: 20
  • Common Termination: screw post terminals or Molex Micro Fit 3.
  • Notes:
    • Polarity does not matter.
    • Many JST connectors are limited to 3 amperes. This may be insufficient after derating for parallel conductors (and ambient temperature for enclosed printers).

Heated Bed

Name Pin # Color
VIN 1 R 🔴
GND 2 K black
  • Typical AWG: none, specific to bed
  • Common Termination:
    • Screw post terminals (bare/ferrules)
    • Screw block terminals (ring/fork)
    • XT60 connectors
  • Notes:
    • Some beds also use a number of parallel circuits with lower-amperage connectors.
    • AC beds need a protective earth connection.

Stepper Motors

Name Pin # Color
1A 1 R 🔴
1B 2 B 🔵
2A 3 G 🟢
2B 4 K black
  • Typical AWG: 24
  • Common Termination:
    • Board: JST XH, 4 position
    • Component: JST PH, 6 position or bare wire
  • Notes:
    • There is not a standard wire color or pin order for stepper motors.

Protective Earth

Name Pin # Color
PE 1 G 🟢 / K black
  • Typical AWG: none, specific to configuration
  • Recommended Connector: Ring connector

Fans

Fan (2 Pin)

Name Pin # Color
VIN 1 R 🔴
GND 2 K black
  • Typical AWG: 24/28
  • Common Termination: JST XH, 2 position
  • Notes:
    • 24 awg is easier to crimp; 28 is sufficient.

Fan (3 Pin)

Name Pin # Color
VIN 1 R 🔴
GND 2 K black
TAC 3 Y 🟡
  • Typical AWG: 24/28
  • Common Termination: Molex KK 254, 3 position (Molex PN 22013037)
  • Notes:
    • 24 awg is easier to crimp; 28 is sufficient.
    • This reverses the typical GND/VIN pin order of most 4-pin fans.

Fan (4 Pin)

Name Pin # Color
VIN 1 R 🔴
GND 2 K black
TAC 3 Y 🟡
PWM 4 G 🟢
  • Typical AWG: 24/28
  • Common Termination: Molex KK 254, 4 position (Molex PN 470541000)
  • Notes:
    • 24 awg is easier to crimp; 28 is sufficient.
    • The pin order chart reverses the typical GND/VIN pin order of most 4-pin fans.

Analog Sensors

Most sensors on a printer send analog signals, from thermistors to ABL sensors. These typically use 2- and 3-position connectors.

Unpowered Sensors (2-wire)

Examples of unpowered sensors are mechanical limit switches and thermistors.

Name Pin # Color
SIG 1 Y 🟡
GND 2 W white / K black
  • Typical AWG: 24/28
  • Common Termination: JST XH is frequently used
  • Notes: none

Powered Sensors (3-wire)

Examples of powered sensors are optical limit switches and magnetic ABL sensors. Filament runout sensors may also be 3-wire.

Name Pin # Color
VIN 1 R 🔴 / B 🔵
SIG 2 Y 🟡
GND 3 K black / W white
  • Typical AWG: 24/28
  • Common Termination: None
  • Notes: none

Digital Components & Buses

BLTouch

BLTouches can be configured to work with 3.3V or 5V.

Name Pin # Color
VIN 1 R 🔴 / B 🔵
GND 2 K black
PWM 3 G 🟢
SIG 4 Y 🟡
GND 4 W white / K black

I2C

I2C is a 3.3V digital signalling bus. Short cables and eliminating EMI are important to working with I2C. I2C is often used with embedded devices such as atmospheric monitoring sensors.

Name Pin # Color
VIN 1 R 🔴 / B 🔵
GND 2 K black
SDA 3 Y 🟡
SCL 4 G 🟢
  • Typical AWG: None
  • Common Termination: Adafruit and SparkFun use JST SH connectors for I2C.

SPI

SPI is, like I2C, a 3.3V digital bus. It is slightly more forgiving of distance than I2C, but still suffers from noise and voltage drop. It is commonly used for ADXL-series accelerometers.

Name Pin # Color
VIN 1 R 🔴
GND 2 K black
SCLK 3 G 🟢
CS 4 B 🔵
MOSI 5 Y 🟡
MISO 6 W white
  • Typical AWG: None
  • Common Termination: None