Date   
Re: Coach Lighting

Flash Gordon
 

Carl,

Yes I am looking into the same ideas, especially for reverse loop indicators.

But the question is why do you need a diode in series with a string of LED's inside a passenger coach. A resistor yes but why a diode?

Ed S


At 10:04 PM 1/29/2014, you wrote:
 

Hello Ed:

We use them as indicators for track power. I've put one on the town panel and also one on the distribution panel so I know where the power is. On the HO layout we use the frog power contacts to power LED signals. If I were wiring a layout from scratch one wire from the frog could power LED indicators on control panels. And they would be feeding back actual point position. At reversing loops we use the LEDs to indicate if the polarity is correct. LEDs don't draw much amperage so it really doesn't interfere with locomotive's motors, a big draw if they are running full.

Carl.

Re: Coach Lighting

Max Maginness
 

LED’s will stand only a few volts (5-7) in reverse from the normal polarity for lighting them. If on DCC they are under reverse voltage half the time. If you have 2 or 3 in series the reverse voltage might divide evenly, but very unlikely, so it’s best to prevent stressing the LED’s by adding a regular diode as well. These are usually have minimum reverse rating of at least 59 volts so more than adequate for DCC track voltage levels. And yes someone may be using them without diodes and so far nothing happened, but that’s no substitute for a little proper engineering.

 

Max

 

From: WiringForDCC@... [mailto:WiringForDCC@...] On Behalf Of Ed S
Sent: Wednesday, January 29, 2014 7:03 PM
To: WiringForDCC@...
Subject: Re: [WiringForDCC] Coach Lighting

 

 

So why do you need another diode in the circuit being discussed?

Ed S

At 09:21 PM 1/29/2014, you wrote:

 

Yep led is a diode ... Light Emitting Diode.
Andrew wood
Maffra, Victoria



On 30 Jan 2014, at 12:38, Ed S < eschwerkolt@...> wrote:


 

Aren't LED's actually diodes? I do not power anything from the DCC power so I don't know how it would work.  I am greedy and don't want to share it with the locos's.

I use a separate DC bus for accessories. I want it to be clean because I also power some electronics.

Ed S


No virus found in this message.
Checked by AVG - www.avg.com
Version: 10.0.1432 / Virus Database: 3684/6544 - Release Date: 01/29/14

Re: Coach Lighting

Flash Gordon
 

Max,

Thanks that makes sense. I will include a diode if I decide to power LEDs from the track.

Ed S

At 10:14 PM 1/29/2014, you wrote:


LED's will stand only a few volts (5-7) in reverse from the normal polarity for lighting them. If on DCC they are under reverse voltage half the time. If you have 2 or 3 in series the reverse voltage might divide evenly, but very unlikely, so it's best to prevent stressing the LED's by adding a regular diode as well. These are usually have minimum reverse rating of at least 59 volts so more than adequate for DCC track voltage levels. And yes someone may be using them without diodes and so far nothing happened, but that's no substitute for a little proper engineering.



Max

Re: Coach Lighting

Max Maginness
 

Just don’t look for a “59 volt” one  - my fumble fingering, I meant 50 volts (such as a 1N4001 or use any of the 1N400x series rated at successively higher reverse voltages.)

 

Max

 

From: WiringForDCC@... [mailto:WiringForDCC@...] On Behalf Of Ed S
Sent: Wednesday, January 29, 2014 7:40 PM
To: WiringForDCC@...
Subject: RE: [WiringForDCC] Coach Lighting

 

 

Max,

Thanks that makes sense. I will include a diode if I decide to power
LEDs from the track.

Ed S

At 10:14 PM 1/29/2014, you wrote:
>
>
>LED's will stand only a few volts (5-7) in reverse from the normal
>polarity for lighting them. If on DCC they are under reverse voltage
>half the time. If you have 2 or 3 in series the reverse voltage
>might divide evenly, but very unlikely, so it's best to prevent
>stressing the LED's by adding a regular diode as well. These are
>usually have minimum reverse rating of at least 59 volts so more
>than adequate for DCC track voltage levels. And yes someone may be
>using them without diodes and so far nothing happened, but that's no
>substitute for a little proper engineering.
>
>
>
>Max
>
>


No virus found in this message.
Checked by AVG - www.avg.com
Version: 10.0.1432 / Virus Database: 3684/6544 - Release Date: 01/29/14

Re: Coach Lighting

Joseph Pyland <jpyland@...>
 

Ed,

 

Your getting caught up on the name, an LED will only work in one direction, hence the word diode in the name.  However, they will not work to stop “back” voltage/reverse voltage, most of the LEDs today the reverse voltage is half or less of the forward voltage.  The standard diode has anywhere from equal to up to normally four times the back voltage, and I say normally because I find one with, if I remember right it was 10 to 12 times the back voltage, but I am not spending $182 for a diode.  Remember the resistor only limits current not voltage, so the EE’s tell me, I never understood that completely.

 

Joe Pyland

Hewitt TX

 

 

From: WiringForDCC@... [mailto:WiringForDCC@...] On Behalf Of Ed S
Sent: Wednesday, January 29, 2014 21:03
To: WiringForDCC@...
Subject: Re: [WiringForDCC] Coach Lighting

 

 

So why do you need another diode in the circuit being discussed?

Ed S

At 09:21 PM 1/29/2014, you wrote:

 

Yep led is a diode ... Light Emitting Diode.
Andrew wood
Maffra, Victoria



On 30 Jan 2014, at 12:38, Ed S < eschwerkolt@...> wrote:


 

Aren't LED's actually diodes? I do not power anything from the DCC power so I don't know how it would work.  I am greedy and don't want to share it with the locos's.

I use a separate DC bus for accessories. I want it to be clean because I also power some electronics.

Ed S

LM317 Circuits

William E. Davies <wedavies@...>
 

Greetings group,
Perhaps the attached info will make the LM317 more useful.
Bill

Re: Coach Lighting

Andrew Wood
 

You would have a current protection diode on the positive side to stop back current and a resistor to limit current to fire the LED at the correct voltage.

Andrew W


On 30 Jan 2014, at 14:02, Ed S <eschwerkolt@...> wrote:

 

So why do you need another diode in the circuit being discussed?

Ed S

At 09:21 PM 1/29/2014, you wrote:

 

Yep led is a diode ... Light Emitting Diode.
Andrew wood
Maffra, Victoria



On 30 Jan 2014, at 12:38, Ed S < eschwerkolt@...> wrote:

 

Aren't LED's actually diodes? I do not power anything from the DCC power so I don't know how it would work.  I am greedy and don't want to share it with the locos's.

I use a separate DC bus for accessories. I want it to be clean because I also power some electronics.

Ed S

Re: Coach Lighting

Chris Richter
 

Use: http://www.proto87.com/


Chris

Re: Coach Lighting

John Cahill
 

Hi Alden, this only shows a hosting site??

Best Regards,
John

On Jan 29, 2014, at 23:37, "Alden G. McBee" <agm@...> wrote:

 

Check out flex-lighting on www.proto87stores.com.

—Alden McBee

On Jan 29, 2014, at 1:25 PM, John Cahill <johncahill25@...> wrote:


Hi! I am investigating the multiple possible methods of lighting coaches/carriages on my HO NCE controlled layout.  I have tried Flicker Free, which works fine.  I have also built small circuits using miniature rectifiers feeding LED strips.  In order to light my entire collection using any of these methods, a significant investment in time and electronic components would be required.  I have tried a small experiment using direct DCC track power to light a short strip of LED lights and found it worked fine, especially with the addition of a 1K resistor in series in the circuit.  Is this approach too simplistic or am I missing something?  Any comments appreciated!  Thanks in advance,
John Cahill


Re: Coach Lighting

John Cahill
 

Thanks Everyone for your helpful suggestions. I'm learning slowly! Will now add 1N4001's + resistor in circuit. 
Can anyone add thoughts on using super capacitors in the circuit for flicker free operation instead of a battery?

Best Regards,
John

On Jan 29, 2014, at 22:11, John Cahill <johncahill25@...> wrote:

Thanks John. I'm using DCC and a strip of LEDs, about 12 diodes on strip (varies for different makes of coach).  I'm a bit unsure how to calculate current draw other than measuring it as no data sheet for LEDs in question. From that I can get wattage, right?
I also have some supercapacitors I'd like to use to eliminate flicker, but they are rated 5.6V, I believe. Is there a way to work them into the circuit or is that a bridge (no pun intended) too far?

Best Regards,
John

On Jan 29, 2014, at 19:34, john.p.dunn@... wrote:

 

John,
   Unless you add a battery (like Spectrum cars), your only option is track power. If you run your cars on DC you will have to power your lamps through a rectifier and use a capacitor to keep the brightness constant. On DCC, forget the rectifier and if you use LEDs you just need a resistor. They are their own rectifier. Bulbs draw more current usually and need a heavier wattage resistor.
   You need to know the wattage, amps and volts of your lamps and use Ohm's law to figure your resister and the total wattage tells you the size resistor you need (1/8, 1/4, 1/2 watt and the resistance in ohms.
   Another option is to put LEDs or bulbs in series to equal your track voltage, of course if one bulb goes you are in the dark.
   Hope it helps.
john

 From: John Cahill <johncahill25@...>
To: WiringForDCC@...
Sent: Wednesday, January 29, 2014 1:25 PM
Subject: [WiringForDCC] Coach Lighting



Hi! I am investigating the multiple possible methods of lighting coaches/carriages on my HO NCE controlled layout.  I have tried Flicker Free, which works fine.  I have also built small circuits using miniature rectifiers feeding LED strips.  In order to light my entire collection using any of these methods, a significant investment in time and electronic components would be required.  I have tried a small experiment using direct DCC track power to light a short strip of LED lights and found it worked fine, especially with the addition of a 1K resistor in series in the circuit.  Is this approach too simplistic or am I missing something?  Any comments appreciated!  Thanks in advance,
John Cahill




Re: Coach lighting

Tom Cockle
 

I use a bridge rectifier ahead of the LED lighting (so that when I run at my DC-only club the lights work in both directions).   Since a bridge rectifier is actually four diodes, doesn't this solve the reverse voltage problem as well?
Or should I add another diode?
Tom Cockle
McKinleyville CA


Re: Coach Lighting

Wed Jan 29, 2014 7:39 pm (PST) . Posted by:

"Ed S" ed.kolt

Max,

Thanks that makes sense. I will include a diode if I decide to power 
LEDs from the track.

Ed S


At 10:14 PM 1/29/2014, you wrote:
>
>
>LED's will stand only a few volts (5-7) in reverse from the normal 
>polarity for lighting them. If on DCC they are under reverse voltage 
>half the time. If you have 2 or 3 in series the reverse voltage 
>might divide evenly, but very unlikely, so it's best to prevent 
>stressing the LED's by adding a regular diode as well. These are 
>usually have minimum reverse rating of at least 59 volts so more 
>than adequate for DCC track voltage levels. And yes someone may be 
>using them without diodes and so far nothing happened, but that's no 
>substitute for a little proper engineering.
>
>
>
>Max

Re: Coach Lighting

Michael Looney
 

The web site address is www.proto87.com it doesn't have the store name in the web site.
 Mike Looney
 
 

On 01/29/14, Douglas Krahn wrote:
 
 

The link to  http://www.proto87stores.com/. didn't work Only got a hosting service.

Doug K
From: Alden G. McBee <agm@...>
To: WiringForDCC@...
Sent: Wednesday, January 29, 2014 5:37 PM
Subject: Re: [WiringForDCC] Coach Lighting
 
Check out flex-lighting on http://www.proto87stores.com/.
—Alden McBee
On Jan 29, 2014, at 1:25 PM, John Cahill <johncahill25@...> wrote:

Hi! I am investigating the multiple possible methods of lighting coaches/carriages on my HO NCE controlled layout.  I have tried Flicker Free, which works fine.  I have also built small circuits using miniature rectifiers feeding LED strips.  In order to light my entire collection using any of these methods, a significant investment in time and electronic components would be required.  I have tried a small experiment using direct DCC track power to light a short strip of LED lights and found it worked fine, especially with the addition of a 1K resistor in series in the circuit.  Is this approach too simplistic or am I missing something?  Any comments appreciated!  Thanks in advance,
John Cahill

Re: Coach Lighting

Vollrath, Don <dvollrath@...>
 

John, Your initial description indicates that you may be using ‘miniature rectifiers feeding LED strips’. If you use a full wave (4 diode) rectifier circuit between track pick-up and the LED strip you already have what is required.. except adding of a resistor to vary the brightness. What can also be done to help reduce flicker is to provide a carry-over storage capacitor. Circuit wise this means to add a relatively large capacitor, rated for 25V and several thousand microfarads, using a 100 ohm resistor to limit charging current from the rectified track voltage and a diode connected to supply current from the capacitor toward the LED strip through the brightness adjusting resistor. This may be enough to eliminate annoying flicker.

DonV

 

From: WiringForDCC@... [mailto:WiringForDCC@...] On Behalf Of John Cahill
Sent: Wednesday, January 29, 2014 1:31 PM
To: WiringForDCC@...
Subject: Re: [WiringForDCC] Coach Lighting

 




Thanks, Don.  Does it matter which direction the diode faces?

John C

 

On Wed, Jan 29, 2014 at 6:59 PM, Vollrath, Don <dvollrath@...> wrote:

 

Don’t forget to include a diode to protect the LED strip from reverse voltage. (if it doesn’t already include a rectifier.) Use a single resistor to limit current and brightness.

DonV

 

From: WiringForDCC@... [mailto:WiringForDCC@...] On Behalf Of John Cahill
Sent: Wednesday, January 29, 2014 12:25 PM
To: WiringForDCC@...
Subject: [WiringForDCC] Coach Lighting

 



Hi! I am investigating the multiple possible methods of lighting coaches/carriages on my HO NCE controlled layout.  I have tried Flicker Free, which works fine.  I have also built small circuits using miniature rectifiers feeding LED strips.  In order to light my entire collection using any of these methods, a significant investment in time and electronic components would be required.  I have tried a small experiment using direct DCC track power to light a short strip of LED lights and found it worked fine, especially with the addition of a 1K resistor in series in the circuit.  Is this approach too simplistic or am I missing something?  Any comments appreciated!  Thanks in advance,

John Cahill



 




Power Pax ?

terryintexas7@...
 

Is there a way to test a power pax booster to tell if it's working properly
 
Thanks
Terry

Re: Coach Lighting

John Cahill
 

Don, I may have mis-described initially.  I was trying NO rectification and feeding direct track DCC voltage into the LED strip.  You have explained the need for a 50V diode in line with a suitable rated resistor to that circuit to protect the LEDs.  I will use this going forward. Don't really want to put a big cap in coaches (weight, size, cost factors}. However, I recall a drawing of a lighting circuit I found on line a few years ago which showed a zener across the rectifier outputs and a small supercap in parallel for flicker free lighting.  Does this make sense?  Voltage was around 5.5V out of zener, if I remember correctly, but my knowledge of electronics is rather basic, I'm afraid.
Regards,
John


On Thu, Jan 30, 2014 at 7:52 AM, John Cahill <johncahill25@...> wrote:
Thanks Everyone for your helpful suggestions. I'm learning slowly! Will now add 1N4001's + resistor in circuit. 
Can anyone add thoughts on using super capacitors in the circuit for flicker free operation instead of a battery?

Best Regards,
John

On Jan 29, 2014, at 22:11, John Cahill <johncahill25@...> wrote:

Thanks John. I'm using DCC and a strip of LEDs, about 12 diodes on strip (varies for different makes of coach).  I'm a bit unsure how to calculate current draw other than measuring it as no data sheet for LEDs in question. From that I can get wattage, right?
I also have some supercapacitors I'd like to use to eliminate flicker, but they are rated 5.6V, I believe. Is there a way to work them into the circuit or is that a bridge (no pun intended) too far?

Best Regards,
John

On Jan 29, 2014, at 19:34, john.p.dunn@... wrote:

 

John,
   Unless you add a battery (like Spectrum cars), your only option is track power. If you run your cars on DC you will have to power your lamps through a rectifier and use a capacitor to keep the brightness constant. On DCC, forget the rectifier and if you use LEDs you just need a resistor. They are their own rectifier. Bulbs draw more current usually and need a heavier wattage resistor.
   You need to know the wattage, amps and volts of your lamps and use Ohm's law to figure your resister and the total wattage tells you the size resistor you need (1/8, 1/4, 1/2 watt and the resistance in ohms.
   Another option is to put LEDs or bulbs in series to equal your track voltage, of course if one bulb goes you are in the dark.
   Hope it helps.
john

 From: John Cahill <johncahill25@...>
To: WiringForDCC@...
Sent: Wednesday, January 29, 2014 1:25 PM
Subject: [WiringForDCC] Coach Lighting



Hi! I am investigating the multiple possible methods of lighting coaches/carriages on my HO NCE controlled layout.  I have tried Flicker Free, which works fine.  I have also built small circuits using miniature rectifiers feeding LED strips.  In order to light my entire collection using any of these methods, a significant investment in time and electronic components would be required.  I have tried a small experiment using direct DCC track power to light a short strip of LED lights and found it worked fine, especially with the addition of a 1K resistor in series in the circuit.  Is this approach too simplistic or am I missing something?  Any comments appreciated!  Thanks in advance,
John Cahill





Re: Coach Lighting

Flash Gordon
 

Re: Coach Lighting

Vollrath, Don <dvollrath@...>
 

John, what I don’t know is what is inside the LED light strips you have in your hand. I’m guessing that there are 4 or 5 LEDs wired in series with a current limiting resistor (or maybe an active current regulator IC, NOT the same as a voltage regulator) with the intention of the strip being powered from 12-14Vdc (think auto-car battery). There probably is a (+) or (-) mark where you are to attach power wires. Yes, each LED is indeed a diode supposedly to conduct current on only one direction. However as others have pointed out the rated reverse breakdown voltage of each LED is limited… and particularly low for blue and white ones. If/When voltage is applied in the reverse direction, like directly from DCC on the rails, which is actually alternating in polarity, some current may flow backwards through the parts. It may appear to work OK for a long time or they may fail catastrophically without warning. One way to prevent that is to put some sort of rectifier in the circuit so as to protect the LED cells against reverse voltage and current flow. There may already be a diode or other protective device inside the lighting strip.

 

Either way… To add a flicker-free power carry-over mechanism, you have only three choices: 1) purchase some commercial product and pay their price or 2) utilize independent battery power or 3) become a D-I-Y expert enough to figure out what is inside the LED strip and come up with an external carry-over mechanism using readily available low cost components. The thought of using a 5.5V supercap is a good one, but you are not going to get more than 2 LEDs in series to light up [If you try this don’t forget the series resistor to limit current.] You will need to trace out the circuitry inside the lighting strip to be able to cut PCB traces to connect directly to 1, 2 or possibly 3 LED cells and wire them up to external circuits.

 

Each external circuit should start with a 50V rated full wave rectifier with the AC inputs attached to power pick-ups from the truck(s). the DC side of the rectifier needs to power the charger for the supercap or rechargeable battery. It must be current limited and have over-voltage protection for the supercap or battery (whatever that maximum working voltage may be) to protect from catastrophic failure of the storage cell. Yes a good method is to place a zener diode across the battery or supercap. From the storage cell, supercap or battery, there needs to be a current limiting resistor in series with the 1, 2 or possibly 3 LEDs to light and control current. Adjust the resistor to determine lighting intensity. LED current is likely to be 8-20 milliamps. For more LEDs in the same coach, connect up multiple LED and resistor circuits as just described in parallel to be powered from the energy storage cell. Sounds simple enough, but without knowing anything else about what components you are likely to use and their maximum voltage rating it is difficult to show actual wiring or resistor values.

 

Good luck

Contact me directly by email if you wish

DonV

 

From: WiringForDCC@... [mailto:WiringForDCC@...] On Behalf Of John Cahill
Sent: Thursday, January 30, 2014 11:57 AM
To: WiringForDCC@...
Subject: Re: [WiringForDCC] Coach Lighting

 




Don, I may have mis-described initially.  I was trying NO rectification and feeding direct track DCC voltage into the LED strip.  You have explained the need for a 50V diode in line with a suitable rated resistor to that circuit to protect the LEDs.  I will use this going forward. Don't really want to put a big cap in coaches (weight, size, cost factors}. However, I recall a drawing of a lighting circuit I found on line a few years ago which showed a zener across the rectifier outputs and a small supercap in parallel for flicker free lighting.  Does this make sense?  Voltage was around 5.5V out of zener, if I remember correctly, but my knowledge of electronics is rather basic, I'm afraid.

Regards,

John

 

On Thu, Jan 30, 2014 at 7:52 AM, John Cahill <johncahill25@...> wrote:

Thanks Everyone for your helpful suggestions. I'm learning slowly! Will now add 1N4001's + resistor in circuit. 

Can anyone add thoughts on using super capacitors in the circuit for flicker free operation instead of a battery?

Best Regards,

John


On Jan 29, 2014, at 22:11, John Cahill <johncahill25@...> wrote:

Thanks John. I'm using DCC and a strip of LEDs, about 12 diodes on strip (varies for different makes of coach).  I'm a bit unsure how to calculate current draw other than measuring it as no data sheet for LEDs in question. From that I can get wattage, right?

I also have some supercapacitors I'd like to use to eliminate flicker, but they are rated 5.6V, I believe. Is there a way to work them into the circuit or is that a bridge (no pun intended) too far?

Best Regards,

John


On Jan 29, 2014, at 19:34, john.p.dunn@... wrote:

 

John,

   Unless you add a battery (like Spectrum cars), your only option is track power. If you run your cars on DC you will have to power your lamps through a rectifier and use a capacitor to keep the brightness constant. On DCC, forget the rectifier and if you use LEDs you just need a resistor. They are their own rectifier. Bulbs draw more current usually and need a heavier wattage resistor.

   You need to know the wattage, amps and volts of your lamps and use Ohm's law to figure your resister and the total wattage tells you the size resistor you need (1/8, 1/4, 1/2 watt and the resistance in ohms.

   Another option is to put LEDs or bulbs in series to equal your track voltage, of course if one bulb goes you are in the dark.

   Hope it helps.

john

 

 From: John Cahill <johncahill25@...>
To: WiringForDCC@...
Sent: Wednesday, January 29, 2014 1:25 PM
Subject: [WiringForDCC] Coach Lighting

 

 

Hi! I am investigating the multiple possible methods of lighting coaches/carriages on my HO NCE controlled layout.  I have tried Flicker Free, which works fine.  I have also built small circuits using miniature rectifiers feeding LED strips.  In order to light my entire collection using any of these methods, a significant investment in time and electronic components would be required.  I have tried a small experiment using direct DCC track power to light a short strip of LED lights and found it worked fine, especially with the addition of a 1K resistor in series in the circuit.  Is this approach too simplistic or am I missing something?  Any comments appreciated!  Thanks in advance,

John Cahill

 

 

 




Re: Coach Lighting

William E. Davies <wedavies@...>
 



Try proto87.com.


On 29-Jan-14 18:47, Douglas Krahn wrote:
 
The link to  http://www.proto87stores.com/. didn't work Only got a hosting service.

Doug K
From: Alden G. McBee
To: WiringForDCC@...
Sent: Wednesday, January 29, 2014 5:37 PM
Subject: Re: [WiringForDCC] Coach Lighting
 
Check out flex-lighting on http://www.proto87stores.com/.
—Alden McBee
On Jan 29, 2014, at 1:25 PM, John Cahill <johncahill25@...> wrote:

Hi! I am investigating the multiple possible methods of lighting coaches/carriages on my HO NCE controlled layout.  I have tried Flicker Free, which works fine.  I have also built small circuits using miniature rectifiers feeding LED strips.  In order to light my entire collection using any of these methods, a significant investment in time and electronic components would be required.  I have tried a small experiment using direct DCC track power to light a short strip of LED lights and found it worked fine, especially with the addition of a 1K resistor in series in the circuit.  Is this approach too simplistic or am I missing something?  Any comments appreciated!  Thanks in advance,
John Cahill


Re: Coach Lighting

Carl
 

Hi Gang:

You can buy as many as you want from All-Electronics for $0.40 each:

http://www.allelectronics.com/make-a-store/item/FWB-14/1.5-AMP-200-VOLT-FULL-WAVE-BRIDGE-RECTIFIER/1.html

They have several, all under a dollar.

Or you might find them for free inside that old VCR you have laying around.

Carl.

On 1/30/2014 1:51 PM, Ed S wrote:
 

LM317 Info

William E. Davies <wedavies@...>
 

Perhaps the attached .pdf file will be helpful. I found it very good.
Bill