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Remote Operator for ETT 6

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Remote Operator for ETT 6

Unread postby Chris Osment » Fri Mar 30, 2018 10:14 am

Does anyone know please if anyone has designed and/or is using a 'remote operator' with Tyer's No 6 ETT instruments?
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Re: Remote Operator for ETT 6

Unread postby Richard Lemon » Fri Mar 30, 2018 10:51 am

Chris,

I do not think such is possible, due to the way the commutator physically locks the slide etc. This said, I'll be happy to be proved wrong!

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Re: Remote Operator for ETT 6

Unread postby Chris Osment » Fri Mar 30, 2018 11:11 am

Richard Lemon wrote:Chris,

I do not think such is possible, due to the way the commutator physically locks the slide etc. This said, I'll be happy to be proved wrong!

Richard


My initial thoughts too, but.....

To send a train from A (a manned box) to B (an unmanned box) , then IMHO essentially all that A needs surely is a remote release of the correct polarity from B? All the mechanical unlocking with the commutator is done at A. For a situation where the train takes a tablet from A to B, then returns to B without passing the tablet thru' the machine at B, but it is put back in at A, then it ought to be feasible.

The scenario where in effect they are 'no signalman' machines and both locations are unmanned, so A gets a release from B, but when the train with the tablet from A arrives at B then how is the machine reset at A, is another matter!
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Re: Remote Operator for ETT 6

Unread postby Richard Lemon » Fri Mar 30, 2018 12:27 pm

I suppose this might be possible, so long as the train just goes through the section and back again. But, easier to use Key Token!!!!
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Re: Remote Operator for ETT 6

Unread postby Chris Osment » Sat Mar 31, 2018 3:54 pm

Does anyone perhaps have a circuit diagram for a 'remote operator' for electric key token machines please?
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Re: Remote Operator for ETT 6

Unread postby MRFS » Sat Mar 31, 2018 3:58 pm

If this is required for the L&B, some of the S&T department are aware of the concept idea for an air main and pneumatic arm that was cooked up some years ago!

A purely electrical Remote Operator is difficult, but it is easy to wire up a release unit that will allow one tablet out to be returned to the same instrument it was abstracted from.
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Re: Remote Operator for ETT 6

Unread postby Chris Osment » Sat Mar 31, 2018 4:01 pm

>>>> but it is easy to wire up a release unit that will allow one tablet out to be returned to the same instrument it was abstracted from.

Roughly what I was thinking about for the moment - start with something simple!

I thought that looking at a circuit for EKT/ETS would give me an idea of what conditions needed to be checked before the release could be given.
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Re: Remote Operator for ETT 6

Unread postby MRFS » Sat Mar 31, 2018 5:35 pm

Basically the 'magic box' checks incoming current and returns polarity using the far end (i.e. where the magic box is) commutator to set the return polarity. This return pulse is timed via a capacitor to allow operation at the near end.

All the phase changing is done by the instruments themselves. That's the inherent limitation with No 6: needing to engage and disengage the commutator.

I'm sure a reversible No 6 RO is achievable but extra line wires would be needed - a one tablet out at one end and back in again from either end is no problem at all. Provided one end is always manned things should be OK, the problems come (from memory) once the tablet commutator is reversed at the remote end as at some point the commutator needs to be normalised with no-one there.


The other possibility is to completely rewire the instruments, replace the halved commutator with a quartered commutator so the tablet instrument could have two 'normal' positions like ETT and ETS.
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Re: Remote Operator for ETT 6

Unread postby Chris Osment » Sat Mar 31, 2018 5:45 pm

MRFS wrote:The other possibility is to completely rewire the instruments, replace the halved commutator with a quartered commutator so the tablet instrument could have two 'normal' positions like ETT and ETS.


But how would you cope with the mechanical linkage between the commutator and the left and right lock bolts? That's why surely the commutator has to move from left to right, then back from right to left, I'm not sure how you could arrange it to go 360 degrees....
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Re: Remote Operator for ETT 6

Unread postby MRFS » Sat Mar 31, 2018 6:37 pm

It was merely a concept.
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Re: Remote Operator for ETT 6

Unread postby Richard Lemon » Sat Mar 31, 2018 9:07 pm

I am sure that if this was really practical with No. 6s, Tyer or someone would have done it! Much easier to use KT or Miniature ETS!

But, there was No 8 hoppers (correct me if I have the number wrong) as on the C & M. These were really "No Signalman". Could some clever person make some?
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Re: Remote Operator for ETT 6

Unread postby Pete2320 » Sun Apr 1, 2018 12:16 am

If all trains are to run out and straight back then all that is needed is a means of providing a feed of the unchanging correct polarity so actually quite simple. However, apart from perhaps releasing the starting signal, what purpose would the tablet machine serve?
Equally if the remote end is a Signalbox that can often remain switched out, but it is properly manned when switched in it should be possible to do something along the lines of providing a permanent feed to the line wires when the box is switched out via (say) the king lever. By the nature of tablet machines this would not need to go through the commutator of the remote machine but some means of preventing the remote battery being on load at all times would be desirable. That said, AFAIA it was never done so perhaps it is more complicated than that.
Richard Lemon mentions that No8 machines were "no Signalman". I wonder if it might have been possible to adapt No4 machines with their electrically operated commutators to work as "no Signalman" instruments, amounting to MRFSs' suggestion!
At the end of the day I go along with the suggestion that if this was reasonably practicable Tyers would have marketed the equipment.

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Re: Remote Operator for ETT 6

Unread postby Pete2320 » Sun Apr 1, 2018 12:19 am

Chris Osment, it is suggested that this might be for the L&B. If so, what are the operational requirements.

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Re: Remote Operator for ETT 6

Unread postby Richard Lemon » Sun Apr 1, 2018 7:48 am

I suggest stick with One Train Working, saves complications.

Any complex / unusual arrangement will probably require "safety Verification" under ROGS by an ICP. Try to avoid this.

If electric token is required (and at this stage I still ask "Why?") use standard proven systems - Key Token or Miniature ETS.

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Re: Remote Operator for ETT 6

Unread postby Chris Osment » Sun Apr 1, 2018 10:42 am

Thanks for all the comments, but to be honest everyone has been making rather too much of a simple query.

It's been a wet few days, I was having a casual conversation with someone about ETT6 (they were interested in the details of how they worked), and we wandered onto a discussion of branch lines where normal block working (eg /TS&T/EKT/ETS) was reduced to OES at quiet periods. Somewhere along the way the question came up as to whether remote operators had ever been used anywhere with ETT6 - I didn't think so, but I though that I would ask just to be sure. After that, I started to wonder if I could design one......

Sorry if perhaps I should have made that clearer at the start, but I hadn't expected to start a few hares running....oops....
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