The Intelligent Photoelectric/heat, spot-type smoke detectors, P/N 63-1053 & 63-1059, have sensing chambers that utilize the light scattering principle to detect smoke. In addition, the detector is equipped with dual thermistors for heat sensing. The sensing chamber employs features that minimize the effect of settled dust on performance. The detector is designed with tri-color LEDs to indicate detector status. A remote LED annunciator, P/N 02-3868, is available as an accessory. It can be configured to follow the detector LED operation or be independently controlled. The heat element of the detector provides an alarm, while the photo element can be programmed as alarm or supervisory. The isolator version, P/N 63-1059, provides complete short circuit isolation for NFPA 72, Class X wiring if used with an isolator base.