imt

Panel Boxes etc do have stand-by generators but the huge areas covered by modern control centres means there are dozens, if not hundreds of intermediate installations that are vulnerable to lightning etc. in addition to the "big house" itself. Everywhere there used to be a "box" there will be a cabin or a container full of the gubbins that enables its former business to be conducted from a hundred miles away.

 

Ever reducing staff levels "on the ground" also ensure that there is unlikely to be anyone "handy" to an incident to institute any alternative working arrangements when the worst does happen. In short, over great swathes of the network, even when a 'Plan B' is feasible, it may take some considerable time to put it into action.

 

Away from main centres you will be very fortunate if your "local" MOM is within a half hour's drive when anything kicks off. In many places, it can be easily double that. Many of them cover large territories and if he/she is at one extremity when a failure occurs at the other (Murphy's Law) there might be eighty miles to cover before they can do any good. Ditto S&T and PWay gangs.

 

The essential problem is that, the longer the chain of communication becomes, the further any away source of assistance is likely to be when a link does break.

 

John

I can see your point.  My wife was a senior manager in British Gas when it was sold to "Sid".  The prediction then was that safety and maintenance would go to the wall in favour of profits to shareholders.  Her response when I asked her about it was that of Mr Urquhart - "You may think that, you may well think that - but I couldn't possibly comment".  She and a large number of her colleagues were provided with well padded "redundancy" not long after.

To go back to the original question about what could/should be done, there is clearly a difference between protecting existing installations and what is done in good practice for new installations. I've been involved with several new MRT systems and in general the following will apply.

 

SIgnalling centres and local signalling rooms are usually fed from a system-wide power supply system. This will take power from one or two bulk substations (BSS) that convert power form the local electricity authority at high voltage into a 22kV or 24kV distribution network. Each BSS will be fed by two incoming feeds taken from different parts of the power supply network in case one network is knocked out.

 

<snip>

 

It would cost a fortune to bring the UK rail network into line with this.

Thanks very much for the detailed thoughts - which is of course what I was after.  Presumably I didn't ask the question very well - for which I apologise.

I was concerned at the post-hoc cost - however if this REALLY IS the new normal for the summer in the UK we are going to have to look at what needs doing and prioritise the requirements.

Thanks again.

I am not trying to start a polemical attack on RailTrack - this is meant to be a sensible question.

Looking at the news, once again we have a situation (full details unknown) where signalling centres and signalling has been affected by extreme weather.  Given that this is now the new normal, what can/could/should be done to prevent these problems.  We DO still get air traffic system failures - but they are rare nowadays.  In my day of safety critical systems everything had dual segregated power supplies or batteries or standby generators.

Is this a financial problem for the railways or are there practical problems that the uninitiated like me simply don't see or understand?

I wonder if they had any explanation as to why I see values much lower than yours, excepting the static load?

 

The current draw by a motor that is already thrown makes absolute sense as these are stall motors and therefore will always draw current to reach the stall position at which time they switch off.

I didn't ask them, but it may be variations in the accuracy of the equipment/method.  I am assuming you have better equipment than mine.

I bow to your greater knowledge - though why something which is in the right position needs to powered so as to move I am not clear.

I have reported my findings to DCC Concepts and asked if they are untypical.  I don't think it appropriate to print their personal reply, however they have confirmed that my findings are typical, which I summarise as follows:

Base load = 0.005 amps per unit. Which is what I found.

Switching current = 0.05 amps. For me it was 0.06 amps.

Stall current 0.12/0.13 amps for a short period.  Which is what I found.

The stall current applies whether the unit has a need to move or not. So sending a "reverse" to an already reversed point will see a 0.12/0.13 pulse.  Also what I found.

Given the crudity of my measuring device I accept that some of my slightly higher measurements are within tolerance

So now we all know.

The other reason to remove the spings is that it stops the point blades shooting over before the Cobalt switches have changed resulting in a short on the layout

I appreciate that information is good for the general reader, but in my case since I don't do frog switching (or anything else) with the Cobalts it doesn't matter to me.

It does say on the DCC site that you should remove the detent springs - and that make sense as you will be getting a snap action on the blades rather than the smooth motion of the blades which is afterall why we buy the Cobalt (or Tortoise) motors

 

 

It is however easy to spring them out if you have accidentally left them in place.

Well I use them because I have a complex control set up and they are easy to use, and only 2 wires are required (yes those mythical two wires of DCC!)

Your post probably cross with my amendment above.  It don't make a difference to my Cobalts on my layout (performance is the same spring in spring out).

Could it be higher because the springs are still in the points? i.e.it requires a bigger grunt to overcome the spring resistance?

 

Just thinking out loud.....

Yes the springs are still in. I have not had any problems with that until recently.  It needs a grunt to "push" past the centre but then the spring helps by joining in the push.  I generally don't muck about with my trackwork.

[additional]

I have just moved a set of jumpers to another Cobalt Digital IP (for those who have been reading all of this - the one which "shorted" and was repaired by DCC-C).  It is on a trap point.  Thus it is half a point AND this ones spring has been removed.  The performance is exactly the same as one with a spring - peaking at 0.13.

In summary I think that what you have is;

 

• Static load = 5mA per motor, exactly as stated by DCC Concepts
• Stall current = 130mA - about 3 times what DCC Concepts suggest
• moving current = 60, 90, 10 or 40mA which would average 50mA which is about double I see and three times what DCC Concepts suggest.

 

I am not sure on the last point of moving current though - perhaps you could confirm the moving current.

 

The challenge for your light bulb is on the stall current as it doesn't take much to light it up and if the stall current is as you suggest then that will be your issue.

I agree with that.  Understanding why it is what it is gives me a headache.  Can you spot a fallacy in the test? Do your Cobalts have a physical load when you test them?

I know of no reason why my Cobalt Digital IPs should be different to anybodyelse's.

[additional]

The movement current is a list of values I see from the moment of pressing the command button to the return to 0.01.

Causing 2 Cobalts to fire at once produces a maximum load of 0.28 for a short time.

Well - I have set up my test rig.  It is my (separate from the layout) programming/testing track with a PCP faceplate and PowerCab attached, and two pairs of crocodile clip flying leads to two point motors. NOTHING but NOTHING else is attached and the only load is 2 Cobalt Digital IP point motors. The point motors are still fixed under their baseboard and hence moving the points to which they are attached (have a physical load). Photo of rig attached.

The static load is .01 - as expected (two at .005).  The switching performance is amazing!  Sending a change direction to a single point (say from normal to reverse) results in .06 for some time during which time it moves the point mechanism, .09, .13 until stall, .04, .01 (the numbers vary a bit from time to time by the odd +/- .01).  Sending a command to reverse when already reversed results immediately in .13 again for some time (until it stalls again?) and then .01.  I would have thought if the point was in the correct alignment that wouldn't happen (i.e. commands would be ignored) - but it does this repeatably.

Now I repeat, I am reading the ammeter available on the PowerCab handset - which may not be terribly accurate.  I don't have access to a recording oscilloscope so I am writing down what I see. It's all very crude and amateur - but I think the readings are reasonably fair and correct.

I have not bothered with firing the 2 Cobalts at the same time yet.

Thoughts?

.....

Without knowing exactly what has caused the failure of the cobalt (overload welding the switch contacts together, burning out the switch contacts so they are open circuit, motor taking too long to run and overheating the series resistor or motor) it is not easy to put a finger on the exact root of the problem, but there are a few things that can be looked at:-

 

1. Low voltage on the accessory bus - The way that the CP6 works means that as the load increases the available voltage reduces, and not in a linear way, so that when the bulb starts to glow the voltage will be too low to move the cobalts reliably. When all is sorted (see rest of post!) it will be best to run the accessories directly from PowerCab and not via the CP6. In normal operation there is unlikely to be anything that will cause an overload on the accessory bus, and if it does the PowerCab will shut down and you will know what has happened and that something serious needs to be looked at.

 

2. Shorts when Electrofrog points are operated - If you are powering the frog you must cut the links from the frog to the switch rails and wire the switch rails to the stock rails. There is no way to guarantee that the switch in the cobalt will operate while the switch rails are in mid travel, especially if you have left the over-centre spring in place. Since you are powering your cobalts from the accessory bus you need to use the auxiliary switch contacts on the cobalt to power the frog from the local track feed to the stock rails and not use the defined 'Frog' connection. If you don't rewire the point at least move over to using the auxiliary switch because that will just light the appropriate lamp on the CP6 while the point is moving rather than upset the cobalts.

Thanks Suzie.  As ever very helpful. No details were given by the DCC-C engineer and I expect it's too late to ask now.

1. This is an interesting warning. At the moment - probably by accident or also maybe because there is no loco load on the track - all the points seem to throw, even in multiples.  However I 'll do as you say.

2. A good point for others reading this - I don't have any frog switching, display lights, switches or anything else attached to my Cobalts - just 2 wires from the accessories bus for power and command.

.....

I forgot to mention that my 10 or so DCC 80 Juicers were overheating in that problem time a week or so back, as there was not enough power to 'flip' the relay (didn't even know the DCC ones had relays). If we had not noticed I fear they may have burnt out eventually. Could that have happened to your point motor, the overheating due to not enough power to throw the relay I mean? 

....

I think you are probably right in some way or another, though I am not really qualified to say so.  I will be following this up with DCC Concepts when I have some clear measurements without too many extraneous other factors.

Which Cobalts are you using? I have again checked my IP Digital motors and the figures I quote earlier are still what I see (30mA changing and 45mA stall), yet you are stating that your current draw is 10 times what I am seeing 

Sorry for the delay in replying.  I have several kinds of Cobalts from 2 early analogue ones controlled through an ADFX2 board through to the latest IP ones.  I hear what you say.  DCC Concepts have been unfailingly supportive and provided useful advice as I waded in to DCC control.  I have looked at their leaflet for the IP range which says "Power: 9~23v DCC or DC. static <5mA, active average <40mA".  I am only reporting what I have seen on the digital ampere display on the NCE PowerCab handset as suggested by BromsMods above.  It has only 2 decimal places to show, but isn't 30 thousandths the same as 3 hundredths which would therefore register as .03 on the handset?  I am well known for my oblique stupidity so I could be wrong again!  So a single point throwing would raise the background load by .04, multiple ones by a varying amount over time since they all start throwing in a staggered way.  Throwing a single point I see the load go from. 0.36 amps to a peak of 0.42 amps or a throw load of 0.05 amps (50 milliamps) - which seems to be a bit higher than expected.  I may be my idiocy, the relative accuracy of the simulated ammeter or other factors introduced by this happening with the whole layout attached.  What I intend to do is set up a test rig with ONLY two Cobalts on to see what registers on the load and what changes when 1 is fired or 2 are fired simultaneously.  Then at least I shall have something exact to talk to DCC Concepts about.

Where on earth do you get this information?  The limit of the PowerCab is 2 amps.  You can monitor the current usage on the handset (SET CAB PARAMETERS - SHOW TRACK CURRENT - PRESS 1 for YES) so you can track the current draw for any accessory attached to the bus.  As far as short circuit protection is concerned I would never recommend the CP6 as this was only a stop-gap measure when it was found that the EB3/EB1 were not suitable for use with the PowerCab and, as said previously, it does not provide true protection from short circuits - use a DCC Specialties PSX1 (or preferably a PSX2 to separate loco and accessory buses, then if you have a short circuit on the accessory bus you can still operate locos, or vice versa).  The PSX range also allows a trip value suitable for protecting the Powercab to be set.

Thank you for your help.  I have checked the manual and it does indeed say 2 amps.  Sorry I should have read more carefully.  I have also switched the ammeter on (if all else fails read the operating instructions!).  I have a background at my reduced level (described in post #17) of 0.16 amps.  Changing a crossover sees the draw go up at peak to 0.42 (so much for 30 milliamps!). Causing the reset macro to run as described above (multiple Cobalts fired one after the other) I get a max reading of 0.8 amps and a beautifully lit bulb. So the explanation is clear.  

Adding most of the rest of the load, including my 2 NCE Mini-panels gets me up to a background 0.34 amps.  Strangely the peak firing loads are 0.54 for a crossover but the maximum of 0.8 for the macro doesn't seem to change(??).

Sadly I cannot afford the PSX range.  I have 4 separate busses and the cost is eyewatering.

Any advice at affordable levels would be very gratefully received - with apologies for wasting so many people's time.

10*Cobalts @ 30mA= 300mA, 10*LEDs @ 20mA = 200mA which is a total of 500mA or 1/2 Amp, which will get your bulb glowing nicely, your standing load is 250mA which is on the bottom end of lamp being obviously lit and in a dark corner you might see it, but add in a Cobalt or two and I would expect to see you see it starting to light clearly. (We used to use lamps dim when paralleling generator phases as it is remarkably easy to see when a lamp is just starting to light up therefore out of phase (and it doesn't take much current))

 

The numbers all add up, and if you are running several locos at the same time you are getting close to the 1 amp capacity of the Powercab, as you need also to consider the standing load of the locos when they are on the track, especially when they have LEDs - not a lot for each one, but it soon adds up, especially in larger gauges e.g. 00/h0 where the current draw is higher.

 

BTW - True RMS meters can be bought for £15 now

Thank you for bearing with me!  I obviously failed to move decimal points appropriately or to add the results properly.  Ugh!  Sorry.

I now see what you are saying.  Is this situation OK - can I continue like this - or do I need to revise my whole layout powering ideas?  If so how - cost IS a problem. |What do I do with my CP6? Careful this is a family show!

My age is showing! RMS meters for £15!!!!!  Strewth at that rate worth waiting for even if it does have to be shipped from China.

Thanks again!

Iain. You are not alone. Just last week something similar was being discussed about my layout. I was advised to go back to the Panel out put (NCE as yours) and work from there, testing power at track head after every adjustment/link up. I was also advised to comb the layout for shorts despite the fact it wasn't a short that was causing the problem as far as a friend  and I could see. Once, long before this, I had found that I had wired up something strangely which was sort of contra feeding between BUSES and that was causing problems; I have no idea how I cured that but I did! Another time I found a rogue track pin causing a problem and on another time a loco that was faulty that drew loads of volts.

I really think the going back to the start of the accessory power supply and working outwards might help? Could there be some sort of contra flow between the point motors and the BUSes?

Oh yes, I did find a point that I had not used an IRJ on at the heel (of one of the stock rails). I was advised long ago by a very wise and experienced modeller, to use IRJs every where and power every section of track (droppers). That has worked for me in the main but I have cheated on some long straight sections and relied on rail joiners (but with unattached droppers ready just in case) .

If you want to try a power supply with a bit more oomph, I have the NCE 13.8V @ 1.8A if you would like to borrow it?

Phil

Thank you for all of that.  I have had similar troubles myself when trying to sort out power districts.  Sadly we only learn (mainly from our own) mistakes.  I think the insulating rail joiners advice would have been good for me too.  However that does not apply in this particular case, since the accessory bus is separate from the track buses.  Thanks for the offer of a loan of a heavier duty power supply, but I don't think that is my problem.  I'll keep in touch on that.

It suggests to me that you are towards the limit of available powerr on your accessory bus, and potentially towards the top end on your available power from the Powercab. The power availability of your accessory bus is being limited by the bulb, as suggested by Nigel, and if the movement of a cobalt motor at between 20-30mA change current, is sufficient to cause the bulb to glow then you are at the limit and need to consider the items being used on it - or accept that the bulb glows (glowing is a somewhat relative term though, you could be anywhere on a large range of current draw). I would be tempted to put an ammeter in the circuit to find what the actual total current draw is, and also measure the individual busses and items to see where the excessive draw is.

 

The other option is to get a commend system that can deliver the current capacity that you are using.

Thank you for your thoughts.  I accept your theory - but I don't see it borne out in practice.

Just for the hell of it I have disconnected the other three power districts AFTER the CP6.  I have checked that there is no power on ANY part of the track.  I have disconnected my controlling NCE Mini-panels.  I have disconnected the corner and fiddle yard boards from the station & port boards - physically and unplugged their cabling.  I have disconnected the bridge rectifier and the IRDOT from the accessory bus "just in case" (easy to do by removing one wire).  The only items connected to the PowerCab are on the only bus left connected - placing a loco on the track has no response because there is no power.  The final accessory bus has 10 Cobalts and 10 signals ONLY (the missing small number are on the disconnected boards (3 Cobalts and one signal).

Sadly sending commands to this tiny load results in the bulb glowing.  If I deliberately send some commands to set the main points to reverse and then use the reset macro which will sequentially (but without pause) sends "set normal" commands to the Cobalts then the bulb glows brightly for several seconds as the motors whirr. The interesting thing (to me) is that ALL the points are returned to normal, none get missed.  The "overload" does not confuse or lose the DCC commands.

Sadly I don't have an RMS meter suitable for checking things (nor the budget to buy such an expensive thing) and I doubt if my best Maplins analogue unit will get anything worth reporting.  The standard load is 10 micro LEDs and their controllers and 10 * 5mA for the Cobalts.  Even if I fired all 10 Cobalts simultaneously then the draw should be 10 * 30mA  which (as you say) should be insignificant. I doubt if the whole shooting match exceeds .05A let alone the .5A which should be necessary to set the bulb off.

I understand what both Nigel and you have said - but I don't see how it applies.

i have just looked up the stall current of the Cobalt Digital IP Motor which DCC Concepts state is 20mA stall at 12v and 16mA when changing. This means you would need to have 50 stalling at the same time to draw the 1 amp your bulb needs to light up, or 62 all changing at the same time. The static load is <5mA per motor which means 200+ to draw 1 amp - that is an awful lot of point motors

 

Now I don't know how many motors you have but as you are running the layout on a NCE Powercab I feel it may not be that many, which would suggest that blaming the Cobalt motors may be a mistake and that the fault lies elsewhere?

 

For comparison my static load is 420mA and this is caused by 25 Digital IP Motors and 8 locos with one loco drawing almost 150mA because it has incandescent bulbs (they are changing to LED at the weekend).

Thank you very much for continuing to help. As Nigel Cliffe has pointed out - though I have 4 separate "power districts" the total power supplied by the PowerCab is 1 amp - so exceeding that on all 4 legs will trip the Power Cab itself.  This DOES NOT HAPPEN.

As I have said all accessories are on a separate feed which is not connected to any track at all.  I would assume therefore that (though the overall load may affect the PowerCab) what is on the layout does NOT affect the accessories bus.

The accessories bus feeds round the whole layout - about 18 feet max. I would think.  There are 5 TrainTronic signals, 6 GPLS, 13 Cobalts (maybe thats the problem! perhaps I should buy another?) and a bridge rectifier feeding a minor DC current to an IR detector. That's it.

As I have said, I have a control system which can issue multiple DCC commands to the bus and when that happens the sounds of moving Cobalts are accompanied by the glowing of the appropriate CP6 light.  I can get the same effect if I disconnect (and so discount the conrol box) and use the PowerCab handset.  Single commands can set a point or in some cases a crossover (2 points), I have a PowerCab macro which resets all main points to "normal" - which at the ultimate can fire off 10 Cobalts if they were all in the wrong setting (most unlikely).  The glowing of the CP6 light appears to be proportional to the number of Cobalts that move position. This can be over quite a long period as commands go out from the handset serially but the Cobalts may take a second to fully throw, so there may be several moving at once.

Does that help or confuse the issue further?

The "light bulb" protection method is not a protection against short circuits, instead it limits the maximum current flowing through the bulb, and in turn, limits the maximum power drawn from the command station.   At low currents, the resistance of the bulb is low and it stays dark.  As the current rises, the bulb's resistance increases, the filament glows and light/heat comes from the bulb.  

 

So, what you appear to be seeing is a current draw of above 0.5A, and possibly approaching 1A  (the usual limit of the NCE bulbs).    As the bulbs are rated at about 1A each, then a Powercab will still be overloaded if three light, and possibly overloaded with two lit. 

 

 

An additional factor with "Cobalts" is "which model of Cobalt, and how is it wired ?"    If you are using the Cobalts which come with the integral frog switch, and you are using that frog switch output, then your frogs are powered from the Accessory bus.   That has consequences should there ever be short circuits at the frogs as power is coming in along track bus and out via accessory bus (or visa-versa).   The solution to this is to not use the "rather too clever for its own good" frog output, but instead switch a frog using the other accessory switch with two wires in from the track bus and one out to the frog. 

 

And finally, what track, and how is that setup ?   Again, I've seen people use unmodified N electrofrog turnouts (think the same is possible in other scales), then connect a wire to the frog, and wonder why there are shorts when the turnout motor is operated. (because the switch on the turnout motor and the switch at the point blades move at different times, so there IS a short until both have moved enough.). 

Thank you for your thoughtful reply.  I think I understand the bit about how the bulb function.  The Cobalts are a mix of old and new: old controlled by ADFX the new ones with built in electronics.  The track is Peco: mix of fixed length Setrack and flexi, the points are Streamline - all code 100.  Most are electrofrog, I have not messed about with them to "DCC" them or done any frog polarity switching.  The Cobalts are simply fed with two wires from a separate bus, no extra wiring, no use of "clever" switches.  So I still don't understand the huge power demand on the accessory bus - presumably by the Cobalts.  Any help/advice/explanation on that greatfully received.

I know this sounds odd but maybe you actually do not have enough power going into your BUSes? 

I hear what you say.  I MIGHT believe that if anything else (i.e. locos) were drawing power.  They are on the track, but nothing moving.  

I got rid of the 'glowing bulb' protection method and replaced them with NCE EB1 power breakers which are much more effective.

Quote from their NCE EB1 web page "This is not recommended for use with the Power Cab. For the Power Cab use the CP6. ".  So I did that!

Please excuse me I have been overwhelmed by my ignorance and would appreciate some guidance from more knowledgeable/better qualified persons than myself.

Background: My layout is a small BLT with 4 road fiddle yard.  I have a NCE power Cab with an NCE ProCab as a slave.  I have a "control box" (as you do) with buttons to set routes and multi-colour LEDs to show how signals are set.  The output is through NCE Mini-panels onto the NCE bus (via a standard NCE face-plate) - so nothing I have done should affect that output, which will be a string of accessory commands in DCC format on the NCE PowerCab supplied power.  I have been running thus for some time with no (apparent) problems.  For wiring convenience I had split the power out from the NCE face-plate into 4 feeds (Power Districts) 1 for the main station, one for the complex Quayside that I have, one for the fiddle yard and one for all the accessories.  So all accessories are powered and DCC commanded from one bus.

Failed DCC-Cobalt: One of my Cobalt point motors failed.  I took it out and returned it.  They kindly fixed it and returned it saying that the electronics had been damaged by a short circuit.

Insertion of NCE CP6 (car lights?): I felt uneasy, so before I put the Cobalt back I bought an "NCE CP6 Circuit Protector" specified for the PowerCab and wired that in after the faceplate.  The the CP6 also splits the output into 6 - I needed 4.  I have tested the 3 supplies to trackwork and they work fine - short on one circuit does not affect another and the bulb lights.

PROBLEM:  Light on PD4 - the accessories bus - glows at varying brightness whenever a string of commands is sent out by the Mini-panel (a route might be several points and a signal say). Horror! Aghast I tried using just the NCE PowerCab handset to send single commands to an address - some are single points, some are crossovers with 2 points on the same address, some are signals (TrainTech DCC or CRS with TrainTech DCC controllers). Signals change without the bulb glowing, single points change with a small glow, crossovers cause a brighter (but still small) glow. Aaaaaaaaaaaaaargh!  What am I doing???  It seems to be just the Cobalts and the more the brighter (if you see what I mean!).

Question: Am I over-reacting?  Is this actually OK?  Should Cobalt point motors somehow short ciruit the supply - HELP PLEASE.

EDIT:  I just realised of course that it is not a "short" necessarily but maybe an over demand on the supply?

Whoa!  Take a step back.  A sector plate is a piece (a section of) a circle.  All I see is straight lines. You will need to curve something they cannot be (as they look, though I may be mistaken) straight tracks.  You cannot curve a Y point (well you can and I have but I don't recommend it).  You will need to curve the other plain track.  I suggest you put the centre of the sector plate square with the Y point - which it isn't at the moment - and curve the plain line into the sector plate.  I would suggest your sector plate needs a curve on its face? Else how does it turn?

I agree with Zomboid - the more you have to do to set up, the less likely you are to do it.  Cassettes do take some building BUT when done provide a ready storage system and can turn whole trains round (relatively!) easily.  You can also have loco sized cassettes which enable you to swap ends/directions too.  The aluminium section and bulldog clips is probably the easiest way.  You do need some shielding on the sides if you want to move them away from the FY so things don't drop off (Or very large aluminium angle).  I have seen heavy cardboard stuck on the sides for this purpose.  The cassettes need to be simple and easily manoeuvrable.

Now I get that you need to be able to remove the FY.  An alternative is a fold-able table which can rest against the fixed (most out of the way) part of the layout when not needed and which can have cassettes put on it to connect to the feed.  As I say I suggest 2 feeds using a curved point.  This will give you cassettes of the full 1480mm long - which is loco plus 4 coaches and will fit your station.  You NEED you fiddle yard to be a good fit for what your traffic will be. 2 feeds would let you have an empty cassette for outgoing traffic plus a full one for incoming (say) saving mucking about with point changes on a ladder or having to change a single cassette.  By the way - if you end the feeds on the fixed board so the cassettes can align with them then you don't need to cut and solder rail!

The cassettes can be stored on shelves above the layout - much easier than moving individual carriages/wagons somewhere when you need to remove the "obstruction". You can keep whole rakes together this way ready for use next time.  Set up for a new session can be quite quick in my experience..

Keep thinking outside the box and it will help you get something that works well in your situation.  It is a good space for a nice working layout.  Stick with it!

Having my own problematic restricted area I know your difficulties.  Three things to think about:

1. why the two kickbacks in the FY? Presumably for locos. Why not use a Peco LocoLift or two - saved me a lot of space and allowed longer trains.  You could also have another 20 cm and still be clear of the door swing.

2. why not (since you will have one line across the joint) go the whole hog and start the split for the FY using a curved point behind your goods shed (?).  Once you are into soldering track across joints you get used to it - by the time I got to my 24th joint (mine has to strike completely) I was quite good at it!

3. It would (I think) be easier and give more flexible use of space if you used cassettes.  The fan of points wastes space and of itself can cause problems with stock doing "S" bends over them - they derail more easily.

The reason you are being warned off is alignment problems.  You need to ensure proper alignment when you fold it down again.  Difficult to use dowels in this case.  Removable would be easier in that you could use dowels and case latches  which would make it steady and readily aligned. I think this is a room in a house so maybe no problems with expansion/contraction/water?

(added)

What I have seen for alignment of lifting sections is the use of metal (aluminium).  I am looking for photos which I know are somewhere!  The strip was on the fold down section (so it didn't stick out in the way when lifted) and went into the stationary board through a slot which was reinforced by metal angle on the other side.  Absolutely rigid in its effect.