(07-10-2015, 06:57 PM)PJW Wrote:(07-10-2015, 06:54 PM)PJW Wrote:(07-10-2015, 09:12 AM)hariram Wrote:(07-10-2015, 06:39 AM)Hi Peter,I am sharing few more information to resolve the confusion between TTU/ETU/TC or TU/ETU/TCU. Wrote: I too have little knowledge of AFTC working. Here i am stuck up with TCU i.e Track Coupling Unit testing.
Attaching file for better understanding.
(07-10-2015, 04:51 AM)hariram Wrote: Hi Peter
Thank you for all information !!!
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Now with the above information I am testing TCU but ideally i have no idea what should be the load,as it is directly connected to Track. Secondly as TCU has single side track its load should be half of TU.
I need more information regarding TCU testing in ideal condition.
Thanks
Hari.
From the picture you helpfully attached, I am a little bit confused and will need to check the literature.....
It does sound as if you are using the equipment in a configuration with which I am not familiar.
You are probably right; in my days the TI21 could only be used as a double rail track circuit.
However I do know that it can now be used through pointwork as a single rail track circuit but do not know what components are required for this; I shall have to bring my knowledge up to date and respond to you later.
But in the meantime, I still don't actually understand precisely your use of the word "load".
I agree that the track circuit would form the electrical load for the transmitter as seen via the various transformers etc. so I have no problem with the term in that context; however I do not comprehend why you would need to know its value when testing the track circuit set up. Please explain further.
I have discovered that I have a copy of the Bombardier manual for EBItrack 200 single rail application (M580000626A4) at Issue 3 of June 2010 which I am pretty sure is now well out of date, but I imagine in many things still actually correct.
I have skim read it and whereas it confirms that TCUs have various advantages compared with ETUs (including having all the electronic equipment in the locations well away from the track) I don't think that it has anything that can help answer your question.
I have included a few small extracts from some relevant diagrams in case they are of interest.
PJW