ryan125hst
Established Member
Back in the days of steam, carriages were coupled using buffers and a chain or by a Buckeye Coupler (Buckeye between coaches and buffers and a chain for the loco? Im not 100% sure on the mechanical connections). A vacuum brake pipe was used to provide a fail safe automatic brake throughout the train and a steam heating pipe allowed steam from the locomotive to be piped throughout the train to heat the carriages in winter. This continued for early diesel locomotives as they were fitted with vacuum brakes and a diesel power steam heating boiler to allow the carriages to be heated in the same way as before.
By the late 1960s and into the 1970s, locomotives and carriages were fitted with a two pipe air brake system and Mark 2A carriages didnt have vacuum brakes at all (the original Mark 2s and some Mark 1s were dual brakes). In the early 1970s trains were increasingly becoming electrically heated, due to the presence of a large diesel generator on the front of every train no doubt! Early Mark 2s simply had electric heaters whereas later models also had air conditioning and relied on the Electric Train Supply for charging the batteries to power the lights as well (coaches used to use a wheel driven dynamo for this purpose). The Mark 3s and 4s now rely on ETS for their lights, heating and air con, cooking and power sockets.
So, a British Rail Mark 1 carriage that is dual braked and dual heated would have a mechanical coupler, a vacuum brake pipe, two air brake pipes (automatic air brake and main reservoir), steam heating pipe, two Electric Train Supply cables and finally two RCH (Railway Clearing House) cables to allow the guard to switch the lights throughout the train on and off from one place (these cables are now also used for Public Address and for remote control signals to the locomotive on push-pull trains).
As you can probably see, I enjoy learning about these technical aspects as Im not old enough to remember the BR Blue era never mind the steam age yet can tell you all I have said above.
With this in mind however, theres a couple of photos Ive seen lately that has confused me:
First of all, this photograph of a Mark 1 coach shows a second electrical jumper cable, the one that is positioned vertically and not diagonally as with the ETS cable. The cable is a lot thinner than the ETS cable and there also appears to be a socket on the left hand side of the coach to the left of the red air brake pipe but to the right of the ETS socket. Does anyone know what it is?
Secondly, what is that thinner cable on this Caledonian Sleeper Mark 3? Again, theres a smaller socket that is to the right of the ETS socket (the former is a lot cleaner than the latter). Theres then a thin cable with a connector visible beneath the left buffer and a thin cable can also be seen to the right of the coupler. Note the thick ETS cable, so its definitely something different. This second photo provides another angle if that helps you. Does anyone know what it is for? Is this the same thing as on the Mark 1? It looks like there are two additional connections here, one which, like the ETS connection, has a cable plugged in to a dummy socket and plugs into a connector, but that cable beneath the left buffer then appears to be something else.
Can anyone shed any light on this?
Many thanks
Ryan
By the late 1960s and into the 1970s, locomotives and carriages were fitted with a two pipe air brake system and Mark 2A carriages didnt have vacuum brakes at all (the original Mark 2s and some Mark 1s were dual brakes). In the early 1970s trains were increasingly becoming electrically heated, due to the presence of a large diesel generator on the front of every train no doubt! Early Mark 2s simply had electric heaters whereas later models also had air conditioning and relied on the Electric Train Supply for charging the batteries to power the lights as well (coaches used to use a wheel driven dynamo for this purpose). The Mark 3s and 4s now rely on ETS for their lights, heating and air con, cooking and power sockets.
So, a British Rail Mark 1 carriage that is dual braked and dual heated would have a mechanical coupler, a vacuum brake pipe, two air brake pipes (automatic air brake and main reservoir), steam heating pipe, two Electric Train Supply cables and finally two RCH (Railway Clearing House) cables to allow the guard to switch the lights throughout the train on and off from one place (these cables are now also used for Public Address and for remote control signals to the locomotive on push-pull trains).
As you can probably see, I enjoy learning about these technical aspects as Im not old enough to remember the BR Blue era never mind the steam age yet can tell you all I have said above.
With this in mind however, theres a couple of photos Ive seen lately that has confused me:
First of all, this photograph of a Mark 1 coach shows a second electrical jumper cable, the one that is positioned vertically and not diagonally as with the ETS cable. The cable is a lot thinner than the ETS cable and there also appears to be a socket on the left hand side of the coach to the left of the red air brake pipe but to the right of the ETS socket. Does anyone know what it is?
Secondly, what is that thinner cable on this Caledonian Sleeper Mark 3? Again, theres a smaller socket that is to the right of the ETS socket (the former is a lot cleaner than the latter). Theres then a thin cable with a connector visible beneath the left buffer and a thin cable can also be seen to the right of the coupler. Note the thick ETS cable, so its definitely something different. This second photo provides another angle if that helps you. Does anyone know what it is for? Is this the same thing as on the Mark 1? It looks like there are two additional connections here, one which, like the ETS connection, has a cable plugged in to a dummy socket and plugs into a connector, but that cable beneath the left buffer then appears to be something else.
Can anyone shed any light on this?
Many thanks
Ryan