Author Topic: MERG and the "CBUS"  (Read 4339 times)

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Offline MikeWilliams

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Re: MERG and the "CBUS"
« Reply #15 on: March 07, 2016, 09:02:00 AM »
Sorry to be negative here and whilst I have experience of full interlocking on a permanent layout, I have no experience of this system or on portable layouts, but ...

Monkton Priors is a very simple portable layout capable of being extended in different ways.  I would keep it simple and have no interlocking and minimal electronics.  Consider manual point control at this stage - wire and tube is tried and proven, cheap and quick.

How does the complex electronics work and physically connect up if you suddenly add another baseboard in the centre with a new point and siding, or a couple more boards at the end?

Mike

Offline blagdon

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Re: MERG and the "CBUS"
« Reply #16 on: March 07, 2016, 11:35:20 PM »
I agree with Mike; 'KISS'.

'The Pirate'

Offline John Candy

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Re: MERG and the "CBUS"
« Reply #17 on: March 08, 2016, 07:04:00 AM »
Well, I would normally  go along with "KISS" (simple is best, I agree) but in this case, with lots of board joints (and longish distance to cover....the layout Monkton Priors layout will be 50 ft overall) there are difficulties with using mechanical means......not least "bridging" the board joints.

Whereas an electrical cable can simply be plugged and unplugged using multi-point (computer type) connectors, linking rodding is more complicated.

From the start, I had envisaged the turnouts and the signals being electrically powered by solenoid motors but (if it is affordable....and Ian T is working on that aspect) then using the CBUS (with servo motors of the type used with radio control) both simplifies the wiring and makes operation simpler (especially if the exhibition crew is limited in numbers).

There is also the fact that using digital control, the control panel diagram will indicate if a turnout has failed to "switch" fully thus avoiding unnecessary derailments. A bonus is that semaphore signals can simulate the "bounce" one sees when an arm drops.

Whether or not Monkton Priors goes digital remains to be seen...there are a lot of more pressing matters demanding attention.

In a garden environment, I am not convinced that CBUS (or any other PCB based system)would survive the weather but its use would very considerably reduce the amount of (long distance) wiring required.

Regards,
John.
 
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Offline cabbage

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Re: MERG and the "CBUS"
« Reply #18 on: March 08, 2016, 07:23:39 AM »
John...
Speaking as a "computer person".... You are going to have to think very carefully about which type of connector that you use. I would suggest that you use sockets at the boards and connect via a group of leads NOT one!

If you are carrying power then the XLR connector or the Neutrik system is superb.

Data connectors that are robust -are rare. AVOID D25 and D15 connectors as they are too fragile -use instead a SCART system -these were originally TELCO plug together couplers.

regards

ralph

Offline IanT

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Re: MERG and the "CBUS"
« Reply #19 on: March 08, 2016, 10:23:01 AM »
It's all very early days and my knowledge of CBUS is currently restricted to what I've read from the various MERG documents and their 'Forum' - so only 'theoretical' at this time.

A relatively 'simple' layout - such as MP (which is essentially pre-defined) would most likely be set up as a "SLIM' system - using pre-sets on the PCBs. If we ever need the added complexity of a fully self configuring system - then the SLIM version can be upgraded to the 'FLIM' version (full computer configure & control). It seems doubtful we will need a FLIM version in the foreseeable future though.

CBUS is a LAN system and signalling is carried over twisted pair. Obviously, the PCB 'units' that send/receive the control signals (and act on them) need more in the way of local wiring (and therefore connectors). However, signalling/switching a physically large layout will be problematic whatever system is used when that system has to be portable. There is no need for any layout to be fully automated or 'finished' on day-one - provided that we have some idea of the longer term design goals and can build in a bit of future proofing. I've always assumed that MP would evolve over time and hopefully be a good show-case for G3 best practice.

There is an active local MERG Group near to me and I do intend to contact them and seek their advice and support. I also intend to investigate CBUS (from a practical point of view) most likely by building a CBUS test rig. Once I've done this, I may be in a better position to understand the practical issues involved and to recommend the best way forward.

Regards,

IanT 
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Offline Geoff Nicholls

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Re: MERG and the "CBUS"
« Reply #20 on: March 08, 2016, 11:15:09 PM »
seems to me that if you're going to have signals, then you may as well make a feature of them and operate them as they would in real life. Have someone in each signal box operating the points and signals that would be controlled by that signal box. Then the drivers, who are actually each in control of their own loco, should watch, and obey those signals, just like the real thing.
Then the control of the signals and points is a pragmatic one, rodding or electric motors depending on which is most practicable in that part of the layout.
I suppose the above assumes some kind of operational timetable which I think is a good idea, if your just running stuff round the oval like the G1 types do, then none of it is necessary.
With regard to connectors, we've been using the 9 pin equivalent of the D25 on our club layout for years with no problem, and we have to re-erect it every week.
Geoff.

Offline IanT

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Re: MERG and the "CBUS"
« Reply #21 on: March 08, 2016, 11:45:39 PM »
That would certainly be my idea of how to run things Geoff....

Signalmen and Drivers   :-)

Regards,

IanT
Nothing's ever Easy - At least the first time around.

Offline John Candy

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Re: MERG and the "CBUS"
« Reply #22 on: March 09, 2016, 06:50:18 AM »
Quote
Have someone in each signal box operating the points and signals that would be controlled by that signal box

Absolutely .........my garden line will have at least three signalboxes and nothing will be permitted to move without a cleared signal and(where applicable) a single track token.
Probably will upset the "chase my tail" brigade without radio control but the layout complexity will require a disciplined approach or there will be some nasty pile-ups.

John.

My fellow Members, ask not what your Society can do for you, ask what you can do for your Society.

Offline John Candy

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Re: MERG and the "CBUS"
« Reply #23 on: October 05, 2016, 07:08:38 AM »
HELP REQUIRED WITH MONKTON PRIORS!

I have recently posted a similar request in another thread but have revived this older topic since there were (at that time) a number of members thinking along similar lines : Have any of you progressed the research or even implemented a CBUS type system?

Ian T is looking into the matter (as am I, since we are both MERG members) in the hope we can incorporate the CBUS into Monkton Priors but we are both hard-pressed with the layout construction and have little time to pursue esoteric concepts.

To enable us (the Monkton Priors team) to provide the best solution to point and signal control (we are not into DCC...the layout is designed for battery power)can anyone, please, offer assistance to progress our understanding of the requirements in the context of Monkton Priors.

There are systems available "off the shelf" but they don't offer the same potential benefits as CBUS and are far more expensive.

A "push button" routing system which sets points and signals for the selected route with the push of a single button is the ideal (with warnings if conflicting settings are selected or a selected route fails to set correctly).

Regards,
John.

My fellow Members, ask not what your Society can do for you, ask what you can do for your Society.