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Re: Bi-Polar Red /Green LEDs in Control Panels.

Tom Jones
 

Don, the wiring you suggested is how they are currently (pun intended) wired per the circuitron diagram. My problem is in parallel most of  the current is consumed by the red side of each LED. Running the Leds in series does not help and slows the tortoise movement to a crawl.. My solution I think  as suggested is to try and source a bi-LED that has a closer tolerance between the Red and Green outputs. Fortunately or "un" I am headed to the mountains for the next few days and will have a look when I get back.


Re: Bi-Polar Red /Green LEDs in Control Panels.

Carl
 

Hi Gang:

When I was building my turnout motors I used a breadboard like this to test for component values:


SOLDERLESS BREADBOARD, 400 CONTACTS

https://www.allelectronics.com/item/pb-400/solderless-breadboard-400-contacts/1.html

Didn't have problems with the resistors for the LEDs, but did have to add a capacitor to keep the relay from chattering. It is a lot easier to test and fix on the bench, instead of under the layout.

Carl.

On 7/1/2020 1:16 AM, Don Vollrath wrote:

Tom Jones, use two of the R/G 2 lead LEDs But connect each of them in opposition series with each other and with one of the Tortoise motor leads. Wire both of the short (or long) leads of the LEDs together. And the opposite pair in series with the motor. Current then will always flow through one Red, and one Green, and be limited by the resistance of the Motor. 

DonV


Re: Bi-Polar Red /Green LEDs in Control Panels.

Don Vollrath
 

Tom Jones, use two of the R/G 2 lead LEDs But connect each of them in opposition series with each other and with one of the Tortoise motor leads. Wire both of the short (or long) leads of the LEDs together. And the opposite pair in series with the motor. Current then will always flow through one Red, and one Green, and be limited by the resistance of the Motor. 

DonV


Re: Bi-Polar Red /Green LEDs in Control Panels.

 

Max is absolutely correct in that it is current.  If we are talking about a single 2 wire LED that is red when current flows in one direction and green when it flows in the other then it is the fault of the maker to not balance the brightness.

A work around would be to use a different resistor for each direction.  Connect each resistor to a diode in series.  Now connect the resistors and diodes in parallel with the diodes pointing in opposite direction.  Now the current only flows through one resisotr for each polarity.  Now swap out one of the resistors until the brightness is correct.

Best Regards,
Ken Harstine


Re: Bi-Polar Red /Green LEDs in Control Panels.

Max Maginness
 

Mind sending me a circuit sketch of this?

 

Max

 

From: w4dccqa@groups.io <w4dccqa@groups.io> On Behalf Of Tom Jones
Sent: Tuesday, June 30, 2020 6:10 AM
To: w4dccqa@groups.io
Subject: Re: [w4dccqa] Bi-Polar Red /Green LEDs in Control Panels.

 

Max, Thomas is correct. Two bi-color in parallel and in reverse direction. The control panel indication is green for route selected, red for not selected.

   Thomas, thank you  for the voltage information on the LEDs. I was not aware of that. I must have gotten lucky years ago when I initially started buying my bi-colors and building control panels. I am out the door camping for a couple days but Friday will investigate Jameco's LEDS and post  my findings.  Thank everyone for there input to the problem. ...tj


Re: Bi-Polar Red /Green LEDs in Control Panels.

Max Maginness
 

A diagram is needed!

Max

 

From: w4dccqa@groups.io <w4dccqa@groups.io> On Behalf Of thomasmclae via groups.io
Sent: Tuesday, June 30, 2020 7:58 AM
To: w4dccqa@groups.io
Subject: Re: [w4dccqa] Bi-Polar Red /Green LEDs in Control Panels.

 

Did you try soldering the LEDs in series with each other?
Tortoise left , LED, LED, Tortoise right. With LED short lead to short lead. That way the current path goes through both LEDs, one as red the other as green?
(Better with a diagram, which would take me about 3 days!)
Thomas
DeSoto, TX


Re: Bi-Polar Red /Green LEDs in Control Panels.

thomasmclae
 

Did you try soldering the LEDs in series with each other?
Tortoise left , LED, LED, Tortoise right. With LED short lead to short lead. That way the current path goes through both LEDs, one as red the other as green?
(Better with a diagram, which would take me about 3 days!)
Thomas
DeSoto, TX


Re: Bi-Polar Red /Green LEDs in Control Panels.

Tom Jones
 

Max, Thomas is correct. Two bi-color in parallel and in reverse direction. The control panel indication is green for route selected, red for not selected.
   Thomas, thank you  for the voltage information on the LEDs. I was not aware of that. I must have gotten lucky years ago when I initially started buying my bi-colors and building control panels. I am out the door camping for a couple days but Friday will investigate Jameco's LEDS and post  my findings.  Thank everyone for there input to the problem. ...tj


Re: Bi-Polar Red /Green LEDs in Control Panels.

Max Maginness
 

Are we getting confused between inserting the bi-color Led in series with one of wires powering the stall machine of either typed and connecting it across (between)  the leads with a resistor in series with the LED.

 

In either case the particular voltage spec of the R or G LED is almost irrelevant – it’s the current passing through them that determines the light output. The only situation where it might matter is if the LED’s are being driven from an very low voltage source like a 3 volt battery, but here we have 12 volts or so.

 

Max

 

From: w4dccqa@groups.io <w4dccqa@groups.io> On Behalf Of thomasmclae via groups.io
Sent: Monday, June 29, 2020 4:00 PM
To: w4dccqa@groups.io
Subject: Re: [w4dccqa] Bi-Polar Red /Green LEDs in Control Panels.

 

He is using a pair of red/green two wire LED. We have been using the same configuration for years.
Of the pair, one always shows red, the other green.
We use switchmaster motors, but works the same as Tortoises.
If you but from Jameco (Or non-rail sources) you need to verify that what you are buying has the same voltage for red and green. Otherwise, one color pulls all the amps and the other is dim.
And no way to add a resister to the 'red' as it is the same circuit. (Unless you do a bypass with a diode and resistor, but that would zap the motor (Tortoise) )

Post the Jameco part number, and lets see what the LED specs are,.


Re: Bi-Polar Red /Green LEDs in Control Panels.

thomasmclae
 

He is using a pair of red/green two wire LED. We have been using the same configuration for years.
Of the pair, one always shows red, the other green.
We use switchmaster motors, but works the same as Tortoises.
If you but from Jameco (Or non-rail sources) you need to verify that what you are buying has the same voltage for red and green. Otherwise, one color pulls all the amps and the other is dim.
And no way to add a resister to the 'red' as it is the same circuit. (Unless you do a bypass with a diode and resistor, but that would zap the motor (Tortoise) )

Post the Jameco part number, and lets see what the LED specs are,.


Re: Bi-Polar Red /Green LEDs in Control Panels.

Max Maginness
 

If you wire the two separate LED as shown on the instructions – that is in parallel, “pointing” in opposite directions, ( sometimes known as  reverse parallel) its  exactly the same electrically as if they were on the one 2 lead package.  Or are you somehow using two, single package two lead bi-color leds?

 

Max

 

 

 

From: w4dccqa@groups.io <w4dccqa@groups.io> On Behalf Of Tom Jones
Sent: Monday, June 29, 2020 12:55 PM
To: w4dccqa@groups.io
Subject: Re: [w4dccqa] Bi-Polar Red /Green LEDs in Control Panels.

 

Ron, yes a single 2-legged Bi-color red green LED will work and the green will light because it is the only LED getting voltage when DC flows it's direction. Th problem is when 2 Red/Green bi-color LEDs are wired in parallel back to back as on the tortoise discription the Red LED sucks all the power leaving the Green dim or almost not visible.  ..tj


Re: Bi-Polar Red /Green LEDs in Control Panels.

john
 

There are three lead, two color LEDs available and you bias each lead as necessary.

You can use two diodes in series (one reversed), with the bi-color LED and also series an appropriate resistor to dim the red light and another to bios both for the voltage. Remember the diodes cause a .6 volt drop to both colors so consider that in you math. 

Another option, I only light the turnout when it is diverged. 

Hope it helped.

jd


On Monday, June 29, 2020, 03:49:47 PM EDT, Tom Jones <tomjones4884@...> wrote:


Paul O;
 I am trying to source different LEDs. I would have to add a dropping resistor on both sides of the 2-legged bi-color LEDs (on the "red" side of each) and a lot of extra work. I wish I had a hundred more of the old ones.  ...tj


Re: Bi-Polar Red /Green LEDs in Control Panels.

Tom Jones
 

Ron, yes a single 2-legged Bi-color red green LED will work and the green will light because it is the only LED getting voltage when DC flows it's direction. Th problem is when 2 Red/Green bi-color LEDs are wired in parallel back to back as on the tortoise discription the Red LED sucks all the power leaving the Green dim or almost not visible.  ...tj


Re: Bi-Polar Red /Green LEDs in Control Panels.

Tom Jones
 

Paul O;
 I am trying to source different LEDs. I would have to add a dropping resistor on both sides of the 2-legged bi-color LEDs (on the "red" side of each) and a lot of extra work. I wish I had a hundred more of the old ones.  ...tj


Re: Bi-Polar Red /Green LEDs in Control Panels.

thomasmclae
 

You may have bought the wrong LED. Confusing as they all have 243 numbers to review.
Look at the LED voltage. It shows the volts for the red/green. Both voltages need to be the same, or one will be brighter. Jamco has voltage as a filter option.
If Red is 1.5 and green is 2.0, the red will be brighter at the same voltage.

Thomas
DeSoto, TX


Re: polarity reversing & block occupancy detector

Bob Macionis
 

Thanks, Carl.  Very Helpful!!  One dollar each is cheap!

 

Sent from Mail for Windows 10

 

From: Carl
Sent: Sunday, June 28, 2020 10:37 PM
To: w4dccqa@groups.io
Subject: Re: [w4dccqa] polarity reversing & block occupancy detector

 

Hi Bob:

I used relays like these in my turnout motors:

https://www.allelectronics.com/item/rly-587/5vdc-dpdt-2a-mini-relay/1.html

They have been working fine for 20 years.

Carl.

On 6/28/2020 5:05 PM, Bob Macionis wrote:

Thanks Carl/.  I’m not very knowledgeable about relays, but it seems to be a good answer.  Any particular characteristics of the relay I should look for?   My BD 20 block detectors have an output for a relay.

Bob

 

Sent from Mail for Windows 10

 

From: Carl
Sent: Sunday, June 28, 2020 3:18 PM
To: w4dccqa@groups.io
Subject: Re: [w4dccqa] polarity reversing & block occupancy detector

 

Hi Bob:

You could use the output to run a DPDT relay.

Carl.

On 6/28/2020 1:38 PM, Bob Macionis wrote:

I have lower quadrant semaphores controlled by tortoise machines.  I want the blades to move automatically when the block protected by the semaphores is occupied/unoccupied.   Is there an occupancy detector that reverses polarity of its output that would cause the tortoises to throw? Or maybe there is another way to auto throw the tortoises when a train enters/leaves the block?  Thanks for your advice.
Bob Macionis

 

 


Re: polarity reversing & block occupancy detector

Carl
 

Hi Bob:

I used relays like these in my turnout motors:

https://www.allelectronics.com/item/rly-587/5vdc-dpdt-2a-mini-relay/1.html

They have been working fine for 20 years.

Carl.

On 6/28/2020 5:05 PM, Bob Macionis wrote:

Thanks Carl/.  I’m not very knowledgeable about relays, but it seems to be a good answer.  Any particular characteristics of the relay I should look for?   My BD 20 block detectors have an output for a relay.

Bob

 

Sent from Mail for Windows 10

 

From: Carl
Sent: Sunday, June 28, 2020 3:18 PM
To: w4dccqa@groups.io
Subject: Re: [w4dccqa] polarity reversing & block occupancy detector

 

Hi Bob:

You could use the output to run a DPDT relay.

Carl.

On 6/28/2020 1:38 PM, Bob Macionis wrote:

I have lower quadrant semaphores controlled by tortoise machines.  I want the blades to move automatically when the block protected by the semaphores is occupied/unoccupied.   Is there an occupancy detector that reverses polarity of its output that would cause the tortoises to throw? Or maybe there is another way to auto throw the tortoises when a train enters/leaves the block?  Thanks for your advice.
Bob Macionis

 


Re: polarity reversing & block occupancy detector

Bob Macionis
 

Thanks Carl/.  I’m not very knowledgeable about relays, but it seems to be a good answer.  Any particular characteristics of the relay I should look for?   My BD 20 block detectors have an output for a relay.

Bob

 

Sent from Mail for Windows 10

 

From: Carl
Sent: Sunday, June 28, 2020 3:18 PM
To: w4dccqa@groups.io
Subject: Re: [w4dccqa] polarity reversing & block occupancy detector

 

Hi Bob:

You could use the output to run a DPDT relay.

Carl.

On 6/28/2020 1:38 PM, Bob Macionis wrote:

I have lower quadrant semaphores controlled by tortoise machines.  I want the blades to move automatically when the block protected by the semaphores is occupied/unoccupied.   Is there an occupancy detector that reverses polarity of its output that would cause the tortoises to throw? Or maybe there is another way to auto throw the tortoises when a train enters/leaves the block?  Thanks for your advice.
Bob Macionis

 


Re: Bi-Polar Red /Green LEDs in Control Panels.

Warren Smith
 


afternoon Everyone:

        I have been using bicolor LEDS with tortoise motors.  I using the secondary switches on the tortoise to control the LEDS.  I do use a separate 5v power supply  and a 220 ohm resistor on the ground leg (using three legged LED's).  This way I can do maintenance on the motors (also have their own power supply) and LEDs without having power to the track.  Hope this helps a little.

Warren

On Sun, Jun 28, 2020 at 1:20 PM Carl <carl.blum@...> wrote:

Hi Tom:

My first thought was to use two power supplies, one for Red and one for Green.

The different resistors is a good idea too. Do you have a resistor decade box to try different values?

Carl.

On 6/28/2020 12:49 PM, Paul O wrote:
Tom, I believe you have two options;
#1, an extra dropping resistor in series with the brighter color, or #2, LEDs from a different source.

Paul O


Re: Bi-Polar Red /Green LEDs in Control Panels.

Carl
 

Hi Tom:

My first thought was to use two power supplies, one for Red and one for Green.

The different resistors is a good idea too. Do you have a resistor decade box to try different values?

Carl.

On 6/28/2020 12:49 PM, Paul O wrote:
Tom, I believe you have two options;
#1, an extra dropping resistor in series with the brighter color, or #2, LEDs from a different source.

Paul O

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