The VW3A66712 is a Speed Dynamic Brake resistor from Schneider Electric's Altivar drive family, sized for a 10 HP motor load. It's the component that absorbs regenerative energy from a decelerating motor — without it, the DC bus on the drive would trip on overvoltage every time you try to stop a high-inertia load quickly.
The 10 HP rating matches the resistor to a drive power stage rated for that motor size — oversizing the resistor doesn't hurt, but undersizing it will cook the resistor element on the first hard stop. The NEMA 1 enclosure means it's ventilated for indoor use where dripping water or falling dirt is a concern, but it's not sealed against washdown or outdoor weather. Surface mounting is the standard approach: bolt it to a non-flammable vertical surface with clearance around the vents for convective cooling. The thermal protection (a built-in thermal switch or PTC) is there to open the drive's braking control circuit if the resistor overheats — don't bypass it, or you lose the fault protection that keeps the resistor from becoming a fire source.
This resistor connects between the DC bus terminals (PA/+ and PB) on the Altivar drive — typically the same frame size as the 10 HP drive it's paired with. The thermal protection leads run back to the drive's braking control input. Keep the cable run under 10 meters to minimize inductance that can cause voltage spikes across the IGBT braking transistor. Mount the resistor so its hot-air exhaust doesn't recirculate into the drive's cooling fan intake.