FRA Issues Safety Advisory 2025-01 for Proper Configuration of Grand Master 4000 and 4000A Switch Machines

FRA

WASHINGTON, D.C. - The Safety Advisory was issued to increase awareness of the potential for "unintended movement" of the machines. If improperly configured, the machines could allow for the presence of power that would lead to unintended switch movement.

According to the advisory from the FRA, produced below, the Grand Master 4000 and 4000A is “an electric switch machine designed to be used at controlled points, interlocking and derails.” Recently, a derailment occurred that was caused by intended movement of a switch. This unintended movement was the result of improper configuration of the machine amplifier. The FRA states the amplifier “was configured in the 3 wire position and not the intended 4 wire position.” Additionally, the Grand Master 4000A switch machine amplifier has the same design and is at risk of causing unintended movement.

The machines have four different configurations available to be selected and a 3W/4W controller key switch or plug that must then be in the correct position based on the previously chosen wiring configuration. Testing showed that if either machine is in the 4-wire configuration and the 3W/4W controller key switch or plug is in the 3W position, it can allow for power to be in the switch machine controller “when locking is required to be in effect.” This can lead to unintended movement of the switch.

The recommended actions for railroads is as follows:

1. Ensure signal circuit plans for each Grand Master 4000 or 4000A machine show which correct wiring configuration is used and the proper position of the 3W/4W controller key switch or plug. This should remain consistent.
2. Ensure wiring configuration of either switch machine and the 3W/4W controller key switch or plug match the signal circuit plans.
3. Include a test to be sure that power is removed from the switch machine controller when locking is required. This can be performed “by the placement of a 0.06-ohm shunt in the OS and visual confirmation that all lights on top of the controller are dark.”
4. Perform locking tests for each switch machine when locking is required.
5. Ensure locking test procedures so that employees can verify that power is removed.
6. Ensure that employees are trained to verify that either machine and the 3W/4W controller key switch or plug is in the proper position or that the switch machine controller is replaced.
7. Ensure all lights on top of the machine controller are dark before trains move over the switch.

The FRA states it encourages “all railroad industry members to take actions consistent with the recommendations of this Safety Advisory.” Additionally, it encourages those in the industry to “seek input from their workforce as the industry prepares to act the recommendations of this Safety Advisory.” This Safety Advisory may be modified in the future, or the FRA may issue additional Advisories to ensure safety on the railroads.

Safety Advisory 2025-01