THE FIRE SERVICE INSTRUCTOR
Concluding Installment of a Treatisa to Aid Those Responsible for Training Men in the Fire Service to Develop a Systematic Type of Teaching
Battalion Chief, Director
Chapter IV (Concluded)—Helps in Teaching
General Description of Aero System (Continued)
Manual Fire Alarm Stations
THE Aero manual station is of the “one operation break glass” type and is so designed that it can be assembled onto any detector unit. The addition of manual stations to an Aero system does not change the wiring or operating scheme and is accomplished by merely adding extra contacts to the diaphragm frames and providing manual covers.
Control Panel with Transmitter and Relay
The control panel consists of two clock-driven transmitters with a retard and associated relay. One transmitter is used to give trouble signals and the other operates for fire alarm signals.
In case of failure or weakening of the local battery or other features which might prevent the transmitting of a signal the trouble clock is released.
Sudden flashes of heat causing a momentary closure of the detector contacts are controlled by the retard which is not de-energized along enough to cause the transmission of a signal.
Closure of the diaphragm contacts causes the operation of the alarm transmitter, sending a distinctive fire signal and also operating the local gongs.
Annunciators and Bells
The annunciator operated from the unit detector sets is used to show the exact location of the fire. This is usually placed on the outside of the building, but an interior type may be provided where necessary. It consists of a red enameled weather-proof cast iron case, provided with targets or drops visible when in their actuated position.
The local alarm bells are of the single or double vibrating type, located so as to give a general alarm throughout the building on the outbreak of fire.
Source of Energy
Current for the operation of the Aero system is supplied from a storage battery with automatic charger where A.C. current is available; otherwise, a suitable storage battery is used. Aero alarms also register on Sprinkler supervisory and Valve alarm Circuits if connected to same.