Outdoor Signalling Maintenance

Newly soldered connections should not be touched until fully cooled.

Bend wires in a clockwise direction during termination.

Use wire strippers, not cutting pliers, to strip insulation.

Maximum two wires per terminal during termination.

Terminate multi-strand wires to terminal lugs and cover with insulation sleeves.

Signal Placement depends on sighting reports (engineers assessment).

Adjust signal height if needed for clear visibility.

Signals are typically placed on the left side of the track

If a signal must be placed on the right side of the track due to site limitations, it requires special approval and must be marked with an arrow pointing towards the relevant track.

A new signal not yet operational must be turned away from the track, unlit, and marked with an 'X' across it.

Existing signals must be inspected jointly by signal, traffic, and loco inspectors to ensure visibility and a certification issued. Action is needed to improve visibility as per recommendations.

If a signal post's implantation is less than standard dimensions, the infringing distance must be marked in red on a white background.

Colour light signals can be mounted on a rigid ground post or a signal gantry. Route indicators, Calling ON units, and Shunt signal units are provided as needed.

Each signal unit must be fixed rigidly in position and marked with a letter code that identifies the signal type (e.g., 'G' for ground signal, 'P' for platform signal).

Signal posts must be kept plumb (vertical) and packed with suitable material to ensure stability.

Each signal unit needs to be correctly aligned for optimal visibility.

The point machine should be placed away from potential obstructions and close to the switch, allowing for smooth movement.

Before installing a point machine, verify the track infrastructure (points, wiring, and drainage) meets the specified standards.

The point machine should be cleaned and lubricated according to the manufacturer's instructions before installation.

Ensure the point machine is properly aligned and leveled with the point gears for optimal function.

The sleepers supporting the point machine must be level and the ballast tamped to prevent sinking during train passage.

Wiring from the operating point to the location box should be in cable, with adequate protection for underground sections.

Crossovers should be operated by separate point machines, one at each end, with detection of setting and locking connected in series.

A mechanism should be in place to cut off the motor feed if an obstruction is detected, preventing damage.

The process of ensuring the detector contacts in a point machine accurately indicate the tongue rail position, both closed and open.

1. Manually close the tongue rail fully.
2. Insert a 1.6 mm gauge between the stock rail and switch rail, 150 mm from the switch toe.
3. Operate the point machine, ensuring detector contacts make.
4. Insert a 3.25 mm gauge at the same position.
5. Adjust the closed switch detector connection until contacts break.
6. Repeat steps 2-5 at the open end of the stroke.

A test performed during switch detector adjustment where the lock slide is in a simulated locked position, even if the machine isn't actually locked.

The friction clutch mechanism in a point machine allows the motor to slip under obstruction, preventing damage to the machine or track.

A test conducted by placing a 5 mm thick test piece between the switch and stock rail to check for proper functioning of the protection mechanisms.

Crank handles on point machines should be locked normally, but can be released for use in a point machine by a control on the control panel. This ensures safety and prevents accidental changes to routes.

Excess gaps around cable entry points in point machines should be plugged to prevent rodents and water from entering the machine.

Electric point machines should have gaskets and wire entrances sealed to make them watertight and dustproof. This ensures the machine's longevity and reliable performance.

Electric point machine covers should be locked, with separate locking mechanisms for the crank handle and cover.

The notches on locking, driving, and detection slides in point machines should not be tampered with or reconditioned. Worn-out slides should be replaced with new ones.

Before adjusting a point machine, it should be manually cranked by hand. This disconnects the power and allows for safe adjustment.

After fastening the point machine, the throw bar connections need to be adjusted and the machine cranked to both ends of the stroke.

The closed switch in a point machine should be adjusted to just touch the stock rail. Then the connections should be tightened further to provide a springing action to the tongue rail.

This test checks if the point machine can be locked with a 5 mm thick obstruction between the switch and stock rail. It ensures the safety system prevents lock-in when there's an obstruction.

The current needed to operate the point machine in both directions should be roughly the same. Unequal currents indicate problems like friction, poor packing, or lubrication issues.

The spring in the switch should be checked for adequate force. It shouldn't be too strong to cause excessive wear, nor too weak to hold the switch against the stock rail.

The friction clutch, where provided, should slip at the value specified by the manufacturer to protect the machine from overload.

Worn out pins should be replaced, holes reamed, and oversized pins fitted. Split pins should be properly split.

Regular checks of voltage and current at the motor terminals identify any undue friction or loose connections.

Periodic tests on cable and wire insulation and continuity ensure a reliable electrical connection.

The system should periodically check that the point's interlocking function is working properly. This ensures safety by preventing conflicting movements.