AWS/TPWS relay unit

[jamieP]

Hi all would anyone be able to tell me if the AWS/TPWS relay unit fitted to hertiage traction deals with the AWS timing before a brake application is made or is the AWS timing reservoir and 3 second choke still fitted?

Thanks in advance.

Jamie

 

[Smudger105e]

Hi all would anyone be able to tell me if the AWS/TPWS relay unit fitted to hertiage traction deals with the AWS timing before a brake application is made or is the AWS timing reservoir and 3 second choke still fitted?

Thanks in advance.

Jamie

If you are talking about the green relay box, this is not the TPWS control box. The relay box (AFAIK) does not provide the delay for the application of the brakes. This is done by valves outside the relay box and uses variations on control, one is a timing reservoir with a choke fitted.

 

[jamieP]

If you are talking about the green relay box, this is not the TPWS control box. The relay box (AFAIK) does not provide the delay for the application of the brakes. This is done by valves outside the relay box and uses variations on control, one is a timing reservoir with a choke fitted.

That dosnt sound right to me with a modern setup. For example I think most mainline 47s are now fitted with a electric horn instead of a air one. And under a TPWS brake demand there is no timing delay unlike the AWS so the timing reservoir would need to be removed from the Baldwin EP valve.

 

[No Fault Found]

That dosnt sound right to me with a modern setup. For example I think most mainline 47s are now fitted with a electric horn instead of a air one. QUOTE]

Really? Sounds odd