RAILWAY DESIGNING OF RELAY LOGIC PRESENTATION
While designing the logic circuits conditions imposed in the control table are to be followed
Following guidelines are to be to be followed for various types of relay logic circuits.
* What is a meshed circuit and what are the risks factors to be considered?
* Special measures to retain a stored information during a power failure
* What is a stick circuit?
* Bridge paths
* Use of latched relays and types
* Polarized circuits.
* Necessity of time delay circuits and their application
* Various timing devices
* Timing problems in relay sequence.
* Designing of capacitor net work.
* Various types of proving and necessity.
* Down proving of relays in vital circuits.
* Various types of Cross proving of relays for conflicting functions and exemptions.
* Polarised circuits with biased relays
* Correspondence proving
* Sequence proving Use of repeat relays and care in using their contacts. Proving of their back contacts
* Provision of multiple track repeat relays
* Delayed response of track functions
* Electrical isolation
* Limitation on length of circuits
* Safeguards with polarised circuits.
* Change over paths in meshed circuits
* Indication circuits