Signal Boxes - different regions / companies

[Llanigraham]

I received and sent 6 once in my years, and neither time was "Call to Attention" sent.

 

[Rescars]

Deleted

 

[Mr. SW]

In the days before computing, how did power boxes for, say, Multiple Aspect Signalling areas, communicate with mechanical boxes, and vice versa?

 

[Gloster]

In the days before computing, how did power boxes for, say, Multiple Aspect Signalling areas, communicate with mechanical boxes, and vice versa?

It developed over the years, but the track circuits supervised by the ‘power box’ would run right up to the fringe box so that there was no empty area for a train to go missing in. For one to advise the other of what train (type or destination) they employed the latest technology. Early on this would just be describing by bell codes as before, but this was just telling the box what was coming, no asking for Line Clear or sending Out of Section, etc. Gradually they went through simple clock type train-describers and more and more sophisticated ways for the fringe box to input the four-character description so that the train could pick it up automatically when it hit a certain track-circuit. I worked at different times with describing both ways by bells, elderly machines where the headcode had to be dialled up on a ‘phone type dial and modern push-button ones. However, the bell was always available for emergency use.

 

[Dr Hoo]

It developed over the years, but the track circuits supervised by the ‘power box’ would run right up to the fringe box so that there was no empty area for a train to go missing in. For one to advise the other of what train (type or destination) they employed the latest technology. Early on this would just be describing by bell codes as before, but this was just telling the box what was coming, no asking for Line Clear or sending Out of Section, etc. Gradually they went through simple clock type train-describers and more and more sophisticated ways for the fringe box to input the four-character description so that the train could pick it up automatically when it hit a certain track-circuit. I worked at different times with describing both ways by bells, elderly machines where the headcode had to be dialled up on a ‘phone type dial and modern push-button ones. However, the bell was always available for emergency use.

I was quite surprised when visiting London Bridge power signal box, must have been in the late 1990s, when Six Bells suddenly rang out. It transpired that Addiscombe had had a derailment in the station throat during a shunt move.

 

[ChiefPlanner]

Oddly enough , last week down in St Albans box (the restored one) , out of curiosity I banged out 6 bells on the simulator to pretend Napsbury "box" , - after a few seconds I got a clear and steady "6" back.

A very safe way of doing it ! (this was on the up slow) ........

 

[norbitonflyer]

I am sure I have seen illustrations of boxes equipped with, for example, staffs for one section and tokens for the next.

After Abermule I understand there was a general trend to make the objects (staff/token/tablet) used in adjacent sections more distinctive.

(For those not aware, the cause of the head on collision near Abermule in 1922 was a misunderstanding between station staff, resulting in the driver of a train being given back the tablet for the section he had just traversed and taking it as authority to enter the next section, which was already occupied by an oncoming train).

 

[matchmaker]

It developed over the years, but the track circuits supervised by the ‘power box’ would run right up to the fringe box so that there was no empty area for a train to go missing in. For one to advise the other of what train (type or destination) they employed the latest technology. Early on this would just be describing by bell codes as before, but this was just telling the box what was coming, no asking for Line Clear or sending Out of Section, etc. Gradually they went through simple clock type train-describers and more and more sophisticated ways for the fringe box to input the four-character description so that the train could pick it up automatically when it hit a certain track-circuit. I worked at different times with describing both ways by bells, elderly machines where the headcode had to be dialled up on a ‘phone type dial and modern push-button ones. However, the bell was always available for emergency use.

There were a few cases where panel boxes operated Absolute Block to an adjacent mechanical box - two examples were Motherwell and Aberdeen. I can't remember what box Motherwell worked to, but Aberdeen worked to Newtonhill in one direction AB. The other direction was TCB.

 

[D6130]

There were a few cases where panel boxes operated Absolute Block to an adjacent mechanical box - two examples were Motherwell and Aberdeen. I can't remember what box Motherwell worked to, but Aberdeen worked to Newtonhill in one direction AB. The other direction was TCB.

Not 100% certain....but I think Motherwell may have worked absolute block to Benhar Junction (East of Shotts) in at least one direction.

 

[Gloster]

There were a few cases where panel boxes operated Absolute Block to an adjacent mechanical box - two examples were Motherwell and Aberdeen. I can't remember what box Motherwell worked to, but Aberdeen worked to Newtonhill in one direction AB. The other direction was TCB.

There would be no problem about this as long as there were suitable arrangements for checking the taillight. I have seen it somewhere on a Domino type NX panel: just standard size indicator lights (ca. 3 mm. diameter holes) and a switch. To someone used to larger, solid block instruments it looked a bit fragile.

 

[matchmaker]

There would be no problem about this as long as there were suitable arrangements for checking the taillight. I have seen it somewhere on a Domino type NX panel: just standard size indicator lights (ca. 3 mm. diameter holes) and a switch. To someone used to larger, solid block instruments it looked a bit fragile.

That's what I remember at Motherwell - as you say, it looked a bit fragile!

 

[John Webb]

Oddly enough , last week down in St Albans box (the restored one) , out of curiosity I banged out 6 bells on the simulator to pretend Napsbury "box" , - after a few seconds I got a clear and steady "6" back.

A very safe way of doing it ! (this was on the up slow) ........

You beat me to it! I was fairly certain our 'chief programmer' had included it!

 

[Gloster]

Surely most sections would have had identical instruments at each end (otherwise the tablets/tokens/staffs wouldn't fit). [AMENDED] One variation would be the use of "no signalman" instruments which were operated by the guard or station staff. However adjacent sections might well have been equipped with different instruments. I am sure I have seen illustrations of boxes equipped with, for example, staffs for one section and tokens for the next. Tokenless block might have provided more opportunities for variations. Others will know much more.

Adjacent sections must have different configurations of staff/key/token so that it is impossible to put a staff back in the wrong instrument. That was simple enough on a single line with all boxes in circuit when the line is open: A - B - A -B - A and so on. But once you have boxes that can switch out for long-section working and branches, it becomes a bit more complicated. The standard key token instruments went up to configuration F (I think), with A and B normally being used, quite a few C and some D, but the last two were rare. In addition to the notch in the key or token, or rings on the staff, and the engraving, each type had its own colour.

No Signalman Key Tokens were just the same, but only needed a signalman at one end to give a release. The traincrew or station staff just removed or returned the token: they weren‘t involved in obtaining the release beyond making a telephone call.

It was quite possible for a box to work with one type of system in one direction and another in the other, unless it was a box that switched out: the two sections and their equipment were effectively entirely separate. Yeovil Junction had Tokenless Block on the Salisbury-Exeter line and key token to Yeovil Pen Mill. Tokenless Block didn’t have tokens so there was no risk of mixing them up: it was all in the electrics.

 

[Ashley Hill]

No Signalman Key Tokens were just the same, but only needed a signalman at one end to give a release. The traincrew or station staff just removed or returned the token: they weren‘t involved in obtaining the release beyond making a telephone call

At Eggesford drivers release their own tokens which is authorised verbally by signalman at Crediton.

 

[D6130]

At Eggesford drivers release their own tokens which is authorised verbally by signalman at Crediton.

The same applies at Battersby, Glaisdale and Whitby - plus the intermediate ground frame release at Grosmont - which is authorised verbally by the signaller at Nunthorpe.

 

[Ashley Hill]

There were a few cases where panel boxes operated Absolute Block to an adjacent mechanical box

This reminded me of some temporary arrangements in Exeter PSB during resignalling. AB to Exeter West.

Photographer not known.

 

[Cheshire Scot]

At Eggesford drivers release their own tokens which is authorised verbally by signalman at Crediton.

The same applies at Battersby, Glaisdale and Whitby - plus the intermediate ground frame release at Grosmont - which is authorised verbally by the signaller at Nunthorpe.

Does the signaller not also need to give a release as well as verbal authority? Otherwise there would be nothing to stop some unauthorised person taking a token out.

 

[Gloster]

I am not sure of the current rules as I have been out of it for nearly forty years. I think that there is a difference between No Signalman Key Token (NSKT), which has a box at one end, and No Signalman Key Token - Remote (NSTR), which is supervised by a box further away. However, my recollection was that in the mid-1980s there was little effective difference in the rules between the two, if the second (NSTR) actually existed; there may have been things included in the box’s instructions. I finished just before the mid-1980s wave of bringing in NSTR and there is nothing in my signalling regulations. My vague recollection of working Liskeard is that we effectively worked the normal Key Token (to Coombe Junction) and One Train Working (on to Looe) rules.

Does the signaller not also need to give a release as well as verbal authority? Otherwise there would be nothing to stop some unauthorised person taking a token out.

As said above, I have been out of it for a while and am not sure, but I think that the token on the remote sections is not released by the signalman and it would be possible for a third party to take a token out without permission. However, they could only do this if no token is already out and, if they did, no further token could be taken out. It is at least safe.

 

[edwin_m]

As said above, I have been out of it for a while and am not sure, but I think that the token on the remote sections is not released by the signalman and it would be possible for a third party to take a token out without permission. However, they could only do this if no token is already out and, if they did, no further token could be taken out. It is at least safe.

The machine would at least be in a locked cabinet.

Many years ago I was on the IECC support team, whose role included updating the software and data for commissioning phases of the re-signallings (by means of a large bag containing many silicon chips to be plugged in). This included various fringe box installations where our up to the minute (by 1980s standards) hardware sat alongside various brass levers and block instruments. One I particularly remember was the temporary fringe of Yoker signalling centre at Bowling. The night shift signaller, expecting no trains, was exceedingly grumpy at being woken up repeatedly by the terminal kept bleeping as it lost and regained contact as my colleagues at Yoker were taking the system off and on line. Another was in the 1930s LNER box at Darlington, where I asked why the keyboard was chipped and there was a screwdriver next to it. This was because ever since someone spilled lime cordial on it, certain keys would stick down until levered back up.

 

[Ashley Hill]

Does the signaller not also need to give a release as well as verbal authority? Otherwise there would be nothing to stop some unauthorised person taking a token out.

No. The machines at Eggesford are self release, you press the plunger and withdraw the token. The driver still requires verbal permission to withdraw one and the call is on a recorded line. The machines are in locked huts.

 

[Rescars]

Adjacent sections must have different configurations of staff/key/token so that it is impossible to put a staff back in the wrong instrument. That was simple enough on a single line with all boxes in circuit when the line is open: A - B - A -B - A and so on. But once you have boxes that can switch out for long-section working and branches, it becomes a bit more complicated. The standard key token instruments went up to configuration F (I think), with A and B normally being used, quite a few C and some D, but the last two were rare. In addition to the notch in the key or token, or rings on the staff, and the engraving, each type had its own colour.

Your mention of the complications of long-section working are well made. As an example, on the Portpatrick and Wigtownshire Joint, relevant boxes were equipped with parallel arrangements covering the same single line of route, typically Tyers No 6 instruments for normal (short-section) working to the next box and Tyers No 7 instruments for long-section working when the next box was switched out. This would presumably have ensured that there could have been no confusion between the various tablets.