Dapol working signals review

[Andy1963]

I would have though a point decoder would work.

[9h1bw]

That is what I was thinking. However in a review I read else where it says that the yellow wires require a push to make switch, and that if I understood correctly one click causes the arm to go in one direction and another click moves the arm i the opposite direction. If a point decoder, with CDU I presume, is used it would give a burst of voltage and not a switch, or short of the yellow wires. Has anyone seen any installation instructions?

[Andy Y]

Does anybody have an idea what type of DCC decoder will be required to operate it?

That is what I was thinking. However in a review I read else where it says that the yellow wires require a push to make switch, and that if I understood correctly one click causes the arm to go in one direction and another click moves the arm i the opposite direction. If a point decoder, with CDU I presume, is used it would give a burst of voltage and not a switch, or short of the yellow wires. Has anyone seen any installation instructions?

 

Please see http://www.rmweb.co.uk/community/index.php?/topic/53096-Dapol-working-signals-review/page__view__findpost__p__630506

[Edwin_m]

I don't think that link fully answers the question. There seem to be three issues to think about here:

 

- We are told that two wires from the signal are connected together to operate it. As noted down the link a relay (or solid-state equivalent) is needed to connect these together when energised from the decoder output. However we need to know the voltage and current that flows between these two wires and whether DC or AC, in order to define the relay type (maybe even to choose a suitable push button, if large currents are involved!), and with access to the actual circuit people might find simpler ways of doing things. I hope either Dapol publish some technical details or someone posts the results of experimenting!

 

- It also seems that the signal is "toggled" each time these two wires are connected to each other, whereas most accessory decoders produce a pulse on one output when set one way then on the other output when set back the other way. I think Kato points work this way too, so whatever solution is used for those may be suitable.

 

- For DCC users and indeed non-DCC users who want to work the signal by a simulated lever, there is the problem of the signal getting out of sync with where the "control system" (lever position, DCC accessory state, computer memory) thinks it is. For example if the control system assumes all signals are "on" when the layout is powered up, then any that are left "off" will be in the wrong state right through the operating session. Moving the signal arm by hand may cure this depending on the mechanism, but even if it does it is hardly an ideal solution!

 

Many years ago I dismantled a non-working Hornby-Dublo signal which appeared to be "toggled" in the same way. It had only one solenoid coil with an ingeneous mechanism with a sort of rocking cam linked to the arm. The solenoid worked a sheet of bendy phosphor bronze, which dropped into one of two slots in the cam in such a way that each successive "pull" reversed the cam's position. Does the Dapol signal do something similar?

[Pennine MC]

How many of all the others would have to sell before we got somersault signals?

 

Somersaults would be nice, but they're not gonna turn the world upside down.

 

 

 

[Jenny Emily]

Having finished my last Ratio signal kit last night, I now understand what modellers mean when they say "start the kit, and the RTR version will come". These signals looks extremely impressive. As a child I had a Hornby Dublo layout and loved the electric signals. They've been sadly missed in my opinion from the hobby since Meccano's demise, and these Dapol versions finally look like more than worthy successors. Given what you get for the price, I'd say that they are pretty reasonable.

 

I only ever managed to mechanise maybe a quarter of the Ratio kits I built, so to be able to get reliable and robust out of the box ones is great. I'm almost tempted to start the process of slowly uprooting Ratio signals and replacing them with Dapol ones as money permits. However for now the more complex gantries and junction signals will most likely stay. I do look forward to seeing what more complex signals appear in the range.

[The Stationmaster]

I do look forward to seeing what more complex signals appear in the range.

The major problem with 'more complex signals' is exactly what does the manufacturer chose? Ratio did it quite well with their first range of GW timber post signals but it was a fairly limited range with two splitting signals (one left and one right) plus an offset bracket and that, I think, is where a line will tend to be drawn because beyond that - with the possible exception of a balanced bracket separated to serve two lines - things start to get quite bespoke. However a 'plug-in' modular gantry would be a great idea - but not easy to achieve I suspect.

[Elvinley]

Looks great. How come the distant has a red spectacle glass instead of yellow?

Edited March 11, 2012 by Elvinley

[iL Dottore]

I'm looking forward to the 4mm versions (I'm going have to dig out my layout plans to see how many of each I will need to purchase). The base footprint for the 2mm version is 30mm x 20mm so I wonder what the base footprint will be for the 4mm versions? I'm thinking of deviating from the mounting instructions and instead of cutting a 14mm hole for the threaded base, cut a N mm x N mm hole so that I can mount the signal flush with the baseboard, to give a more prototypical aspect.

 

Jenny Emily wrote about both complex and gantry signals, which I do need, so I'm wondering how easy it would be to cannibalise/modify these signals to create a more complex signal and whether or not the internal "gubbins" are sealed?

 

Well done Dapol.

 

F

[chrislhurley]

I have been watching this and other forums over the last few days whilst we DCC users try get to grips with the new Dapol signals. Perhaps a bit more by luck than judgement I have found a working solution.

 

I am an ECoS/RR&Co user and this what I have done. Create a toggle signal for the switchpilot (I assume that this will apply to most if not all accessory decoders). Using a dpdt-no relay I have connected the decoder common to one input pole and BOTH decoder A and B to the other input pole. This enables the decoder to show green or red (go or stop) on its graphic (and on RR&Co). I then connected the two yellow wires from the Dapol signal to the relay's centre pole and "normally open" pole. (Make sure it is not connected to the "normally closed" pole!!)

 

The affect of throwing the signal on the decoder is to close the relay which then returns to "normally open" achieving the push to make operation as recommended by Dapol. I am using dpdt simply because I had it in my bits and pieces box but I guess spdt-no would work just as easily.

 

I then set the unit up on RR&Co and watched the signal behave as per screen action - train comes to a halt, signal drops, train leaves then signal restores to stop - a delight! Another "well done Dapol" from me!

 

The only uncertainty is whether it is possible after shutdown and restart the signal position remains unchanged. I am not hopeful but will report on outcome when tested.

 

I am not a major poster but an avid reader of RMweb - I hope this helps!

 

PS - I understand that Dapol have spotted the distance signal jewel being the wrong colour and are "sorting it out" - not sure what that means yet.

 

Chris

Edited March 21, 2012 by chrislhurley

[N Gauge David]

I hope this helps!

 

 

 

 

Hi Chris

That's a very helpful post, as I am also running ECoS and RR&Co, and was wondering how the Dapol signals would work. I am waiting for the LMS upper quadrant versions (not long now...).

 

I am not familiar with relays, so was wondering if you could describe what you mean by DPDT-no or SPDT-no relays? Also how do you identify the "normally open" pole on the relay? If you could give me a heads up on the above, as well as a link to where you can buy them, I'd be grateful.

 

Thanks

David

[chrislhurley]

Hi Richard

To be honest I am not entirely knowledgeable in the area of relays either – I just happened to have one that worked in my spares box! Anyway I googled the code and come up with this:

http://datasheetz.com/data/Relays/Power,%20Over%202%20Amps%20@%2030%20VDC/OMI-SS-212D,500-datasheetz.html

 

This helped me understand how it worked. One set of terminals had a permanent connection when it “rested†and one set didn’t – which is why you can see I chose the particular pole in question. This gave me the pulse I needed. Then it was all down to finding someone who sold them – not that difficult if you put the relay code into google and add ebay!

 

I think that others with better knowledge will find a simpler relay (ie spdt) but as it met my needs…..

 

There is a downside – when the ECoS restarts the signal doesn’t retain its memory, like the points, which I guess is not surprising as it is a simple pulse. However initial impressions are that RR&Co does correctly reset. This is based on early tests but I haven’t done enough to be certain yet.

 

Chris

[Etched Pixels]

For lower quadrant and DCC you may want to look at the Tomix signal instead. That is DCC controllable and looks very UKish. The one with the distant as well lacks the 'V' cutout so only matches very early practice but I'm sure could be 'edited'

 

Another option might be to use a tortoise style controller that produces a 5v or so output and can be set to pulse, that'll drive an SSR (solid state relay) rather than a mechanical one. You can pick them up for £3 or so and with no moving parts they draw almost no control current and don't wear in the same way. They are polarised and deeply offended by excessive reverse current so need to be wired the right way round though.

[beast66606]

For lower quadrant and DCC you may want to look at the Tomix signal instead. That is DCC controllable and looks very UKish. The one with the distant as well lacks the 'V' cutout so only matches very early practice but I'm sure could be 'edited'

 

Early practice was to have the V but the arms were the same colours as stop arms. This changed from 1922.

[whiteswan]

The affect of throwing the signal on the decoder is to close the relay which then returns to "normally open" achieving the push to make operation as recommended by Dapol. I am using dpdt simply because I had it in my bits and pieces box but I guess spdt-no would work just as easily.

Chris

 

,

 

 

Chris,

 

I think I've found a single pole normally open relay on Rapid Electronics web site http://www.rapidonli...ure-relay-74442 , looks as though this will do the job.

 

Caz

 

(Also replied to Chris on the Yahoo N Gauge group but thought I post this link here as it may be useful to others)

Edited March 22, 2012 by whiteswan

[stewartingram]

Hi Chris

That's a very helpful post, as I am also running ECoS and RR&Co, and was wondering how the Dapol signals would work. I am waiting for the LMS upper quadrant versions (not long now...).

 

I am not familiar with relays, so was wondering if you could describe what you mean by DPDT-no or SPDT-no relays? Also how do you identify the "normally open" pole on the relay? If you could give me a heads up on the above, as well as a link to where you can buy them, I'd be grateful.

 

Thanks

David

 

Simple explanation about relays and switch definitions, maybe this will help?

 

A relay is only a remote controlled switch; Basically you operate 1 switch, which passes current to the relay COIL; by magnetic & mechanical operation the coil then moves the CONTACTS mounted on the relay. These CONTACTS actually function just as a switch would, hence the REMOTE SWITCH analogy.

Relays come in many shapes, sizes, and spec as to operating voltage to work the coil, but don't get too worried about that for now.

Switches also come in many shapes, such as Toggle, Push, Rotary, Slide, Microswitch etc but all contacts operate in a similar way.

 

SWITCH CONTACTS, which are essentially the same thing as RELAY CONTACTS, can have 3 basic functions.

1) MAKE contact, otherwise known as NORMALLY OPEN. An example of this is a torchlight switch; nothing works until you turn it ON.

2) BREAK contact, otherwise known as NORMALLY CLOSED. Works the opposite way round to the MAKE CONTACT version.

3) PASSING contact, which starts as NORMALLY OPEN; as the switch is operated it goes through a MAKE operation, but the another BREAK operation after that. In other works, it cannot be left ON; a simple example would be the old Triang/Hornby point motor lever switches.

 

Note that a CHANGEOVER contact combines 1) & 2).

 

If the switch lever has only 1 movement, ie moves from one position to only one other, it is known as SINGLE THROW.

A lever with 2 movements is DOUBLE THROW. Example: a Centre OFF position, with an ON position in either LEFT or RIGHT.

 

All the above refers only to 1 POLE. ie a 1-wire circuit if you like. If you have 2 poles, in effect you have 2 separate switches (electrically) but actually coupled together mechanically. So you move 1 lever, but move 2 separate sets of contacts, which may be either of the same type, or different. A switch can actually have a number of poles, in practice anything over 4 pole is unusual.

 

For each type of description, a simple code is often used.

 

DPDT- NO is short for:DOUBLE POLE, DOUBLE THROW, NORMALLY OPEN.

SPST - CO is SINGLE POLE, SINGLE THROW, CHANGEOVER

DPST- NC is DOUBLE POLE, SINGLE THROW, NORMALLY CLOSED.

 

Many other permutations are possible, but should now be easy to work out. Don't forget - relay contacts are only switches so follow the same rules.

 

Hope this helps?

 

Stewart

Edited March 22, 2012 by stewartingram

[N Gauge David]

 

For each type of description, a simple code is often used.

 

DPDT- NO is short for:DOUBLE POLE, DOUBLE THROW, NORMALLY OPEN.

SPST - CO is SINGLE POLE, SINGLE THROW, CHANGEOVER

DPST- NC is DOUBLE POLE, SINGLE THROW, NORMALLY CLOSED.

 

Hope this helps?

 

Stewart

 

Certainly does, Stewart. Thanks for that.

ATB

David

[Budgie]

Surely a changeover switch is by definition double throw, because it changes over from one on position to another?

 

I don't understand DPDT - NO, as all the double pole double throw (also described as double pole changeover) switches I've got are closed one way or the other when in their thrown position. The only thing that distinguishes DPDT switches from each other is whether they are make before break or break before make. In the first of those both ways are on when changing (so they are no good for reversing switches as they will give a short circuit) and in the other neither is on when changing.

 

As I understand it, normally open and normally closed only apply to sprung switches (such as microswitches). The spring ensures that one set of contacts is normally open or normally closed unless the switch has been operated against the spring.

[Stubby47]

Would a DPDT-NO be sprung to a centre off position, so pushing either way would only momentarily make contact ?

[stewartingram]

Surely a changeover switch is by definition double throw, because it changes over from one on position to another?

 

I don't understand DPDT - NO, as all the double pole double throw (also described as double pole changeover) switches I've got are closed one way or the other when in their thrown position. The only thing that distinguishes DPDT switches from each other is whether they are make before break or break before make. In the first of those both ways are on when changing (so they are no good for reversing switches as they will give a short circuit) and in the other neither is on when changing.

 

As I understand it, normally open and normally closed only apply to sprung switches (such as microswitches). The spring ensures that one set of contacts is normally open or normally closed unless the switch has been operated against the spring.

 

A ST switch only has one lever movement. If it has a centre-off position it becomes a DT because there are 2 movements to complete the throw. It can be a simple ST CO or a DT CO centre-off.

 

In the interests of keeping it as simple as I could, I deliberately omitted make-before-break etc so as not to complicate it.

 

I agree that most common switches have sprung contacts; however consider a slide switch or a rotary switch. These can perform exactly the same electrical switching, but the contacts are not sprung over to a rest position. This is determined by the position of the operating knob or whatever. So an electrical definition of the switch contact actually remains the same.

 

Good point about the DPDT - NO though, I confess to having just "plugged in" the relevant code to the original description! Hovever, it is technically possible to build one, just think of a 3 position rotary with NO contact on position 1 & 3, with NC only on position 2. Though why you would...?

 

As I said there are many styles of switch. Even a simple toggle, with a centre off position (ie a DT switch) can be complicated by having a sprung loaded lever, so you cannot park it in one or other (or both) ends of the throws.

 

 

Stewart

[Budgie]

A ST switch only has one lever movement.

Your normal light switches in your house are single pole, single throw. Obviously, they have two lever movements, one to switch the light on, and the other to switch the light off.

 

If it has a centre-off position it becomes a DT because there are 2 movements to complete the throw. It can be a simple ST CO or a DT CO centre-off.

 

If some of your lights at home can be operated by two different switches, these are single pole double throw switches. Again these switches have two lever movements. Note that they do not have a centre-off position.

 

What do you mean by ST CO? (Single throw centre off, maybe? Never heard of it! Single-throw change-over? Impossible, since change-over is a synonym for double throw).

 

In the interests of keeping it as simple as I could, I deliberately omitted make-before-break etc so as not to complicate it.

 

I agree that most common switches have sprung contacts; however consider a slide switch or a rotary switch. These can perform exactly the same electrical switching, but the contacts are not sprung over to a rest position. This is determined by the position of the operating knob or whatever. So an electrical definition of the switch contact actually remains the same.

 

Good point about the DPDT - NO though, I confess to having just "plugged in" the relevant code to the original description! Hovever, it is technically possible to build one, just think of a 3 position rotary with NO contact on position 1 & 3, with NC only on position 2. Though why you would...?

 

As I said there are many styles of switch. Even a simple toggle, with a centre off position (ie a DT switch) can be complicated by having a sprung loaded lever, so you cannot park it in one or other (or both) ends of the throws.

 

 

Stewart

 

People might find the Wikipedia article on Switches helpful.

[Ruffnut Thorston]

Can anyone say why the signal power supply has to be AC?

 

Can not a 12V DC supply be used?

 

(Solar Powered Battery Operated Model Railway.)

[Captain Kernow]

Are there any photos around of the 4mm versions of these signals - all the photos are of the 2mm ones so far, aren't they?

[Andy Y]

I never thought to get some quick snaps yesterday Tim but maybe Dave can drop me a couple when he gets back from AP; I can confirm the distant does have a yellow spectacle too.

[The Stationmaster]

Are there any photos around of the 4mm versions of these signals - all the photos are of the 2mm ones so far, aren't they?

 

The 4mm ones don't look too bad from what I could see in Dave Jones showcase (you thought I was going to say something else) yesterday. From a view, and not a measurement the UQ steel post signals look good although I wonder a bit about either the arm proportions or the position of the white band on the stop signal arm.

 

The GW square post distant again has the odd shape of the black 'fishtail' seen on illustrations of the 2mm signal and the arms (as on the UQ signals) look a little 'heavy' but that is almost certainly a result of their being plastic mouldings with durability in use being a strong consideration (strikes me as far better than them falling apart after being pulled-off a few times ). A bit less easy to understand are three horizontal 'bands' in relief which appear to go around the post - the ladder stay goes to one but I'm not exactly sure what the other two are meant to be although i suspect they might be an 'interpretation' of the downrod guides - probably readily removed with a scalpel if their presence offends?

 

Overall the proportions of all the signals was quite pleasing and I reckon they are a great step forward for the hobby.