How to Install Electric Bells, Annunciators, and Alarms. / Including Batteries, Wires and Wiring, Circuits, Pushes, Bells, Burglar Alarms, High and Low Water Alarms, Fire Alarms, Thermostats, Annunciators, and the Location and Remedying of Troubles

by Norman H. Schneider

Three Wire Return Call System.

A three wire return call annunciator system is shown in [Fig. 60].

There are two battery wires installed, from which taps are taken off and led to each room or push button.

Three way or return call push buttons are used as shown at points marked B.

In the diagram, the bells are marked A, the drops in the annunciator D, the annunciator bell C and the return call buttons in the annunciator E. The batteries are as shown at F. The heavy black outline encloses the annunciator mechanism and connections which are drawn diagrammatically for the sake of clearness.

Three stations only are shown on the sketch, but the annunciators which are manufactured by Edwards and Co., Inc., of New York, are made in all standard sizes.