The main architecture of the LOPS comprises a point machine, a control unit, a PPI and a plunger for operation.
The system also boasts a modular design philosophy which is created from high grade industrial components, thus increasing the availabilty of spare parts and reducing maintenance costs. The system is constantly performing self-checks on the circuits and reporting faults, which means that malfunctioning units can be swapped very quickly and easily. The metal plates on the front (see figure 3) can be taken off, exposing the logic controller hardware board, known as a card, beneath. This card has a part number and pin-code, meaning only a card of that type can replace the original.
All systems are compatible with relevant EU EMC standards to all traction types. All outdoor equipment has a temperature operating window of at least -25°C to +45°C or harsher.
Figure 2 – Tie-FenLock 100 basic layout
The Tie-FenLock 100 system can either be installed in a post-mounted cabinet or in a location cabinet.
A small post mounted (see figure 3) single cabinet can accommodate enough cards to control a single ended set of points. A large post-mounted cabinet can accomodate enough cards to control a double ended set of points.
A location cabinet can be used to house the equipment for multiple point ends in areas where turnouts are densely populated. Unlike typical NR location cabinets, these are mounted on a swinging frame and therefore necessitate access from one side. The frame is made up of 2 columns of 8 19” racks (although typically only a maximum of 7 are used to allow cable bending and access in the base of the location), on which the cards to control and process wayside information are mounted.
The racks are also compatible with indoor application, where a glass fronted cabinet can be mounted within a designated building or within a relocatable equipment building (REB).
The Tie-FenLock 100 system uses low maintenance, trailable point machines which are robust and mounted in the four foot. The machine has been installed in approximately 80 minutes which is much faster than current mainline equipment. It is mounted on two crossmembers which clamp to the outside foot of the rail. The overall height of the machine is below the standard BS113 rail running height.
Figure 4 – Point machine installation
The detection and power is supplied by a single cable, with a minimum of 5 cores. The power supply is currently a three phase neutral 400Vac supply, although a 110Vac varient is in development. It is recommended that the tail cable to the point machine is armoured to prevent damage.
The points machine features an internal mechanism allowing the machine to be safely used in a trailing direction without damaging the components. The machine can be installed with a plate which allows the intergration of a standard six-foot mounted back drive. In the event of a power failure, the machine can be operated manually by inserting a key to engage manual operation and then turning a crank handle.
The machine requires minimal maintenance at an interval of every 6 months, which is limited to the exterior of the machine. This is normally to account for vibration and for the wear in the turnout. It also includes adjustment of the detection rods and maintenance of the screw thread to prevent rusting, in addition to re-torquing the bolts.
Points Position Indicator (PPI)
The PPI is a two sided, three aperture LED indicator which is capable of showing two positive indications. The first is the straight ahead route, with points correctly set. This is shown as two vertical white lights. The second is for the diverging route, which is two horizontal lights. When the points are in the process of moving, the “new” position indication lamps flash in an out-of correspondance state until detection is achieved.
In the event of a failure, the PPI shall flash in this out-of-correspondance state until detection is achieved. This may occur if:
There is a blockage in the points blades and the machine motor times out;
Detection is lost after detection is made;
Loss of communication with the machine (power failure or cable break).
Separation between the cable for the plunger and other cables is required. This can be achieved by running the cables in separate troughs, providing 50mm separation between the cables within the trough, or providing a non-conductive barrier between the cables.
The Tie-FenLock 100 requires a three phase neutral 400Vac supply to the equipment housing, location or REB where it is transformed down and/or distributed as required. The electronic components predominantly run off 12Vdc and 24Vdc.
The Tie-FenLock 100 system is compatible with most points heating systems. However, should control of the points heating system be required by the depot operator, a more advanced version Tie-Fenlock 300 or 400 is required.