Lighting control panel

[gavino200]

I'm planning my first non rolling stock lighting project. I'm adding lights to my Kato station. My layout is urban and I plan on adding a lot of lights in future, so I'd like to design a control panel that is neat and expandable.

 

Our train room doubles as a den/reading room so I wan to keep it looking ok without too many ugly wires and switches. Below is our control center so far. The circuits are fixed to a board that sits in a piece of furniture. All the wires are detachable at the back so the circuits can be easily slid out.

 

I'd like to use the space on the left for the lighting panel. Future panels (signalling, junctions etc) can go on top or somewhere else.

 

 

 

This is the board that I'd like to build the control panel on.

 

 

So far as is see it, this is how it would work. On the back of the board I'd fix some (one now, more later) of those 12V transformer to wire connectors that JR 500 uses. I'll add a link when I can find one. That way I'd have neat detachable power imput at the back. There would be wire slack in the back so that the panel can be easily pulled out about 12 inches for use.

 

The board would then be divided into zones. For example the whole Kato station and carpark would be one zone. A city block could be another zone. And so on.

 

I could have a single switch at the entrance to each zone. That way the zone could be truned on or off as a block.

 

The the zone wire could then be split at a junction box into a number of subcircuits - each controlling a particular element. An element could be a particular platform, or the station house, or part of the station house, etc. I'm planning to use a small breadboard for each zone as suggested by Jeff.

 

Each element sub-circuit would have it's own switch, a potientionmeter, a small LED indicator and a label. All the sub-circuit wires could lead to a ribbon connector at the back of the board, so that the board could be easily disconnected from the wiring to the layout. From the ribbon the wires would go to the layout. I would probably use a pair of colored scheme for each zone for easier trouble shooting. I'd appreciate if anyone knows of a good ribbon type detachable connector for 30 gauge wire.

 

This way I could have as little or as much control of the lighting as I want. I could have it so that just turning on the power strip turns everything on. Or I could control zone by zone, or building by building.

 

The reason for all this control is that it would probably be fun when playing cops'n'robbers and other games on the layout.

 

 

Anyone see any obvious problems with this? Or have any suggestions?

 

Anyone know of any small but reliable switches I could use?

 

 

As always I appreciate your help and ideas :)

Edited April 5, 2017 by gavino200

[gavino200]

Here's a picture of how I imagine the panel with one zone filled out.

 

[gavino200]

Most of this stuff is sourced/bought. I'm using the transformer to wire connector suggested by JR 500. Potentiometers and cheap breadboards suggested by Jeff along with his circuit design including the 100Ohm resister. 

 

I'll choose switches and LEDs that seem durable and look good. Not sure what switches yet.

 

My main question regarding this design is about the detachable wire connector. I'm thinking about something that can plug in and out in much the same way as a molex plug. However I'm looking for something that will work with 30 gauge wire (4-10 pairs of wires per zone). 

 

This connector will be the main bottleneck on the panel. What would be great would be to use detachable connectors that could be stacked on top of each other vertically. That way all the exit wires would route to one hub avoiding a mess at the edge of the panel.

 

Other than a vague notion of having seen things like this in computers and other electronics (neither of which have I expertise in) I don't really have a specific connector in mind. I'll rummage through McMaster and other electronics supply sites. However, if any of y'all know of a connector that might fit these criteria I'd be extremely grateful.

 

The other main question is whether anyone knows of a better way of designing this. I have a lot of components to collect and buy and a fair bit of planning still to do, so I have time for as many complete redesigns as it takes. 

 

Anyone think of a way of doing this that is more functional, more miniature, computerized, or just better looking even, I'd love to hear your suggestions. Computer, arduino, scratchbuilding, whatever. Please share.

[Kiha66]

For my own project I was using 40 pin ribbon cable running to breakout boards I salvaged off an old retired industrial control system.  Depending on how many wires you need and the length you plan on moving the board, a D-sub or RS232 type cable could be easy to plug and unplug.  A suggestion might be to use a common ground for all the lights, as this would cut down on half the wires you need to run to the board.

 

Some examples:

25 pin DB25 cable

25 pin DB25 Breakout board

[gavino200]

For my own project I was using 40 pin ribbon cable running to breakout boards I salvaged off an old retired industrial control system.  Depending on how many wires you need and the length you plan on moving the board, a D-sub or RS232 type cable could be easy to plug and unplug.  A suggestion might be to use a common ground for all the lights, as this would cut down on half the wires you need to run to the board.

 

Some examples:

25 pin DB25 cable

25 pin DB25 Breakout board

 

Thanks Kiha! Those look perfect. I'll do some research on common ground but I think I understand it. 

 

One positive wire would go through the main zone switch and then get split into sectors wires that would each have the resister, sub-switch, pot, and indicator LED. From there they'd go to the layout. 

 

The other wire - the ground - would go directly from the 12V transformer to the layout without being split. It could run as a kind of "bus" beneath all the structures in the zone. Feeder wires could go then from the common ground to the individual LED sectors to complete the each circuit. 

[Kiha66]

Thanks Kiha! Those look perfect. I'll do some research on common ground but I think I understand it. 

 

One positive wire would go through the main zone switch and then get split into sectors wires that would each have the resister, sub-switch, pot, and indicator LED. From there they'd go to the layout. 

 

The other wire - the ground - would go directly from the 12V transformer to the layout without being split. It could run as a kind of "bus" beneath all the structures in the zone. Feeder wires could go then from the common ground to the individual LED sectors to complete the each circuit. 

Yep, so the power would go from +12V on power supply through pin one on the wire to the control box, where it splits up to go to each switch,  which then goes back through the other 24 pins in the wire to each lighting district, then is split to go through each light (plus resistor/pot) in the district, then all lights on the layout come back to the one ground wire, or a few ground wires that all connect to the same 0V side of the power supply.  I can mock up a schematic later this evening if you think it would be helpful.  This method also allows you to add a pot to the +12 before it splits to all the switches, allowing you to have a master dimmer for the whole layout.

[gavino200]

Another question: Does anyone know the relevant formulas to calculate how many LEDs can be powered by a single 12V  transformer? It's a while since I've taken a physics class.

Edited April 6, 2017 by gavino200

[gavino200]

Yep, so the power would go from +12V on power supply through pin one on the wire to the control box, where it splits up to go to each switch,  which then goes back through the other 24 pins in the wire to each lighting district, then is split to go through each light (plus resistor/pot) in the district, then all lights on the layout come back to the one ground wire, or a few ground wires that all connect to the same 0V side of the power supply.  I can mock up a schematic later this evening if you think it would be helpful.  This method also allows you to add a pot to the +12 before it splits to all the switches, allowing you to have a master dimmer for the whole layout.

 

Thanks. Yes, a mock up schematic would be awesome.

 

I agree, a pot on the common supply before the split is a great idea. 

[Madsing]

Another remark: LEDs connected in parallel should each have their own resistor (including the indicator LEDs).

For more details: http://www.ledsupply.com/blog/#article/931

 

 

 

Sent from my iPhone using Tapatalk

[Kiha66]

Didn't have a lot of time, so please excuse the poor quality.  Hope this kinda shows what I was talking about, although I'm sure it has many errors.  

[kvp]

These could come handy:

http://led.linear1.org/1led.wiz

http://led.linear1.org/led.wiz

[cteno4]

Gavin,

 

That depends on how bright you want them and what milliamperes you are running the leds at. Most small leds are 20ma max so you can basically use that as a max so a 1A supply can run 50 leds if they are all wired individually. If you use 5v then less total wattage used than 12v source as you are burning the extra 7v in the resistors (instead of 2v) if you wire them individually. With 12v supply you can wire 3 white leds in series with a dropping resistor. Here each set of series leds draw 20ma so you can get 3x the leds from a 1A 12v power supply (the power is burned by the extra leds instead of higher value resistors.)

 

Make sense?

 

Jeff

[Kiha66]

Well I wasn't too happy with my sketch, so I made a digital version of my idea for the board design.  Hope this is a little easier to follow.

[gavino200]

Well I wasn't too happy with my sketch, so I made a digital version of my idea for the board design.  Hope this is a little easier to follow.

Layout Lighting Rough 1.png

 

Thank you so much for taking the time. That's awesome. I really like it. It's much simpler (and smarter) than what I had in mind. I like that the transformer goes directly layout rather than the panel. You rock Kiha!

[gavino200]

These could come handy:

http://led.linear1.org/1led.wiz

http://led.linear1.org/led.wiz

Great resourse kvp. Thanks!

[gavino200]

Gavin,

 

That depends on how bright you want them and what milliamperes you are running the leds at. Most small leds are 20ma max so you can basically use that as a max so a 1A supply can run 50 leds if they are all wired individually. If you use 5v then less total wattage used than 12v source as you are burning the extra 7v in the resistors (instead of 2v) if you wire them individually. With 12v supply you can wire 3 white leds in series with a dropping resistor. Here each set of series leds draw 20ma so you can get 3x the leds from a 1A 12v power supply (the power is burned by the extra leds instead of higher value resistors.)

 

Make sense?

 

Jeff

 

Yes, it does - generally. I think I'll have to bust out the equations and draw some examples for it to really click. As I remember it's not too hard. V=IR, P=I squared R, Kerchoff's laws for adding currents, etc

 

It's not so much of an immediate issue given Kiha's improved circuit design. My main goal was to estimate how many transformer connector jacks I had to make room for on the panel. But now the power supply is going directly to the layout Lighting bus.

 

I'm still going to do the math. Partly for planning. Partly out of interest/curiousity. Maybe it's just physics nostalgia. Is there such a thing?

[gavino200]

One more issue I thought of. It might be a good idea to apply some sort of clear wrap to the breadboards to protect from shorts and shocks. Something like a giant shrink wrap or a silicone sheet with holes cut for the pot, switch and indicator LED. I'm going to research it but if anyone knows of a suitable product or material I'd love to hear it.

[kvp]

Imho the group status indicator leds should be connected parallel like the rest with their own resistors. Otherwise the full group current will flow through them and they would be bright as hell or just burn out.

[cteno4]

Gavin,

 

Might think modular on this and just do them in like 1A blocks and the add on as you do more.

 

When you add a big pot to dim a whole block you do want dropping resistors for each led (or set of led in series) as wiring leds in parallel to one pot can cause issues if one led draws more current than the others. Also these big main pots will need to potentially suck up a lot of power from the leds and this would be up to 3 watts.

 

I like the idea of just putting small pots into the structure to dim each led or set of serial leds. That way each structure can easily be tuned and not a mass of working back to a master control panel. Just connect the structures up to a power buss. You could do block busses and just flip them on/off at the control panel and add indicator leds. The General dimmer is a great idea ot play with lighting on in daylight vs night as well. Most building have a fair amount of lights on during the day and it effects how the windows look. To get the effect in models (lighting does not scale well) different light levels may be needed to get the best effect for day or night.

 

Not sure what you are worried about shorting on the breadboards. I've just hotglued a bit of fun foam (that 2mm foam rubber that's cheap at craft stores) or heavy scrapbooking paper to the back of a pc board if there is a chance it will be around exposed metal. But I would just screw any pc boards to the underside of your panel with the solder nibs toward the panel. It may be a lot of work to set big pots and indicator leds on the board the drill holes in the panel to have the pc board mounted directly behind. May be easier tomjst put short leads onto the indicator leds and big pots and pop them thru the holes in the panel where ever you mount them.

 

Btw these are great with 3mm led for panels

 

http://www.ebay.com/itm/3mm-5mm-8mm-10mm-LED-Light-Lamp-Diode-Holder-Black-Plastic-LED-Clip-Bezel-Mount-/131892577214?var=&hash=item1eb56903be:m:mT2vM1P0dxOgNJuPhGi-ZPQ

 

Taller and fancier

 

http://www.ebay.com/itm/10Pcs-3MM-Round-Chrome-Metal-Plastic-LED-Lamp-Light-Emitting-Diode-Bezel-Holder-/361943265908?hash=item54457ff274:g:lS0AAOSwXYtY4O4i

 

Serial cables can be a great way to take a bunch of low amp lines out to your layout for lighting. They are getting harder to find and also you want ones that the jacket is not moulded onto the individual wire insulation as it's hard to separate out the wires when you cut the cable. Again to reduce this wiring I'm a fan of putting all the specific dimming circuits into the structure andnjust feed it power froma main bus, much simpler wire tracing and running, while cool to have a master board to set each light it's a nightmare of wiring!

 

Jeff

[gavino200]

Imho the group status indicator leds should be connected parallel like the rest with their own resistors. Otherwise the full group current will flow through them and they would be bright as hell or just burn out.

 

Thanks. Good point.

[gavino200]

Gavin,

 

Might think modular on this and just do them in like 1A blocks and the add on as you do more.

 

When you add a big pot to dim a whole block you do want dropping resistors for each led (or set of led in series) as wiring leds in parallel to one pot can cause issues if one led draws more current than the others. Also these big main pots will need to potentially suck up a lot of power from the leds and this would be up to 3 watts.

 

I like the idea of just putting small pots into the structure to dim each led or set of serial leds. That way each structure can easily be tuned and not a mass of working back to a master control panel. Just connect the structures up to a power buss. You could do block busses and just flip them on/off at the control panel and add indicator leds. The General dimmer is a great idea ot play with lighting on in daylight vs night as well. Most building have a fair amount of lights on during the day and it effects how the windows look. To get the effect in models (lighting does not scale well) different light levels may be needed to get the best effect for day or night.

 

Not sure what you are worried about shorting on the breadboards. I've just hotglued a bit of fun foam (that 2mm foam rubber that's cheap at craft stores) or heavy scrapbooking paper to the back of a pc board if there is a chance it will be around exposed metal. But I would just screw any pc boards to the underside of your panel with the solder nibs toward the panel. It may be a lot of work to set big pots and indicator leds on the board the drill holes in the panel to have the pc board mounted directly behind. May be easier tomjst put short leads onto the indicator leds and big pots and pop them thru the holes in the panel where ever you mount them.

 

Btw these are great with 3mm led for panels

 

http://www.ebay.com/itm/3mm-5mm-8mm-10mm-LED-Light-Lamp-Diode-Holder-Black-Plastic-LED-Clip-Bezel-Mount-/131892577214?var=&hash=item1eb56903be:m:mT2vM1P0dxOgNJuPhGi-ZPQ

 

Taller and fancier

 

http://www.ebay.com/itm/10Pcs-3MM-Round-Chrome-Metal-Plastic-LED-Lamp-Light-Emitting-Diode-Bezel-Holder-/361943265908?hash=item54457ff274:g:lS0AAOSwXYtY4O4i

 

Serial cables can be a great way to take a bunch of low amp lines out to your layout for lighting. They are getting harder to find and also you want ones that the jacket is not moulded onto the individual wire insulation as it's hard to separate out the wires when you cut the cable. Again to reduce this wiring I'm a fan of putting all the specific dimming circuits into the structure andnjust feed it power froma main bus, much simpler wire tracing and running, while cool to have a master board to set each light it's a nightmare of wiring!

 

Jeff

 

Wow. Lot's of great information. I had to read it a few times to understand it all. 

 

1. Yes, I want make this a modular project. I'm starting with one zone, but designing the panel for future expansion as we do more modeling. I'll have to review a bit before I can understand what you mean by a 'one amp block'. Do you mean to add a big enough resistor to the 12V power source to bring the current down to one amp? Then lowering the limiting resistor when adding new 'one amp blocks'. This seems reasonable. I'm guessing the goal is to avoid burning out components with high currents.

 

2. I agree about adding LEDs to each sub circuit. There needs to be something to protect the LEDs when all pots are set to minimum. The idea would be to have a duel pot system. One pot for the whole zone (maybe for day/night) and one pot for each sub circuit (mostly for play). 

 

3. I agree that your way of doing the wiring with local control in the structures is more sensible and efficient. The way I'm planning to do it is sheer madness. But we think it will be fun, so it's the plan, if we can pull it off.

 

4. You're right about the shorts. I forgot that the wires go behind the breadboard. 

 

5. I'm not completely sure I understand what your're saying in this sentence.

 

"But I would just screw any pc boards to the underside of your panel with the solder nibs toward the panel. It may be a lot of work to set big pots and indicator leds on the board the drill holes in the panel to have the pc board mounted directly behind. May be easier tomjst put short leads onto the indicator leds and big pots and pop them thru the holes in the panel where ever you mount them"

 

Are you talking about having the breadboards under the panel and just the switches and instruments poking through? I hadn't thought of doing that, but it would be pretty cool. That would make the underside a bit rough though, if it wasn't mounted on a surface. I guess I could also put the boards and wires on the top surface of the panel and then put a thin top layer over it with the switches/LEDs poking through. I could drill and hollow the top layer as I add more zones.

 

6. Thanks. I love the LED sockets. Will be using them.

 

7. Thanks for the heads up about the serial cable. I'll fine some and experiment. But they seem perfect unless I learn of a better option. They even look like they'd stack well.

 

Edit: I shouldn't have to worry about separating out component wires if I use Kiha's breakout boards. One breakout board on the the control panel, one breakout board on the layout, and a serial cable linking them.

 

http://www.ebay.com/itm/DB25-M2-01-Female-Port-Signal-Module-Terminal-Breakout-Board-Screw-Nut-Connector-/152407610061?hash=item237c3392cd:g:hncAAOSw4DJYhjS3

 

8. Yes, thanks for trying to talk me out of this insanity. I realize it will be a nightmare but I think it'll also be fun, and I think the little man will learn from it too.

Edited April 7, 2017 by gavino200

[cteno4]

Gavin

 

Small dia heatshrink is also your friend with wiring up panel leds and such. Just have to remeber to put it on the wire BEFORE you solder things!

 

http://www.ebay.com/itm/0-6MM-5-5MM-Polyolefin-2-1-Heat-Shrink-Tubing-Color-Selectable-5M-Lot-ROHS-UL-/192141088033?var=&hash=item2cbc805521:m:mgo3FSwuwhK7grHG2QeC1rg

 

Jeff

[kvp]

I would have a suggestion for the control panel. If you just need a bunch of on-off switches and leds, then you can skip using any circuit boards and just get through hole mounted switches and led sockets. Then wire up the main buses with solid bare wires and use a dsub connector with a clamp on ribbon cable and solder each wire to the switch directly.

 

This is an image of a control panel by looking from the bottom. The leftmost colum is the group select, while each group has its members mounted in a row. Each group has a single group indicator light.

 

The red and blue vertical solid bare wires could be hotglued to the bottom of the panel, then the red horizontal solid bare wires threaded through the holes in the switch solder legs and soldered in. These would be held off the plate by the switches. The leds are glued into the holes and connected to the bare horizonal group wires, the other ends connected to the blue ground through their resistor. The output connector is a ribbon dsub connector with the ribbon strands pulled apart and soldered directly to their controlling switch. These wires are isolated and flexible, so they could be placed between the switches. If the plate is mounted in a box, the bare wires would be isolated by air from touching anything. The dsub connector could be mounted on the side frame of the box, allowing a removable (and optional) bottom.

 

The dsub will have one circuit for every pin with a common ground pin as the last one. A 9 pole connector could have 8 circuits this way, but there are larger dsub connectors. (i would suggest using the 25 pins variant) For layout cabling, routing the power wires directly and then gathering the grounds with a single thicker wire will save on soldering time and the amount of wires. If you have lots of leds, then the common ground connection could use more than one pin on the connector.

[inobu]

I have not done this YET!! but I think its a viable option. (This is why I lean toward Digitrax as they have a lot of components to work with).

 

Use a SEC8 and control the LED's via DCC. The SEC8 can control 32 LEDS, Normally they are used for signaling aspects but there is no reason you cannot us them for other things.

 

Using JMRI will allow you to control them via a computer and create a control panel on a screen. This is a lot easier than physically building one. If you dont like it you can redo it easily.

 

Also you can create scripts to operate the LED on a time table and much more.

 

Mounting a flat screen TV on the wall allows you to blend the control panel into the room and plus use it as a TV. ............win win

 

The table on the upper right shows the DCC address and which LED will illuminate based on the what condition is sent (closed or thrown). You can build a control panel in JMRI that has buttons that will send out the assigned address for a given LED. Notice that DRV6 position 4 is a flashing LED. With that address you can have lights flash based on your needs.

 

Inobu

 

 

 

Edited April 7, 2017 by inobu

[gavino200]

I would have a suggestion for the control panel. If you just need a bunch of on-off switches and leds, then you can skip using any circuit boards and just get through hole mounted switches and led sockets. Then wire up the main buses with solid bare wires and use a dsub connector with a clamp on ribbon cable and solder each wire to the switch directly.

 

This is an image of a control panel by looking from the bottom. The leftmost colum is the group select, while each group has its members mounted in a row. Each group has a single group indicator light.

control.png

 

The red and blue vertical solid bare wires could be hotglued to the bottom of the panel, then the red horizontal solid bare wires threaded through the holes in the switch solder legs and soldered in. These would be held off the plate by the switches. The leds are glued into the holes and connected to the bare horizonal group wires, the other ends connected to the blue ground through their resistor. The output connector is a ribbon dsub connector with the ribbon strands pulled apart and soldered directly to their controlling switch. These wires are isolated and flexible, so they could be placed between the switches. If the plate is mounted in a box, the bare wires would be isolated by air from touching anything. The dsub connector could be mounted on the side frame of the box, allowing a removable (and optional) bottom.

 

The dsub will have one circuit for every pin with a common ground pin as the last one. A 9 pole connector could have 8 circuits this way, but there are larger dsub connectors. (i would suggest using the 25 pins variant) For layout cabling, routing the power wires directly and then gathering the grounds with a single thicker wire will save on soldering time and the amount of wires. If you have lots of leds, then the common ground connection could use more than one pin on the connector.

 

That's very similar to Kiha's design. I guess great minds think alike. I'll be using a design very similar to these. I'd have to read through both very clearly to see the differences. Using break out boards makes separating the wires in the cable unnecessary.

 

I'm with you on the box design. I was heading toward this in my reply to Jeff when he suggested LED sockets and cut outs for the switches. I was thinking of building the panel on the board and covering it with a sort of lid that had holes cut in it. Perhaps I could have it so that it screws closed. Switches and indicators would protrude through the top. Pin connectors would face out the back.

 

I'm going to put all these ideas together and draw up a draft. Maybe you could chime in and critique it. I was hoping to get it done this weekend, but I'm on call for work and it looks like it'll be a busy weekend.