Computerized System Integrity Tester (SIT)
System Integrity Test is conducted on Railway Signalling Systems to ensure Safety & Availability. The test is highly automated by which human errors are eliminated. Evidence of test results is produced for further validation, if required.
DESCRIPTION
Testing of Signalling System for compliance to TOC / RCC is mandatory before commissioning of any signalling system. After commissioning also this test is required to be carried out periodically once in 3 years. First test is offline and the second one is online.
Implementation of interlocking (based on SIP) has the following stages
- Preparation of Route Control Chart (RCC)
- Design of logic circuits
- Wiring of logic circuit
- Testing and commissioning
We have automated the testing by which it is possible to find the mistakes in last 3 stages i.e. Design and Wiring of circuits and Testing.
- The conventional (manual) system has the following limitations
- Test procedure is not fully defined
- No document of Testing (Test plan)
- No evidence of Test Results
- No evidence of validation of test results
- No scope for verification of tests done, since no tangible output, results out of testing
ARCHITECTURE
TYPES TESTS CONDUCTED
- Negative test of controlling functions
- One Signal One Train Test
- Route Checking Test (In Offline only)
- Route release test - light engine and long train
- Test for route locking
- Test for back locking or route holding
- Test for approach locking
- Red-lamp protection test
- Aspect sequence control test
- Lamp cascading test
- Point track locking test
- SMKEY locking test for different assets
- Crank handle and LX Gate locking test
- Square sheet test(In Offline only)
- Point Operation in Route Test (In Route setting type Panels Only)
PROCESS OF TESTING
- Representation of Table Of Control in terms of data logger inputs
- Instructions for carrying out tests are defined
- Tests are converted to a software program based on Table of Control
- Desirable test results are generated by software program based on Table Of Control
- Online test results are compared with desirable results through software program
- Status of the required relays are taken by the system from Data logger
APPLICATION AREAS
Railway Signal Interlocking testing in Online & Offline for
- Panel Interlocking ( PI )
- Route Relay Interlocking (RRI)
- Solid State Interlocking (SSI) / EI
