Panel Wiring Terminal Selection: Buchanan 1-282856-3
The TE Connectivity Buchanan 1-282856-3 is a 13-position PCB-mount terminal block from the Buchanan series, designed for fixed-wire power distribution on a board. It uses a screw-actuated rising cage clamp — the clamp lifts to trap the conductor against the bus bar, giving a gas-tight connection that doesn't cold-flow stranded wire over time.
24 A per position is the block's rated current at the stated voltage and temperature. That figure assumes the full conductor cross-section fills the clamp and the ambient stays within the polyamide housing's operating range. For a 13-position block carrying 24 A on every circuit, the total bus-bar current sums to 312 A — the limiting factor is the PCB trace width and the temperature rise inside the enclosure, not the block itself. The 300 V rating covers most industrial control and lighting circuits; for higher-voltage buswork you'd step up to the Buchanan 9.52 mm pitch series.
Wire Termination and Installation
The rising cage clamp accepts 12 to 30 AWG wire. The screw torque spec is 0.79 Nm (7.0 Lb-In) — over-torquing strips the M3 brass screw or cracks the PA66 housing. The clamp and screw are both brass with nickel plating; the contact surface on the bus bar is brass with tin plating. Tin plating is standard for power terminations — it mates well with tinned or bare copper wire and doesn't require gold for corrosion protection in a dry indoor panel. The interlocking side feature lets you gang multiple blocks side-by-side on the same rail without gaps — useful when a 13-position block isn't enough and you need a continuous terminal strip.
It's a current-production Buchanan terminal block, sourced through the standard TE distribution channel. For BOM matching, the pitch, position count, and side-entry orientation are the fixed parameters; colour is the only variable across the -1, -2, and -3 suffixes in this family.
Comparing 1-282856-3 to 1-282856-2
The 1-282856-2 is the same Buchanan 5.00 mm pitch, side-entry, 13-position terminal block in a different housing colour. The -3 is green; the -2 is the standard black/grey Buchanan colour. All electrical ratings (24 A, 300 V), wire range (12-30 AWG), and mechanical specs (torque, screw thread, cage clamp) are identical. The colour difference is cosmetic — pick the one that matches your panel's wire-colour coding or your BOM's existing colour callout. No functional or footprint difference exists between the two.