WattStopper s Neutral Sense Technology Complies with 2011 NEC requirements Zero crossing circuitry reduces stress on the relay and results in increased sensor life Adjustable time delay and sensitivity Custom two tier Fresnel lens enhances detection at the desktop level Sensor coverage tested to NEMA Guide Publication WD 7 2000 Light level sensor holds lights off when ambient lighting is above the preset level Patented voltage drop protection For safety, there is no leakage to load in the off mo