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| Brown barrier control levers 27/05/2018 at 16:45 #108293 | |
TUT
532 posts |
I hope you don't mind the flood of questions. I was just wondering about the operation of brown barrier control levers. From what I can tell they're a bit like FPLs on level crossing barriers in that you must reverse the lever, then operate the barriers by means of a wheel, or a button or your own strong arms and legs, and then when the barriers are secured, normalise the lever to lock them once more. Is this correct? The reason I ask is not just for confirmation. If I'm correct, is there any kind of check or interlocking to prove that the barriers are actually lowered for road traffic? Only it seems that mechanical interlocking at least would have no way of checking that you'd actually moved the barriers, or even that you'd cycled the lever between reverse and normal, and at least as far as the interlocking was concerned, you could pull the signals off without troubling with the barrier control lever or the barriers themselves at all. Are there any additional checks on the position of barriers in mechanical signalboxes? Log in to reply |
| Brown barrier control levers 27/05/2018 at 17:33 #108295 | |
headshot119
4869 posts |
I can't speak for mechanical gates. But for electronic barriers the level is normally electronically locked normal in the frame until the barriers are proved down, is it then electrically released to go reverse. The signals are then interlocked with the barrier level mechanically. "Passengers for New Lane, should be seated in the rear coach of the train " - Opinions are my own and not those of my employer Log in to reply |
| Brown barrier control levers 27/05/2018 at 17:49 #108297 | |
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jrr
95 posts |
On the heritage railway I am a signalman for we have a set of gates operated with two (brown) levers and a wheel. The signals across it are mechanically interlocked and cannot be operated until the second lever is operated and the gates are locked closed to vehicles. The levers also lock/release the wheel. As the gates are next to the box checking visually is almost automatic.
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| Brown barrier control levers 27/05/2018 at 19:47 #108299 | |
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Stephen Fulcher
2078 posts |
On Western installations you normally reverse the lever to raise the barriers.
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| Brown barrier control levers 27/05/2018 at 22:52 #108303 | |
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Late Turn
699 posts |
I’ve worked boxes with the barrier lever normal with the barriers raised (“barrier locking lever” usually) and others where it’s reversed with the barriers raised (“barrier release lever”), and the principle is the same either way - the lever is electrically locked until the barriers are proved down, at which point it can be reversed/normalised to allow signals to be cleared; it’s then mechanically locked in that position until the signals are back at danger (and approach locking timed out etc.) and the barriers can’t be raised until that’s done.
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| Brown barrier control levers 27/05/2018 at 23:20 #108304 | |
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TUT
532 posts |
Thanks everyone! That makes a lot more sense now! :) I might as well come clean and admit I chose to use Prees, Wem and Harlescott Crossing as examples in a little article I wrote (purely for my own interest) about absolute block signalling. Wem lost its barrier control lever at some point by the looks of it, but what about Prees and Harlescott Crossing, does anyone know how the barrier control levers worked in those boxes. From photographs I'm guessing the levers were normal with the barriers raised. Log in to reply |
| Brown barrier control levers 29/05/2018 at 22:45 #108338 | |
Ar88
310 posts |
The DFR (Dean Forest Railway) uses 3 brown levers in it's Lydney Junction (ex-Heysham Harbour) box. 2 to lock/release the manual wicket gates (platform-exit), 1 to prove locking on the level crossing barriers! The Welsh contingent. Aron, or Ar to mates. Also known as 88E or ThatManCalledAr. Log in to reply |
| Brown barrier control levers 30/05/2018 at 09:22 #108340 | |
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kbarber
1742 posts |
TUT in post 108293 said:I hope you don't mind the flood of questions.Going back to older technology, there were often 2 brown levers (in addition to wicket gates) plus a gate wheel(s). One of the levers was called gate stops and the other was the gate lock. The gate stops were like a sprung catch on the road surface (with a 'rising' mechanism so they were normally flush but rose as the gates swung towards them), to hold the gates in either the open or closed position (where open means for the railway of course :-) ). To work a crossing of this kind, the first step was to operate the gate stops lever. That lowered the stops holding the gates closed and armed the stops for the open position. Then wind the wheel; as the gates open the 'open' stops rise out of the road - by this time there should (!!) be no traffic to get caught on them. As the gates reach the fully open position, they ride over the stops and are then held in place. It is now possible to operate the gate lock - it will not come fully over unless the gates are in the fully open position, so there's no issue with being able to work it with the gates set 'wrong way'. To close the crossing, just do the whole thing in reverse. Log in to reply The following user said thank you: TUT |
| Brown barrier control levers 30/05/2018 at 14:04 #108341 | |
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clive
2789 posts |
kbarber in post 108340 said:Not disagreeing with anything that Keith said here, just adding a note: there's quite a complicated mechanism to ensure that the gate is, and STAYS, behind the gate stops before you call pull the lever. The naïve approach doesn't work because, if the gate is moving fast, it can bounce off the post and back over the stop before the latter has had time to rise behind it. So the stop mechanism thinks it's holding the gate but in reality the gate is in the wrong place. Log in to reply The following user said thank you: kbarber |
| Brown barrier control levers 30/05/2018 at 15:12 #108343 | |
Giantray
347 posts |
I used to work Cuxton SB on the Medway Valley. This had a Brown Lever to lock the gates, but did not have gate stops that would rise out of the ground. The gates were shut manually, each of the two gates would be closed and a long metal bolt would be lowered and inserted into the "bottle" in the ground and turned and locked. The Brown Lever then would be operated which would then lock and prevent the long metal bolts from turning. In the open position there was just a secure housing that the long metal bolt could be lowered into to hold the gates open. The "bottle" required the bolt to be inserted and turned to enable the Brown lever to be moved to lock the gates, otherwise the Brown Lever was locked by the position of the "bottle". I never actually saw what the "bottle" looked like because it was hiddened in the ground. Professionalism mean nothing around a bunch of Amateur wannabees! Log in to reply The following user said thank you: BarryM |