Trolley Car Electric Switches

Can any trolley fan out there explain how the real streetcar electric switches (turnouts) worked electrically? As I understand it, there was an
extra contact next to the trolley wire that contacted the side of the shoe at the end of the trolley pole before the track turnout. If the car coasted past this contact, the turnout was thrown one way, and if the car was drawing power, the turnout was thrown the other way. I'm guessing there may have been some resistance in the feed to the trolley wire by the contact so the system would see a different voltage drop depending on whether the car was coasting or not. Does anyone know for sure? (On a G gauge layout, I want the trolleys to take one route to stay on a little loop, while I want the steam trains to go the other way on the main line. I can use the LGB magnetic reed switches in the track to route the steam trains, but need something different to sense the approach of the streetcars.) Geezer
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At the Toronto Transit Commission (TTC), 'Neccesity Action' electric switches are controlled by a contact on the overhead and a switch button on the dash of the streetcar. If the button is pushed in as the trolley pole hits the contact on the overhead, the track switch will change from the straight position to the curved position, or will remain in the curved position. If no action is taken by the operator, the track switch will remain in the straight position or will return from the curved postion to the straight position. A similar 'Self Restoring' electric switch is also used in some locations. The operator must physically change the track switch from the straight to the curved postion, but the next car along will automatically restore the track switch to the straight position.
Prior to about 1945, the TTC, and most other streetcar properties used electric switches which used 'power on' and 'power off' to change the direction of the track switch. This led to several open-switch accidents with other streetcars and was the major reason to changing to the current system.

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On the Boston MBTA the motorman reached out the cab window and flipped a control mounted on the tunnel wall. At least on Arborway cars going thru Copley.
David Starr
Roy & Lynn Williams wrote:

are controlled by a contact on the overhead and a switch button on the dash of the streetcar. If the button is pushed in as the trolley pole hits the contact on the overhead, the track switch will change from the straight position to the curved position, or will remain in the curved position. If no action is taken by the operator, the track switch will remain in the straight position or will return from the curved postion to the straight position. A similar 'Self Restoring' electric switch is also used in some locations. The operator must physically change the track switch from the straight to the curved postion, but the next car along will automatically restore the track switch to the straight position.

electric switches which used 'power on' and 'power off' to change the direction of the track switch. This led to several open-switch accidents with other streetcars and was the major reason to changing to the current system.

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At the Toronto Transit Commission (TTC), 'Neccesity Action' electric switches are controlled by a contact on the overhead and a switch button on the dash of the streetcar. If the button is pushed in as the trolley pole hits the contact on the overhead, the track switch will change from the straight position to the curved position, or will remain in the curved position. If no action is taken by the operator, the track switch will remain in the straight position or will return from the curved postion to the straight position. A similar 'Self Restoring' electric switch is also used in some locations. The operator must physically change the track switch from the straight to the curved postion, but the next car along will automatically restore the track switch to the straight position.
Prior to about 1945, the TTC, and most other streetcar properties used electric switches which used 'power on' and 'power off' to change the direction of the track switch. This led to several open-switch accidents with other streetcars and was the major reason to changing to the current system.
Thanks for the info. Do you know what pushing the button does electrically, such as does it impose an AC control signal onto the 600VDC ? Geezer
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