What the key ratings mean for your selection
The 398900303: The 13.5 A current rating is per contact at the circuit level — for a 3-position block each pole independently carries that load, so the rating is not divided across positions. The 300 V ceiling is the insulation voltage; verify the working voltage of the circuit is comfortably below that limit before committing, particularly in any UL/CSA field-wiring application where creepage and clearance at the PCB entry are driven by that number. Contact finish is tin-plated copper alloy over a nickel underplate. Tin plating suits the wire gauge range of 16-30 AWG and the 13.5 A rating — there is no gold on the current-carrying contact face, which is appropriate for power-distribution duty rather than high-cycle signal. The nickel underplate on the clamp and screw hardware resists corrosion at the mechanical interface, where the recurring torque cycles would expose bare copper if left unplated. Housing material is polyamide (nylon), rated for operation from -40 °C to 105 °C. That range covers most industrial enclosure environments; the upper limit is set by the housing, not the contact, so thermal cycling in a poorly ventilated panel should be evaluated against 105 °C rather than assumed safe at any lower ambient.
Where this class of connector is used
Rising-cage terminal blocks in the 5.00 mm pitch class are the workhorse of industrial automation power distribution at the PCB node — they bridge the field wiring from 16-30 AWG harness leads to the board-level power rails at a known, repeatable torque. The interlocking side feature allows panel builders to gang multiple 3-position blocks into a multi-pole supply or ground bus without custom bus bars, making the Eurostyle 39890 a scalable building-block for control cabinet construction.