The Schneider Electric TA10D3L0404TPE is a TransferPacT automatic transfer switch (ATS) rated for 40 A continuous at 400 V AC, 50/60 Hz, in a 3-pole configuration. It is designed to change the source of supply — the core job of an ATS — and is classified as a PC-class transfer switch per IEC 60947-6-1, meaning it can make, carry, and break currents but does not provide overcurrent protection. That isolation is handled upstream.
The utilization category AC-33B covers mixed loads including motors, resistive, and lightly inductive, which is the typical mix in a commercial or light industrial backup-power panel. Short-circuit performance is specified two ways: Icw of 5 kA for 0.1 s (the switch can withstand that fault current until the upstream breaker clears it), and Icm of 15 kA making capacity at 400 V when the switch-disconnector alone handles the fault. With an upstream protection circuit breaker, the making capacity jumps to 75 kA at 400 V — that is the practical installation condition for most panels, so the 75 kA figure governs the real-world coordination study. Rated insulation voltage (Ui) is 800 V on the switch side, 500 V on the controller — the controller electronics see lower stress, but the power path is rated for 800 V isolation, which covers 480 V and 600 V class systems with margin. Impulse withstand (Uimp) is 6 kV on both sides, standard for distribution-level equipment in pollution degree 3 environments (industrial, not clean-room).
The switch mounts on a plate or DIN rail — the 310 mm width and 147 mm height mean it will span multiple DIN-rail modules; plan for a 310 mm wide cutout or a plate large enough to clear the 94 mm depth behind the panel face. Connection pitch is 18 mm, and both upside and downside connections are screwed terminals, so no special crimp tooling required. The front face is IP40 in auto mode (tools and fingers stay out), and IP20 inside the enclosure in manual mode — fine for a locked panel.