Photoelectric smoke detector equipped with smoke detecting function test means

摘要

This invention relates to a photoelectric smoke detector which is capable of readily and precisely checking by itself whether light intensity reaching the smoke detector is within the normal level at which no false alarm, alarm failure nor delayed alarm is caused on the basis of the signal sent from a control panel through the lines connecting between the smoke detector and the control panel, and of reporting the result to the control panel through the same lines.