Time Lock Switch Controller
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.
- 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
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.
2.1"(L) x 0.95"(W)
The complete gEDA design files are available on GitHub.
- 12 or more $30.00
- 2 in stock
News & Application Notes
Modelling Time Locks on Switches
Time Locks – An Introduction
In the real world, manual switches within signalled territory are protected by devices called “time locks”. The purpose of these is to prevent a switch from being opened in the face of an approaching train. When the conductor wants to open the switch, he unlocks it and starts the timer running (how this is done depends on the model of time lock). The time delay gives any train too close to stop – or sometimes too close to even see a restricting signal – time to safely pass over the switch before the points are changed. It also triggers the signal system to display restricting aspects around the block, so trains that are further out are alerted to the presence of an open switch.
Once a programmed amount of time has passed, the timer indicates to the user that it has expired (often by a white or green light) and then releases a locking mechanism that allows the points to be moved manually. (This is commonly done with a locking pin through the throwbar that is retracted, but there are other mechanisms.)
Time locks aren’t just a good idea – they’re required by law here in the US. Under 49 CFR 236.207, either approach or time locking is required of manual switches in signalled territory.
Several people asked about the control panels we had on our demos at the St. Louis RPM meet. They are easy to make, so I figured I’d share the process.Read More...
See you in St. Louis
We will be at the St. Louis RPM Meet later in the week with several new products to demonstrate. If you are there, please stop by and introduce yourself. During that time, online orders may be delayed, but don’t worry – we will get to them as soon as we get back home. As a preview, here is a video of the Interlocking In A Box prototype.Read More...