MTA-156 4-Position IDC Receptacle for Discrete or Ribbon Cable
The 3-640428-4: The 0.156" (3.96mm) pitch is wider than the common 0.100" IDC standard, which makes the wire-to-wire spacing more forgiving during harness assembly and reduces the risk of adjacent wire shorting in high-vibration environments. The housing is red and features a closed end, meaning one side of the connector is walled off to provide a positive stop for the cable and prevent over-insertion.
IDC Termination and Field Installation
For discrete wires, a simple hand tool or arbor press works; for ribbon cable, the connector can be mass-terminated in one stroke. The closed end acts as a cable stop, so the wire bundle sits flush against the back wall of the housing, which helps with strain relief in the harness.
The 1-row, 4-position layout is keyed by the closed end — the header must be oriented so the open side aligns with the receptacle's open side. No secondary lock or TPA is used; the IDC termination and the locking ramp are the only retention features. For a 4-circuit harness, this is a straightforward mate — no polarisation keys or colour coding beyond the red housing.