Final answer:
Occupancy sensors have two modes of operation: manual on and automatic on. The question asks about the power consumption requirement for occupancy sensors, with an exception for warehouses.
Step-by-step explanation:
An occupancy sensor is a device that detects when a person is present in a space and controls the lighting or HVAC systems accordingly. In most cases, occupancy sensors have two modes of operation: manual on and automatic on. In the manual on mode, the sensor requires a manual switch to turn on the lights or other devices. In the automatic on mode, the sensor detects motion and automatically turns on the lights, without the need for a manual switch.
According to the question, occupancy sensors must require either a manual on switch or an automatic on switch to consume a certain percentage of power or less. The exact percentage is not mentioned in the question. However, it is specified that warehouses have an exception to this requirement. This means occupancy sensors in warehouses may not need a manual or automatic switch, or there may be different power consumption regulations for warehouses.