Signalling question - slotted distants

[Joseph_Pestell]

I understand the basics of slotted distant signals i.e. Signalbox B's distant is linked to Signalbox A's starter/advanced starter on the same post/doll so that the distant can not be "off" when the starter is "on".

 

But I don't know how it works. Now in some ways this does not matter on a model since I will be doing it electrically not mechanically. However, in the location that I am modelling, I think that Signalbox B would have a closing out switch and only be manned part-time. So, with box B closed out, the distant should be permanently "off" but that seems in conflict with the slotting. Surely it can't be the case that Signalbox B has to be open all the time that Signalbox A is open?

[Grovenor]

The slotting is done by the balance levers on the signal post, so irrelevant whether the box is open or closed.

Regards

[Joseph_Pestell]

The slotting is done by the balance levers on the signal post, so irrelevant whether the box is open or closed.

Regards

So, just to be clear, when box B is closed out, the distant arm would go up and down in synch with the starter???

[corneliuslundie]

Yes, essentially, when both signalmen have cleared their levers the weight on the balance lever for the distant can then drop and pull it off. As soon as one signalman returns his signal to normal it pushes the balance lever back up and the distant goes back to on. I am sure there has been a photo of just such a mechanism on this website in the last couple of weeks.

Jonathan

[beast66606]

It's all done mechanically (or electrically but thats a lot more obvious as in essence it's a "simple" matter of linking the distant motor to the lever via a switch closed by the stop arm)

 

The signal box controlling the distant(s) signal(s) does not have to be open, the distant arms will "lower" (show off) when the stop arms are cleared.

 

In simple terms

 

There are 3 weights involved, the centre weight which drops and moves the distant arm requires both other weights (one controlled by the stop arm and one controlled by the distant lever) to be "pulled" for it to drop and clear the distant arm, when either of these weights is replaced the distant arm also returns to caution.

In your case the distant lever weight would be semi-permanently raised so each time the stop signal was cleared, the distant would go with it.

 

I'm sure someone will have a drawing to explain it better.

 

Slotting can get very complicated when there are lots of boxes close together (and use more than the 3 weights mentioned) but the general principle of a weight controlling the arm, which requires other weights to be raised still holds true.

[Joseph_Pestell]

Many thanks to all of you.

 

I will be doing it electrically but at least I now know that I can close one box (which on stage one of the layout will mean that I can actually leave all but one of the signals "off"). Just need to work out the circuit now....

[beast66606]

Many thanks to all of you.

 

I will be doing it electrically but at least I now know that I can close one box (which on stage one of the layout will mean that I can actually leave all but one of the signals "off"). Just need to work out the circuit now....

 

I once made a 4mm model of a Wirral area signal with working mechanical slotting using clear thread and blue tack for the (hanging under the baseboard) various weights !

 

Electrically it's easy.

[The Stationmaster]

If you need photos of the sort of slot described by Beast (a drop off slot) I can supply and they are posted already on another thread (it would help if I could remember which thread of course  )

[Swindon 123]

Here is an example of a motor operated slotted distant signal, on a wire worked stop arm as mentioned by Beast in post 5. This example is at Shrewsbury and has Sutton Bridge Junctions Down Distant slotted to Severn Bridge Junctions Down Hereford Section signal. As far as I know, this signal has not been replaced yet.

 

 

A closer look at the motor working for the distant and wire for the section signal.

 

 

 

 

Paul J.

[iands]

A couple more photos showing the balance weights, I realise they do not give a totally clear idea on how they work. I did once have a diagram(s) from Basic Signalling course from many years ago which showed how the balance weights worked (interacted with each other), but all I have at the moment is a description of how they work which is pretty much the same as has been posted above. If I can find the diagram(s) I'll post on here for you.

 

Regards, Ian.

 

 

[18B]

the most interesting one however was at Pinton which had Sleights East distant (a two aspect colour light) on its starter. When Pinxton starter was on, Sleights colour lights weren't lit. when Pinxton's starter was off, it showed a black aspect (lens painted over) and Sleights distant lit up yellow! when Sleights cleared its starter (a colour light) then the distant changed to Green.............. when Pinxton put his start back on, the lights went out and Pinxtons starter showed a red aspect.