The VW3A7815 is a high-power braking resistor from the Schneider Electric Altivar range, designed to dissipate regenerative energy from a motor drive during deceleration. Rated at 150 kW average power at 50 °C ambient, with a resistance value of 1.05 Ohm, it handles the thermal load from repetitive braking cycles in Altivar drive systems. The IP23 enclosure allows indoor installation in a clean, dry environment — not suited for washdown or outdoor placement without additional shelter.
The 1.05 Ohm value sets the peak braking torque capability — lower resistance draws more current and provides stronger braking, but the drive's braking chopper must be rated for that current. The 150 kW average power at 50 °C is the continuous dissipation rating; for intermittent braking duty (typical in conveyors, centrifuges, or hoists), the resistor can handle higher peak power for short periods, but the average over the duty cycle must stay under this figure. Thermal protection is built in via a thermal overload relay, which should be wired to the drive's safety input to prevent resistor meltdown if the duty cycle is exceeded.
Physical integration — panel space and connections
At 1140 mm wide × 1150 mm tall × 820 mm deep, this is a floor-mount or large-panel unit, not a DIN-rail component. Plan for a dedicated mounting footprint and adequate clearance for airflow — IP23 means natural convection cooling is expected, so stacking or enclosing it without ventilation derates the power. The M10 bar wire connection requires appropriate lugs and torque tooling; verify the drive's braking terminal size matches before terminating.