Time lock switches are used on prototype railroads to prevent a crew from opening a switch in front of an oncoming train.  The Time Lock Switch Controller provides an easy way to add prototypical time-locked switches to your model railroad.  For those with Centralized Traffic Control (CTC) or other dispatcher controlled power switches, the Time Lock Switch Controller can be used to simulate dual-control power switches, allowing the crew to override a power switch locally.

Features

• Simulates time lock switches and dual-control power switches
• Adjustable time delay, from 5 - 240 seconds
• Built-in 2kΩ shunt resistor and relay for triggering current-based block occupancy detectors
• Directly drives MRServo switch machines or popular stall-motor type machines
• Requires only a single input for turnout direction
• Includes key switch with 2 keys and a white LED
  

The Prototype

Prototype railroads use time locks on uncontrolled switches in signaled territory – often into industrial sidings - to prevent a crew from opening a switch in front of an oncoming train that is expecting clear track based on the last signal they saw.  The time delay between a crew requesting to operate the switch and actually being able to move the points is enough that any train already past the nearest block signals would have also passed the switch.

Even the best of machinery fails, and when that machinery is a switch at a busy control point, there is not always time to wait for the maintainer to get there.  That's why most prototype power switch machines on North American railways are “dual-control,” meaning they can be operated remotely under power or operated locally with a hand-throw lever.

While common on the prototype, these unique elements of switching industries are seldom modeled.  Now, with the CKT-TIMELOCK, it is easy to add additional realism for your switch crews on your layout.

Specifications

2.1"(L) x 0.95"(W)

Documents

The complete gEDA design files are available on GitHub.

User Manual

Schematic