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Electro-Mechanical /Solid State / Econolite / Multisonics / Eagle / Traconex / Other

Electro-mechanical Controllers

Here is a picture of a 1959 Econolite traffic controller. This is an "electromechanical" type. This means that the controller uses synchronous motors and an electrical magnetic coil to energize and de-energize a solenoid, which in turn, advances rows of preset cams and contacts (one for each lamp) to mechanically change the signal lamps. It's kind of fascinating to watch. A Lot of human ingenuity was involved to make this controller function so well and fairly reliably in it's time. There are still quite a few of these in operation today, although their numbers are slowly dwindling.

Here is a view of the inside of the Econolite version of the electromechanical cabinet. It shows the inner workings and dial motors on the top shelf, and the flash and dial transfer relays below. The shelf pulls forward and the dust cover is removable for servicing. Also, located on the inside door are the time clocks for intersection flash (late night flash) and for time-of-day changing of the cycle dials. These are mechanical as well and had a feature where, if power were interrupted, the clocks will continue to operate for several hours.

Close up view of the three dial motors. Note that the center dial on Econolite units is dial 1.  The left dial is dial two and the right is dial three.

This view shows the terminal facilities and back panel. The top right relays are the flash transfer relays and break the connection of the red (or yellow) terminals and switch the signals over to flash condition. The blue box on the right is the solid state flasher unit that enables the signals to run in flash. The center two relays are the dial transfer relays and they are of the latching type. Depending on the black knob below, or a time clock, the relays are energized and dial two or three can be selected. When no dials are selected, dial one runs as the default. 




Large Econolite Electromechanical Cabinet- These cabinets were used later in the timeline as signalized intersections became more complex and needed more phases and signal circuits.  This controller controls one turn movement along with two other phases.




Here is an example of one of the older Eagle electro mechanicals. The dial motors on these units are run by a magnetic disc that spins and interlocks with other gears to provide a very accurate cycle for its time. Motors had not been used yet on these units. This controller is from the 40's. These units tended to "stick" in the winter time.

The inside views of this old controller showing the dial gear mechanism and a view of the cam drum with signal contacts.



Eagle EF-20 electromechanical controllers were one of the more popular pre-timed controllers during the last 50 years. They had a very good reputation and track record as one of the lowest maintained signal controllers. Thus, they became very popular throughout the United States. There are still many of these controllers working even today!



The dial motor and cam assembly is located in a separate box that is wired with a harness to the terminal panel in the back. The Eagle version of the dial motor box was kept very clean from dirt with this latching, dust-free box. This was part of the "reliability" in design!



The terminal panel, flash transfer relays and electro-mechanical flasher are located in the back of the cabinet. The dial motor box swings away easily, providing access to all field wire terminals. The light bulb in the lower right serves two purposes. One is for illumination at night, the other is to provide heat during winter months.




View of another EF-20 showing the dial motors and time clock enclosure mounted on the door. Eagle dials are numbered sequentially from left to right..1,2,3.


And here is a Crouse Hinds electromechanical flasher. The cabinet sports the familiar "Art Deco" design, while inside the mechanics are fairly simple...with a motor driven cam and two contacts that open and close alternately, giving one a dual "wig-wag" flash. This rehabilitated unit was mounted on an old street sign.




This is the Crouse-Hinds PCE-1000.  This controller is a bit different, in that the dials are vertically mounted and use a motor driven cam shaft instead of magnetic. Crouse-Hinds also used many relays to change dials and perform different functions. This particular unit is very quiet running and has been fun to refurbish.




And this is my newest acquisition, the Crouse-Hinds KS-2. This is probably one of the oldest controllers in my collection.  It features a magnetic disc that is synchronized to the power frequency. This controller is fun to watch, because there is a brief period of darkness between the signal colors while changing. This is due to the previous indication's contact breaking connection before the next one is engaged.



Electro-Mechanical / Solid State / Econolite / Multisonics / Eagle / Traconex / Other

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