Photoelectric 4-Wire Smoke Detector w/Heat Sensor, Sounder, and End of Line Relay, 8.5 - 33VDC. Smart Dual Fixed/Rate of Rise Heat Sensors. End of line Relay. 85DB Sounder. The 541NCSXTE is a security photoelectric smoke detector from Interlogix which consists of a 4 wire smoke detector, a 8.5 to 33 VDC power source, a sounder, a power relay, a heat sensor, and a UL/cUL listing. The 541NCSXTE security smoke detector comes with a patented CleanMe® feature, an optical chamber replacement, an in-built sounder, plus in-built dust compensation. This quality smoke detector uses a low current draw that is suitable for use with many types of control panels.