The PAD300-PHD is a listed Analog Addressable smoke detector and a rate of rise and/or fixed temperature heat detector compatible with fire alarm control panels that utilize the Potter Addressable Device (PAD) protocol. The PAD300-PHD is a low profile smoke/heat sensor with a wide sensitivity range. The heat sensing portion utilizes a proven thermistor for accurate and reliable heat detection. The detector and base are made of a durable plastic in an off-white color to blend in with the ceiling. The PAD300-PHD is UL listed and has a sensitivity range of 1.1 to 3.5% per foot with a fix temperature alarm threshold of 135°F and can be used for rate of rise applications. See detector spacing limitations below. The PAD300-PHD features drift compensation and has built in dirty detector warning. The PAD300-PHD and the control panel communicate over a proven and robust digital communication path and the system analyzes the information at the particular device. The total polling speed is less than five (5) seconds, well under the UL requirements. The detector is compatible with any of the PAD300 series detector bases and simply twists on. The PAD300-PHD is addressed using DIP switches in the rear of the detector and can be easily programmed in the field without special tools.