question attempt- 2012-Q3

[tfly86]

Hi all, please see my attempt from the 2012 Mod 5 paper. this is question 3 on the paper which reads as follows:

Question 3 (2012)
Describe with the aid of diagrams the operation of the following two systems:

• Joint less track circuit
  
• axle counter system [15 marks]
  

What are the advantages and disadvantages of each system? [10 marks]

Please can you provide comment.

Regards

Tommy

[Jerry1237]

A few comments.

TCs should not be relied upon to detect broken rails and it should not be used as a pro or con for anything.

It would appear there is some mixing of terminology and understanding for the EBI section. From memory, the Tx sends a frequency out that the Rx interprets and if the Rx is receiving the correct frequency, the track is clear. A train shorts the track and stops the Rx seeing the frequency and hence goes occupied.

Voltage/current applies to other non-audio track types where shunting would drop a track relay.

Answer is heading in the right direction and the format is good.