Panasonic HD-T1 series has a maximum current consumption of only 70 mA, for both the sensor head and the controller. The current consumption is almost as low as that of photoelectric sensors. Although the HD-T1 series uses a red LED for its light source, it has the same high level of performance as laser sensors, thus enabling high precision detection. As both the receiver and the emitter are integrated into a single unit, there is no need to perform any troublesome alignment of the beam axis. In addition, as the HD-T1 series can perform its detection function over a broad area - with both a sensing range and a sensing width of 30 mm 1.181 in, this unit can be utilized for sensing wafers of many different sizes. As a safe red LED is used as the light source, there is no need for time-consuming safety measures. The protective covers usually required when using laser beams are not needed, and FDA approval is not required in order to use this sensor in the US. This unit is equipped with a one-touch connector to connect the sensor head to the controller. The amount of wiring is therefore minimized, resulting in easy maintenance.