The 500 Series self-diagnostic, two & four wire smoke detectors are conventional direct-wire smoke detectors with analog features such as remote maintenance/trouble reporting (CleanMeŽ), drift compensation, and multi-criteria detection.
The 500 Series continually monitor their own sensitivity and operational status, and provide a visual and remote trouble condition if they drift out of the sensitivity range or fail internal diagnostics. This meets NFPA 72 field sensitivity testing requirements without the need for external meters.
The 521 has a unique feature enabling it to send a signal (CleanMe) to the ESL 505 module (sold separately) when it has drifted outside of its UL Listed sensitivity range or has failed its internal diagnostics test.
The 505 is an interface module that will signal a 24V panel via relays when the 2-wire smokes are dirty. Several 12V and 24V control panels have the CleanMe software built in, eliminating the need for the 505 module. When CleanMe is not desired, simply leave the switch on the two wire devices off and it will work as a normal two wire detector.
CleanMe allows the installer time to schedule a service call and avoid a false alarm. Time between cleaning detectors is dramatically increased because of the 500 series built-in drift compensation. This feature, usually only available in analog systems, allows the detector to automatically adjust its sensitivity over time as it becomes dirty, increasing the life of the detector. And when the 500 series smoke detectors have told you that cleaning is necessary, it's literally a snap with a patented field replaceable optical chamber (part number 211).
Additional Features Compatible with wide array of panels Built-in sounder eliminates need for separate horns or sirens