Smart Lock 400
Smart Lock 400
Smart Lock 400
This brochure lists the major similarities and differences between a Solid State interlocking (SSI) and Smartlock 400 (SML 400) system.
It is provided as a source of information to assist those already familiar with UK SSI architecture in their understanding of the features of Smartlock 400.
Single SSI with Signallers Entrance/Exit (NX) Panel & Local Trackside Communications The simplest SSI architecture is illustrated in Figure 1. This shows a typical small scheme, with the signaller and SSI interlocking co-located and the trackside area of control in close proximity, allowing the trackside equipment to be controlled via dual trackside data links using Data Link Modules located inside the SSI cubicle. The trackside data links may be diversely routed to counter the threat of simultaneous malfunction of both links owing to a common cause.
TRAIN DESCRIBER
PMUX
TECH TERM
TFM Network
Figure 1 Single SSI with Signallers Entrance/Exit (NX) Panel & Local Trackside Communications.
TRAIN DESCRIBER
PMUX
EQUIPMENT ROOM
IMnet
Support System Maintenance Signalling Technician Incident Investigation
I/O Channel 1
I/O Channel 2
F/E N
F/E R
CC1
CC2
CC3
GW A
GW B
2003
DLMs
TFM Network
Multiple SSI with Visual Display Unit (VDU) Signalling Control System & Remote Trackside Communications
Figure 3 shows a typical SSI arrangement used where a VDU based signalling control system (ICONIS, MCS, IECC) is used to control multiple SSIs whose trackside equipment is sufficiently remote to require access via Long Distance Terminals (LDTs). LDTs may also be used where the trackside equipment is close, but the diverse data link is fed from the remote end to improve availability. Access to the remote end is often most economically achieved via a telecom network. The LDT is designed to operate via a network offering a G703 standard interface.
x2
TECH TERM
PCM Network
LDT
LDT
LDT
DLM
DLM/TFM Network
DLM
DLM
DLM/TFM Network
DLM
Figure 3 Multiple SSI with Visual Display Unit (VDU) Signalling Control System & Remote.
SERVER
I/O Channel 1
I/O Channel 2
F/E N
F/E R
CC1
CC2
CC3
A1
B1
A2
B2
2003
N/W Interfaces
DLM/TFM Network
DLM
DLM/TFM Network
DLM
Figure 4 Smartlock 400 with VDU Signalling Control System & Remote Trackside Communications.
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Mode 2 (Warm) Enforced where mode 1 is not enforced (not a lengthy power out and at most one difference in the technicians controls), but significant differences in some flag memory states. Flag states over which there are differences are forced to the most restrictive state, but the interlocking comes on-line automatically after a time delay. Mode 3 Permitted where neither of the other modes is enforced (few differences in only certain flag memories permitted). The interlocking continues without interruption, forcing those flag memories where there were disagreements to the restrictive state.
Functionality
Start Up SSI has 3 modes of start up:Mode 1 (Cold) Enforced when the system detects extended power out or more than one disagreement between the preserved states of technicians controls. This mode requires confirmation from a technician to start up allowing the technician to re-apply controls having consulted a paper log.
Smartlock 400 permits an equivalent to modes 1 and 2. It protects from power outage and permits hot swap board replacement.
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SSI introduces an average cross boundary route setting delay of 4 seconds, with a maximum of 8 seconds (excluding point operation times). These times increase to 8 seconds and 16 seconds respectively if a route crosses 2 interlocking boundaries. Smartlock 400s ability to manage larger areas avoids such delays and permits boundaries to be chosen at less time-critical locations.
A Smartlock 400 system can cover an area equivalent to 6 panel SSIs, or 8 if controlled by a VDU based system. This number will increase with the future introduction of Smart I/O.
Maintenance Issues
Diagnostic Smartlock 400 diagnostic information is made available to maintainers remote from the interlocking cubicle via standard communications networks. On-line Repair Similar to SSI, replacement of failed units in the central interlocking cubicle can be effected without taking the interlocking off-line.
Data Recording
It is possible to perform a live search back through 28 days of recorded history of the systems behaviour and copy parts of the history onto media, for offline analysis, such Key response times between an SSI and that it cannot be altered and will survive 5 SML400 interlocking are similar. For SML400, years storage without degradation. the average time to revert a signal to danger The SSI log is typically shorter than 28 days. in the event of a change of trackside input state is less than 2 seconds. The maximum time is less than 4 seconds.
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System Configuration
The main differences to an SSI scheme are summarised below. The initial stages of the process for configuring the central interlocking data is the same as those used for SSI. SSI source files are initially prepared using the current automated tool, then completed using a text editor tools to add customised data. The desk check is soon to be assisted by a PC simulation of the logic at this time, rather than by visual inspection alone as is currently the case for SSI. Pre-processing of the original SSI source files expands some of the special constructs into multiple standard constructs. A compilation stage follows to produce data that can be executed by the Smartlock 400 system. Similar to SSI, a diverse de-compiler is used to provide verification that the compiler has not introduced errors. The physical media onto which the whole interlocking application is prepared for
insertion into the interlocking is a set of 3 USB memory devices (rather than the EPROMs used for SSI). The contents of the USB devices are diversified, forcing differences in software execution between
channels to improve safety. Unlike SSI, the USB devices contain the fixed interlocking and operating system software, as well as the scheme specific data. Automated testing on a target platform is provided to catch errors early and boost confidence following changes. Formal principles testing is undertaken on a target system with external simulation, rather than the Design Work Station (DWS) as for SSI.
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As with SSI, a separate mechanism is provided to check the interlocking identity and version number, to prevent incorrect or old data, or data for the wrong scheme from being used by mistake. The TFM Gateway components must also be configured. There is no directly equivalent process for this with SSI, which employs connector looping to set scheme specific addresses on the LDTs. Tool support is provided in the future for scheme design: Scheme Plans, Control Tables, CAD Design for build and trackside installation, linked to the interlocking configuration data.
RAMS Performance
The main improvements in availability are driven by improved, remote diagnostic facilities to speed mean time to repair of failed components.
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Signalling Solutions Limited Borehamwood Industrial Park Rowley Lane Borehamwood Hertfordshire WD6 5PZ Telephone: +44 (0) 20 8953 9922 Facsimile: +44 (0) 20 8905 1085 www.signallingsolutions.com
Prices are correct at the time of publication. Signalling Solutions Limited reserve the right to change specifications and prices. Issue 3 August 2010
Designed & produced by Anderson Lambert +44 (0) 1582 754000 www.andersonlambert.com