The TA1AD3L8004TPE is a Schneider Electric TransferPacT automatic transfer switch rated for 800 A at 400 V AC, 50/60 Hz, in a 3-pole configuration. It's a PC-class switch — meaning the contacts are rated for making and breaking fault currents, not just isolation — built to change the source of supply in a critical power path. The AC-33B utilization category tells you it's designed for mixed motor, resistive, and lightly inductive loads, so it's suited for generator-to-mains or dual-feeder switching in commercial and industrial panels. The switch carries an uninterrupted duty rating, meaning it's built to stay closed continuously without derating — no need to oversize for continuous current. The LCD screen shows operating mode and status, and the control is automatic with a manual override option.
The short-time withstand current (Icw) is 50 kA for 0.5 s and 70 kA for 0.1 s, which governs coordination with upstream protective devices: the switch must be able to hold through the clearing time of the breaker feeding it. The making capacity (Icm) is 105 kA as a switch-disconnector alone, and 154 kA with an upstream protection circuit breaker — that's the peak current it can close into without welding. The switch is suitable for isolation — it has a visible contact position indicator and a padlockable OFF position, so you can lock it out for maintenance. The mechanical interlocking prevents both sources from closing simultaneously, which is standard for changeover switches.
Mounts fixed to a plate — no DIN rail. The footprint is 540 mm wide, 391 mm high, 383.5 mm deep. Connection pitch is 115 mm, and both upside and downside connections are screwed, so you'll need a torque wrench and a decent-sized enclosure.