Date   
Am I creating a reversing loop in my yard?

rpeter4780 <rpeter4780@...>
 

I am posting a track diagram of a yard track I am building. In Roypea, yard track.jpg. The Blue track in the picture is the area I am concerned with (right now). I've built a buzzer with a 9v battery and I have isolated an apparent short in that blue section. Continuity tests with my meter do not reveal any issues (?)

This is HO scale, code 100 track, and all but the double crossover is Peco insulfrog turnouts. I will be installing a Digitrak Zephyr. Turnout control is with Caboose ground throws. It is also a shelf layout in a 5'3"x19'3" room. The mainline track at left begins its curve to the left just past the edge of the image. Off the right is where a 7 track hump yard and a two track RIP track will be done in phase 2, all of these are stub ended tracks. The blue track in question is issolated on both rails at all connections to the other blocks. Portions of the other blocks will be shut down with DPDT swithces, MOW for example. And yes those are three double slip switches, forgive me.

My question relates primarily to the three red circles, but any other issues spotted will be apprecaited. I know this is a busy area but it fits my space and needs, I'd rather have track than scenery apparantly.

Electronics is not my strongest suit, and so my questions:
1) Am I introducing one or more reversing sections of track with the crossovers in the red circles.
2) Should I isolate the diverging/crossover routes of the insulfrog turnouts that make up the crossovers?
3) Are auto-reversing unit(s) called for here, where would they be placed?

Im sure there are other questions I should be asking if I knew what I was talking about, so feel free to point them out.

Thanks for any assistance offered. Hope this is not too dumb a question or TMI.

Roypea

Re: Resistors - Wattage

Vollrath, Don <dvollrath@...>
 

And even with the added reverse protection diode - Assuming ~1 volt drop across the LED, and that the 18V is actually AC & not rectified to DC. 1/2 wave current through the LED will be (18-1)v/470 ohms = 0.036 or 36 ma. Time averaged curent will be 18 ma. With 470 ohms resistor limiting current it will see 1/2 x 0.036 x 0.036 x 470 ohms = 0.30 watts. The LED will be bright and you need a 1/2 watt resistor.
If the 18Vac is full-wave rectified DC - Average current through the LED and resistor will be the full 38 ma. The LED will be super bright but won't last long. Resistor watts will be 0.61 watts. Bump the resistor ohms up to 1,000 ohms. LED current will drop to ~17 ma. Resistor dissipation will be 17 x 17 x 1k = 0.29 Watts. Need a 1/2 watt resistor.
DonV

-----Original Message-----
From: WiringForDCC@... [mailto:WiringForDCC@...] On Behalf Of hacketet
Sent: Tuesday, September 01, 2009 8:18 AM
To: WiringForDCC@...
Subject: [WiringForDCC] Re: Resistors - Wattage

I re read your note. If you have already wired things up and they are working OK, ignore the following.

If you power an LED directly from a DCC power supply, it will be subjected to 18 V reverse voltage. LEDs are diodes, but they are not designed to withstand large reverse voltages and may well get fried. Their breakdown voltages are seldom if ever published because they aren't supposed to see them. The same is true if the transformer produces 18 VAC. In either case you might want to put a regular diode like a 1N4004 in line with the LED to block the reverse voltage.

--- In WiringForDCC@..., "richhotrain" <redking56@...> wrote:

Some of my LEDs are powered off of an 18 volt transformer (Railpower 1370) and others are powered directly off of the DCC power system (NCE PH-Pro 5 amp).

When using limiting resistors on the LEDs, does it make any difference if a 1/4 watt or 1/2 watt resistor of the same ohms (e.g., 470 ohms) is selected?

Thanks.

Rich



------------------------------------

http://www.WiringForDCC.comYahoo! Groups Links

Re: Resistors - Wattage

hacketet <hacketet@...>
 

I re read your note. If you have already wired things up and they are working OK, ignore the following.

If you power an LED directly from a DCC power supply, it will be subjected to 18 V reverse voltage. LEDs are diodes, but they are not designed to withstand large reverse voltages and may well get fried. Their breakdown voltages are seldom if ever published because they aren't supposed to see them. The same is true if the transformer produces 18 VAC. In either case you might want to put a regular diode like a 1N4004 in line with the LED to block the reverse voltage.

--- In WiringForDCC@..., "richhotrain" <redking56@...> wrote:

Some of my LEDs are powered off of an 18 volt transformer (Railpower 1370) and others are powered directly off of the DCC power system (NCE PH-Pro 5 amp).

When using limiting resistors on the LEDs, does it make any difference if a 1/4 watt or 1/2 watt resistor of the same ohms (e.g., 470 ohms) is selected?

Thanks.

Rich

Re: Resistors - Wattage

hacketet <hacketet@...>
 

The resistor should have a minimum wattage of V*V/R (or E*E/R for you physicists out there). For example, if the supply is 12 V and the resistor is 400 ohms (so I don't have to reach for a calculator)

W=12*12/400 = 144/400 = 0.36

In this case you would go to the next higher wattage rating and select a 1/2 W resistor.

--- In WiringForDCC@..., "richhotrain" <redking56@...> wrote:

Some of my LEDs are powered off of an 18 volt transformer (Railpower 1370) and others are powered directly off of the DCC power system (NCE PH-Pro 5 amp).

When using limiting resistors on the LEDs, does it make any difference if a 1/4 watt or 1/2 watt resistor of the same ohms (e.g., 470 ohms) is selected?

Thanks.

Rich

Re: Resistors - Wattage

dougstuard <dstuard@...>
 

Based on Ohm's Law, the power dissipated by a resistor is the resistance in Ohms times the square of the current in Amps. Assuming a maximum current of .02 Amps (20 ma) for the LED, a 470 Ohm resistor would need to dissipate 470 * (.02)^2 = 470* .0004 = .188 Watts. Thus you could use any wattage resistor of 1/4 watt or more, space permitting...it's the Ohms that matter.

Doug Stuard

--- In WiringForDCC@..., "richhotrain" <redking56@> wrote:

Some of my LEDs are powered off of an 18 volt transformer (Railpower 1370) and others are powered directly off of the DCC power system (NCE PH-Pro 5 amp).

When using limiting resistors on the LEDs, does it make any difference if a 1/4 watt or 1/2 watt resistor of the same ohms (e.g., 470 ohms) is selected?

Thanks.

Rich

Resistors - Wattage

richhotrain <redking56@...>
 

Some of my LEDs are powered off of an 18 volt transformer (Railpower 1370) and others are powered directly off of the DCC power system (NCE PH-Pro 5 amp).

When using limiting resistors on the LEDs, does it make any difference if a 1/4 watt or 1/2 watt resistor of the same ohms (e.g., 470 ohms) is selected?

Thanks.

Rich

Re: Wiring LEDs to a DPST Switch

richhotrain <redking56@...>
 

--- In WiringForDCC@..., "Vollrath, Don" <dvollrath@...> wrote:

Sounds like you have connected the ammeter across the DCC bus, which makes the booster trip. Connect both INPUT leads of the RRampMeter to the booster DCC bus with the the current measuring lead on the wire that is going to the track power switch in my diagram. Connect the OUTPUT current measuring wire of the RRampMeter to the other side of that same switch pole. You should be able to measure track voltage in either case, but can measure current only when the switch is open/off. The LEDs will be operated by the other switch pole.
Don,

I will give that a try.

I do want to thank you for all of your time and help on the LED lighting issue. Your wiring diagram does work quite effectively. I actually found an on-line electronics supply store that carries a TPST switch. I didn't know such an animal existed. That would solve both of my problems.

My other alternative is to abandon the red/green LED idea and just install two green LEDs, one always on to indicate DCC power status and the other on only when the DPST switch is flipped ON to indicate that the RRampMeter is bypassed.

Rich

Re: Wiring LEDs to a DPST Switch

Vollrath, Don <dvollrath@...>
 

Sounds like you have connected the ammeter across the DCC bus, which makes the booster trip. Connect both INPUT leads of the RRampMeter to the booster DCC bus with the the current measuring lead on the wire that is going to the track power switch in my diagram. Connect the OUTPUT current measuring wire of the RRampMeter to the other side of that same switch pole. You should be able to measure track voltage in either case, but can measure current only when the switch is open/off. The LEDs will be operated by the other switch pole.

-----Original Message-----
From: WiringForDCC@... [mailto:WiringForDCC@...] On Behalf Of richhotrain
Sent: Monday, August 31, 2009 2:56 PM
To: WiringForDCC@...
Subject: [WiringForDCC] Re: Wiring LEDs to a DPST Switch

--- In WiringForDCC@..., "Vollrath, Don" <dvollrath@...> wrote:

Rich,
1. I don't have one these gadgets to analyze, but looking at the pics at http://www.tonystrains.com/gallery/rrampmeter/rrampmetercloseup.htm ...You can verify what I say below by tracing the copper connections from end to end of the RRampMeter circuit board. One of them (I say the larger copper pad w/ red connectors for Series 3) flows from one end to the other without being interrupted. The other flows through rectifier parts mounted near the bottom of the PCB. This is the booster-track lead that gets measured for current.
2. To measure current you only need to interrupt ONE DCC bus wire
between booster and track. From the pics it looks like the smaller
copper pad (black test lead wire) on either end of the RRampMeter contains the parts that monitor current. Therefore those power connections, one from each end of the RRampMeter go to one side of the DPST switch. (current through the switch bypasses the RRampMeter when On.) 3. To measure voltage the RRampMeter needs to additionally have one of the other (longer) copper pads or red lead wire connection go to the other (unbroken) DCC bus wire from the booster. This DCC bus wire also goes directly to track (not through the switch) 4. You can continue to use clip lead connections so that your meter is portable. Clip the black leads to the switch (one on each side of one of the NO switch poles. Clip the red lead to the other DCC bus wire.
5. That leaves the other side of the DPST switch to be connected as I show to operate the LEDs.
6. If my assumptions about red & black leads is wrong simply interchange red & black RRampMeter connections.

DonV
Apparently, the RRampMeter will only read voltage unless both cables are connected in series. Otherwise, it won't measure current. If the voltage clips are connected to one pole of the DPST and one amp clip is attached to the unbroken bus wire, the system shorts.

Nuts, so I am back to my original issue of trying to wire LEDs when both poles of a DPST are in use so that the red LED goes off when the green LED goes on.

Rich



------------------------------------

http://www.WiringForDCC.comYahoo! Groups Links

Re: Wiring LEDs to a DPST Switch

richhotrain <redking56@...>
 

--- In WiringForDCC@..., "Vollrath, Don" <dvollrath@...> wrote:

Rich,
1. I don't have one these gadgets to analyze, but looking at the pics at http://www.tonystrains.com/gallery/rrampmeter/rrampmetercloseup.htm ...You can verify what I say below by tracing the copper connections from end to end of the RRampMeter circuit board. One of them (I say the larger copper pad w/ red connectors for Series 3) flows from one end to the other without being interrupted. The other flows through rectifier parts mounted near the bottom of the PCB. This is the booster-track lead that gets measured for current.
2. To measure current you only need to interrupt ONE DCC bus wire between booster and track. From the pics it looks like the smaller copper pad (black test lead wire) on either end of the RRampMeter contains the parts that monitor current. Therefore those power connections, one from each end of the RRampMeter go to one side of the DPST switch. (current through the switch bypasses the RRampMeter when On.)
3. To measure voltage the RRampMeter needs to additionally have one of the other (longer) copper pads or red lead wire connection go to the other (unbroken) DCC bus wire from the booster. This DCC bus wire also goes directly to track (not through the switch)
4. You can continue to use clip lead connections so that your meter is portable. Clip the black leads to the switch (one on each side of one of the NO switch poles. Clip the red lead to the other DCC bus wire.
5. That leaves the other side of the DPST switch to be connected as I show to operate the LEDs.
6. If my assumptions about red & black leads is wrong simply interchange red & black RRampMeter connections.

DonV
Apparently, the RRampMeter will only read voltage unless both cables are connected in series. Otherwise, it won't measure current. If the voltage clips are connected to one pole of the DPST and one amp clip is attached to the unbroken bus wire, the system shorts.

Nuts, so I am back to my original issue of trying to wire LEDs when both poles of a DPST are in use so that the red LED goes off when the green LED goes on.

Rich

Re: Wiring LEDs to a DPST Switch

Vollrath, Don <dvollrath@...>
 

Rich,
1. I don't have one these gadgets to analyze, but looking at the pics at http://www.tonystrains.com/gallery/rrampmeter/rrampmetercloseup.htm ...You can verify what I say below by tracing the copper connections from end to end of the RRampMeter circuit board. One of them (I say the larger copper pad w/ red connectors for Series 3) flows from one end to the other without being interrupted. The other flows through rectifier parts mounted near the bottom of the PCB. This is the booster-track lead that gets measured for current.
2. To measure current you only need to interrupt ONE DCC bus wire between booster and track. From the pics it looks like the smaller copper pad (black test lead wire) on either end of the RRampMeter contains the parts that monitor current. Therefore those power connections, one from each end of the RRampMeter go to one side of the DPST switch. (current through the switch bypasses the RRampMeter when On.)
3. To measure voltage the RRampMeter needs to additionally have one of the other (longer) copper pads or red lead wire connection go to the other (unbroken) DCC bus wire from the booster. This DCC bus wire also goes directly to track (not through the switch)
4. You can continue to use clip lead connections so that your meter is portable. Clip the black leads to the switch (one on each side of one of the NO switch poles. Clip the red lead to the other DCC bus wire.
5. That leaves the other side of the DPST switch to be connected as I show to operate the LEDs.
6. If my assumptions about red & black leads is wrong simply interchange red & black RRampMeter connections.

DonV

-----Original Message-----
From: WiringForDCC@... [mailto:WiringForDCC@...] On Behalf Of richhotrain
Sent: Monday, August 31, 2009 10:19 AM
To: WiringForDCC@...
Subject: [WiringForDCC] Re: Wiring LEDs to a DPST Switch

--- In WiringForDCC@..., "Vollrath, Don" <dvollrath@...> wrote:

Yes, But look again at my drawing. Move the resistor(s) so that power for either green or red led flows through the same resistor. In my circuit when you close the switch the lower voltage drop on the green led diverts all current through the single resistor away from the red led (and the extra diodes in that path) to light up the green one.
You don't need to break both DCC feed wires to the track to measure current with the RRampMater or any other ammeter. Yes there are 3 connections to the RRampMeter... So connect the two carying ammeter current to the power pole of the switch and simply clip the 'voltage' supply wire of the RRampMeter to the other DCC bus wire (the one unbroken by the switch).
DonV
Success !

Sorry, Don, I should have looked closer at your drawing in the first place. The LED lighting now works as you indicated.

As to the RRampMeter, when I first bought it a few years ago, I incorrectly wired it by simply tapping into the two bus wires with the alligator clips. When I was informed that the current needed to run through the RRampMeter to accurately measure current, I broke both bus wires and placed the alligator clips on either side of each bus wire so that current ran through the RRampMeter.

My RRampMeter is Version III which encloses the meter in a plastic case. If I want to continue to use the two-cable connectors with the alligator clips on the ends of the cables, how do I complete the connections? Can I attach the alligator clips to NC and NO sides of the pole of the DPST switch for the interrupted bus wire and simply attach the other two alligator clips to the uninterrupted bus wire?

Rich



------------------------------------

http://www.WiringForDCC.comYahoo! Groups Links

Re: Wiring LEDs to a DPST Switch

richhotrain <redking56@...>
 

--- In WiringForDCC@..., "Vollrath, Don" <dvollrath@...> wrote:

Yes, But look again at my drawing. Move the resistor(s) so that power for either green or red led flows through the same resistor. In my circuit when you close the switch the lower voltage drop on the green led diverts all current through the single resistor away from the red led (and the extra diodes in that path) to light up the green one.
You don't need to break both DCC feed wires to the track to measure current with the RRampMater or any other ammeter. Yes there are 3 connections to the RRampMeter... So connect the two carying ammeter current to the power pole of the switch and simply clip the 'voltage' supply wire of the RRampMeter to the other DCC bus wire (the one unbroken by the switch).
DonV
Success !

Sorry, Don, I should have looked closer at your drawing in the first place. The LED lighting now works as you indicated.

As to the RRampMeter, when I first bought it a few years ago, I incorrectly wired it by simply tapping into the two bus wires with the alligator clips. When I was informed that the current needed to run through the RRampMeter to accurately measure current, I broke both bus wires and placed the alligator clips on either side of each bus wire so that current ran through the RRampMeter.

My RRampMeter is Version III which encloses the meter in a plastic case. If I want to continue to use the two-cable connectors with the alligator clips on the ends of the cables, how do I complete the connections? Can I attach the alligator clips to NC and NO sides of the pole of the DPST switch for the interrupted bus wire and simply attach the other two alligator clips to the uninterrupted bus wire?

Rich

Re: Wiring LEDs to a DPST Switch

Vollrath, Don <dvollrath@...>
 

Yes, But look again at my drawing. Move the resistor(s) so that power for either green or red led flows through the same resistor. In my circuit when you close the switch the lower voltage drop on the green led diverts all current through the single resistor away from the red led (and the extra diodes in that path) to light up the green one.
You don't need to break both DCC feed wires to the track to measure current with the RRampMater or any other ammeter. Yes there are 3 connections to the RRampMeter... So connect the two carying ammeter current to the power pole of the switch and simply clip the 'voltage' supply wire of the RRampMeter to the other DCC bus wire (the one unbroken by the switch).
DonV

-----Original Message-----
From: WiringForDCC@... [mailto:WiringForDCC@...] On Behalf Of richhotrain
Sent: Sunday, August 30, 2009 4:30 PM
To: WiringForDCC@...
Subject: [WiringForDCC] Re: Wiring LEDs to a DPST Switch

--- In WiringForDCC@..., "richhotrain" <redking56@...> wrote:

--- In WiringForDCC@..., "Vollrath, Don" <dvollrath@> wrote:

My mistake Rich.
For the RED LED, the cathode of the diode connects to the LED and the anode connects to the resistor and switch terminal. It is backwards in my description. But I think you have the resistor on the wrong side of the switch. It must be in the path to restrict current through both LEDs. It sounds like you are also trying to get them powered from DCC track power... Right? If so, there should be yet another diode to protect the LEDs from reverse voltage. I've put a connection drawing (worth a thousand words) in the files section. Look for RRampmeter LEDs.pdf Aug 29. It shows 2 diodes in series with the Red LED, just in case you have a high V green and low V red LED.
The Green LED will be on when it is safe to remove the RRrampmeter. Red when you are using it.
DonV
Don,
In my previous response, I misstated my wiring by incorrectly stating which side of the switch was wired. So, let me restate the entire response.

I reversed the direction of the two diodes as you directed and now the red LED lights up with the DPST switch in the OFF position. When the switch is turned ON, the green LED lights up but the red LED stays on as well.

As I reviewed your drawing in the Files section, it reminded me of a question that you initially asked and I failed to respond to. Your drawing shows the RRampMeter connected to only one bus wire. However, I have set up the RRampMeter as a Panel Meter per the RRampMeter Application Notes to monitor the power supplied to the layout.

The two bus wires from the command station connect to one side of the DPST switch and the two bus wires leading to the track connect to the other side of the DPST switch. The RRampMeter is mounted on a panel and the alligator clips connect to the bus wires on either side of the DPST switch. With the DPST switch in the OFF position, current flows through the RRampMeter to the track. If the RRampMeter is removed from the panel to measure track voltage, the DPST switch is thrown to the ON position to provide power from the command station to the track.

Here is my wiring arrangement for the LEDs. The cathode side of each LED is soldered together and wired to the NC side of one switch pole (holding one bus wire from the command station). On the NO side of that same switch pole, a resistor is connected and wired to the green LED. On the NC side of the opposite pole, the Red LED is wired with a resistor coming off the switch followed in series by two diodes with cathode side facing the red LED.

As I study my own drawing of how I wired this arrangement, I can see why the red LED is always lit. Is there a way to keep this basic arrangement and have the red LED turn off when the DPST switch is flipped ON ?

Sorry for all of the trouble this is causing.

Rich



------------------------------------

http://www.WiringForDCC.comYahoo! Groups Links

Re: Arnold Rapido Turnouts

wirefordcc <wire4dcc@...>
 

--- In WiringForDCC@..., Tiago <tiago.matias@...> wrote:

Hello,

I have a lot of old Arnold Rapido turnouts, 3-wired, solenoid based that I
got from my father. I'm thinking on building a DCC layout and I'm currently
Tiago,

Your turnouts should work with either AC or DC. You don't have to control your turnouts with DCC controllers to use the turnouts on DCC layouts. You can just power them as you always would have. If you want to control them with DCC controllers, I think your turnouts should work fine with any DCC stationary or auxillary controller designed to operate twin coil switch machines.

The bigger question is whether the turnout is DCC friendly. Since I am not familiar Arnold Rapido turnouts, I can't answer that question. If the Rapido turnouts are not DCC friendly, you may find that you have shorts that shutdown your railroad. To determine if your turnouts are DCC friendly, check out my website at:

http://www.wiringfordcc.com/switches.htm#a1

If you will be the sole operator on your railroad, DCC friendly turnouts may not be a big issue for you.

There isn't enough information for me to tell if you can control your turntable with DCC. I suspect it cannot be done easily, if at all. But again, is your goal to control the turntable with DCC or to simply run DCC trains on it? If you simply want to run DCC trains on it, I suspect your turntable will work just fine. Just use an auto reversing unit to power the turntable bridge. See my website at:

http://www.wiringfordcc.com/track_2.htm#a44

Allan



investigating how much of this material is DCC-capable.

Are these types of turnouts controlable with modern decoders? I remember
that these turnouts operated with 16v AC and the circuit remained "opened"
because they worked great with the turnout buttons that Arnold made that had
little lamps inside indicating the current status of the turnout.

I also have a roundhouse. Is this DCC controlable ?

thanks for your help. I still have to make an inventory of the locos to see
if they are DCC-cabable (in terms of space, at least)


Many thanks,

Tiago Matias,


------------------------------------------
Reference for the turnouts:
http://www.guidetozscale.com/general/Arnold_Rapido/Technic/Track_Switches/track_switches.html

For the roundhouse:
http://www.scalerailsonline.com/topic.asp?TOPIC_ID=2817 (I have this
controller and another one, they made after, with only "next" and "previous"
buttons)
------------------------------------------


[Non-text portions of this message have been removed]

Re: Wiring LEDs to a DPST Switch

richhotrain <redking56@...>
 

--- In WiringForDCC@..., "richhotrain" <redking56@...> wrote:

--- In WiringForDCC@..., "Vollrath, Don" <dvollrath@> wrote:

My mistake Rich.
For the RED LED, the cathode of the diode connects to the LED and the anode connects to the resistor and switch terminal. It is backwards in my description. But I think you have the resistor on the wrong side of the switch. It must be in the path to restrict current through both LEDs. It sounds like you are also trying to get them powered from DCC track power... Right? If so, there should be yet another diode to protect the LEDs from reverse voltage. I've put a connection drawing (worth a thousand words) in the files section. Look for RRampmeter LEDs.pdf Aug 29. It shows 2 diodes in series with the Red LED, just in case you have a high V green and low V red LED.
The Green LED will be on when it is safe to remove the RRrampmeter. Red when you are using it.
DonV
Don,
In my previous response, I misstated my wiring by incorrectly stating which side of the switch was wired. So, let me restate the entire response.

I reversed the direction of the two diodes as you directed and now the red LED lights up with the DPST switch in the OFF position. When the switch is turned ON, the green LED lights up but the red LED stays on as well.

As I reviewed your drawing in the Files section, it reminded me of a question that you initially asked and I failed to respond to. Your drawing shows the RRampMeter connected to only one bus wire. However, I have set up the RRampMeter as a Panel Meter per the RRampMeter Application Notes to monitor the power supplied to the layout.

The two bus wires from the command station connect to one side of the DPST switch and the two bus wires leading to the track connect to the other side of the DPST switch. The RRampMeter is mounted on a panel and the alligator clips connect to the bus wires on either side of the DPST switch. With the DPST switch in the OFF position, current flows through the RRampMeter to the track. If the RRampMeter is removed from the panel to measure track voltage, the DPST switch is thrown to the ON position to provide power from the command station to the track.

Here is my wiring arrangement for the LEDs. The cathode side of each LED is soldered together and wired to the NC side of one switch pole (holding one bus wire from the command station). On the NO side of that same switch pole, a resistor is connected and wired to the green LED. On the NC side of the opposite pole, the Red LED is wired with a resistor coming off the switch followed in series by two diodes with cathode side facing the red LED.

As I study my own drawing of how I wired this arrangement, I can see why the red LED is always lit. Is there a way to keep this basic arrangement and have the red LED turn off when the DPST switch is flipped ON ?

Sorry for all of the trouble this is causing.

Rich

Re: Velcro & Cable Ties

wirefordcc <wire4dcc@...>
 

Velcro sounds like one good way to hold your wiring neatly under your layout. For those who can't get the velcro, here's another idea: Releaseable (reusable, unlockable) cable ties. Visit my website in the Parts section and scroll down to "Cable Ties and Accessories" at:

http://www.wiringfordcc.com/parts.htm

You can get these from Mouser Electronics. They come in a variety of lengths. Use a screw and a mounting block (listed with the cable ties on my website) to hold the wiring under your layout.

Allan

Re: Wiring LEDs to a DPST Switch

richhotrain <redking56@...>
 

--- In WiringForDCC@..., "Vollrath, Don" <dvollrath@...> wrote:

My mistake Rich.
For the RED LED, the cathode of the diode connects to the LED and the anode connects to the resistor and switch terminal. It is backwards in my description. But I think you have the resistor on the wrong side of the switch. It must be in the path to restrict current through both LEDs. It sounds like you are also trying to get them powered from DCC track power... Right? If so, there should be yet another diode to protect the LEDs from reverse voltage. I've put a connection drawing (worth a thousand words) in the files section. Look for RRampmeter LEDs.pdf Aug 29. It shows 2 diodes in series with the Red LED, just in case you have a high V green and low V red LED.
The Green LED will be on when it is safe to remove the RRrampmeter. Red when you are using it.
DonV
Don,

I reversed the direction of the two diodes and now the red LED lights with the DPST switch in the OFF position. When the switch is turned ON, the green LED lights up but the red LED stays on as well. But here is why that happens.

As I reviewed your drawing in the Files section, it reminded me of a question that you initially asked and I failed to respond to. Your drawing shows the RRampMeter connected to only one bus wire. However, I have set up the RRampMeter as a Panel Meter per the RRampMeter Application Notes to monitor the power supplied to the layout.

The two bus wires from the command station connect to one side of the DPST switch and the two bus wires leading to the track connect to the other side of the DPST switch. The RRampMeter is mounted on a panel and the alligator clips connect to the bus wires on either side of the DPST switch. With the DPST switch in the OFF position, current flows through the RRampMeter to the track. If the RRampMeter is removed from the panel to measure track voltage, the DPST switch is thrown to the ON position to provide power from the command station to the track.

Here is my wiring arrangement for the LEDs. The cathode side of each LED is soldered together and wired to the NO side of one switch pole (holding one bus wire from the command station). On the NC side of that same switch pole, a resistor is connected and wired to the green LED. On the NO side of the opposite pole, the Red LED is wired with a resistor coming off the switch followed in series by two diodes with cathode side facing the red LED.

As I study my own drawing of how I wired this arrangement, I can see why the red LED is always lit. Is there a way to keep this basic arrangement and have the red LED turn off when the DPST switch is flipped ON ?

Sorry for all of the trouble this is causing.

Rich

Re: Velcro (was Building DCC in stages II)

Glenn
 

These are not the typical Velcro stuff. The strips have hooks on one side
and loops on the other.

The tool holder garden/hardware variety is the same, but mine are smaller
and cheaper. They come in a continuous roll with perforations and actually
are cheaper than the regular Velcro. $6 will get you 33 feet!

Glenn

-----Original Message-----
From: WiringForDCC@... [mailto:WiringForDCC@...] On
Behalf Of Richard Sutcliffe
Sent: Saturday, August 29, 2009 1:29
To: WiringForDCC@...
Subject: Re: [WiringForDCC] Velcro (was Building DCC in stages II)

Glen

Check with your local fabric supplier, they should have Velcro by the
metre in several widths.
Garden suppliers have the double side by the roll to tie up plants.
Hardware stores have the double sided for temporary tool holders or
other place where a temporary strap is needed.
You don't need the ones made specifically wire hanging and the added
expense for a specialized item.
Richard A. Sutcliffe
General Manager
Bradley, Roger, & Tidewater Rwy. Co.
Cariboo Traction Co.


From: scaletone@...
Subject: Re: [WiringForDCC] Building DCC in stages II
Date: August 28, 2009 5:15:00 PM PDT
To: WiringForDCC@...
Reply-To: WiringForDCC@...

Hi Glen,

what is the item number of the velcro I will need to order over the
net as I am in australia if I can not find them here

Regards

Anthony James






------------------------------------

http://www.WiringForDCC.comYahoo! Groups Links

Re: Wiring LEDs to a DPST Switch

Vollrath, Don <dvollrath@...>
 

My mistake Rich.
For the RED LED, the cathode of the diode connects to the LED and the anode connects to the resistor and switch terminal. It is backwards in my description. But I think you have the resistor on the wrong side of the switch. It must be in the path to restrict current through both LEDs. It sounds like you are also trying to get them powered from DCC track power... Right? If so, there should be yet another diode to protect the LEDs from reverse voltage. I've put a connection drawing (worth a thousand words) in the files section. Look for RRampmeter LEDs.pdf Aug 29. It shows 2 diodes in series with the Red LED, just in case you have a high V green and low V red LED.
The Green LED will be on when it is safe to remove the RRrampmeter. Red when you are using it.
DonV

-----Original Message-----
From: WiringForDCC@... [mailto:WiringForDCC@...] On Behalf Of richhotrain
Sent: Saturday, August 29, 2009 9:40 AM
To: WiringForDCC@...
Subject: [WiringForDCC] Re: Wiring LEDs to a DPST Switch

--- In WiringForDCC@..., "richhotrain" <redking56@...> wrote:

--- In WiringForDCC@..., "Vollrath, Don" <dvollrath@> wrote:

Yes. But, does the switch need to do anything else besides control the LEDs?
If no, one way is to use two resistor fed circuits. One turns the Green On via the switch, while the other pole shorts out the Red LED turning it Off. Wire one lead of both resistors to a + voltage supply source and the other ends to the 'wiper' of the separate Double Pole switch sections. Wire the cathodes of the LEDs (point of the arrow symbol) together and to the negative supply lead. The anode of the Green LED lead goes to the Normally Open side of one of the switch poles. [turning the Green LED On when the sw is turned On.] The anode of the Red LED goes to the feed, or resistor side, of the other switch pole. The N.O. side of that sw pole goes to the common cathodes and (-) supply.

Can also be done using only one pole of the switch. Connect the cathodes of the two LEDs together and to the (-) supply. Connect a resistor to the feed of a SPST switch. Connect the anode of the green LED to the N.O. switch pole. [when the sw is closed the Grn LED will be ON.] Connect a diode (maybe 2) in series with the Red LED (arrows pointing in the same direction). (1N4148 or any 1N4xxx) Connect the cathode of the diode (string?) to the resistor/sw terminal. With the sw Off, no power to the Grn LED, but the Red one will be lighted. With the sw On, the Grn LED will be lighted, but the voltage drop across it will be limited to less than it takes to overcome the voltage drops of the Red LED + diode(s)... So Red will be Off.
Don,

I tried the second method that you suggested, but I must be misunderstanding your instructions because the LEDs are not lighting.

I soldered the cathode legs of the red and green LEDs together and wired them to the negative side of a transformer. Then, I soldered the anode leg of the red LED to the anode side of a diode and the cathode side of the diode to a 470 ohm resistor. So far, so good?

At that point, does the anode leg of the green LED connect to one of the DPST switch leads on the ON side where the bus wire is connected to the rail, and does the resistored leg of the red LED connect on the OFF side of the DPST switch where the bus wire is connected from the command station?

That's how I connected it but no luck. Obviously, I am doing something wrong.

Rich
Don,

Over night, I had a chance to review my wiring and to review my prior message on this thread.

Here is the current status of my efforts. I can get the green LED to light when the switch is turned on, but I get no light from the red LED at any time.

I wired the circuit as follows: The cathode side of both LEDs are soldered together and wired to the (-) supply. The anode side of the green LED is wired to the NO switch pole with a resistor wired between the LED and the NO switch pole. The anode side of the red LED is wired to the NC switch pole. Between the Red LED and the resistor on the NC switch pole side, I wired in a 1N4xxx diode with the cathode side facing the resistor.

What am I doing wrong? Incidentally, I double checked the red LED and it is operative (not burned out).

Rich



------------------------------------

http://www.WiringForDCC.comYahoo! Groups Links

Re: Wiring LEDs to a DPST Switch

richhotrain <redking56@...>
 

--- In WiringForDCC@..., "richhotrain" <redking56@...> wrote:

--- In WiringForDCC@..., "Vollrath, Don" <dvollrath@> wrote:

Yes. But, does the switch need to do anything else besides control the LEDs?
If no, one way is to use two resistor fed circuits. One turns the Green On via the switch, while the other pole shorts out the Red LED turning it Off. Wire one lead of both resistors to a + voltage supply source and the other ends to the 'wiper' of the separate Double Pole switch sections. Wire the cathodes of the LEDs (point of the arrow symbol) together and to the negative supply lead. The anode of the Green LED lead goes to the Normally Open side of one of the switch poles. [turning the Green LED On when the sw is turned On.] The anode of the Red LED goes to the feed, or resistor side, of the other switch pole. The N.O. side of that sw pole goes to the common cathodes and (-) supply.

Can also be done using only one pole of the switch. Connect the cathodes of the two LEDs together and to the (-) supply. Connect a resistor to the feed of a SPST switch. Connect the anode of the green LED to the N.O. switch pole. [when the sw is closed the Grn LED will be ON.] Connect a diode (maybe 2) in series with the Red LED (arrows pointing in the same direction). (1N4148 or any 1N4xxx) Connect the cathode of the diode (string?) to the resistor/sw terminal. With the sw Off, no power to the Grn LED, but the Red one will be lighted. With the sw On, the Grn LED will be lighted, but the voltage drop across it will be limited to less than it takes to overcome the voltage drops of the Red LED + diode(s)... So Red will be Off.
Don,

I tried the second method that you suggested, but I must be misunderstanding your instructions because the LEDs are not lighting.

I soldered the cathode legs of the red and green LEDs together and wired them to the negative side of a transformer. Then, I soldered the anode leg of the red LED to the anode side of a diode and the cathode side of the diode to a 470 ohm resistor. So far, so good?

At that point, does the anode leg of the green LED connect to one of the DPST switch leads on the ON side where the bus wire is connected to the rail, and does the resistored leg of the red LED connect on the OFF side of the DPST switch where the bus wire is connected from the command station?

That's how I connected it but no luck. Obviously, I am doing something wrong.

Rich
Don,

Over night, I had a chance to review my wiring and to review my prior message on this thread.

Here is the current status of my efforts. I can get the green LED to light when the switch is turned on, but I get no light from the red LED at any time.

I wired the circuit as follows: The cathode side of both LEDs are soldered together and wired to the (-) supply. The anode side of the green LED is wired to the NO switch pole with a resistor wired between the LED and the NO switch pole. The anode side of the red LED is wired to the NC switch pole. Between the Red LED and the resistor on the NC switch pole side, I wired in a 1N4xxx diode with the cathode side facing the resistor.

What am I doing wrong? Incidentally, I double checked the red LED and it is operative (not burned out).

Rich

Re: Velcro (was Building DCC in stages II)

Richard Sutcliffe
 

Glen

Check with your local fabric supplier, they should have Velcro by the
metre in several widths.
Garden suppliers have the double side by the roll to tie up plants.
Hardware stores have the double sided for temporary tool holders or
other place where a temporary strap is needed.
You don't need the ones made specifically wire hanging and the added
expense for a specialized item.
Richard A. Sutcliffe
General Manager
Bradley, Roger, & Tidewater Rwy. Co.
Cariboo Traction Co.

From: scaletone@...
Subject: Re: [WiringForDCC] Building DCC in stages II
Date: August 28, 2009 5:15:00 PM PDT
To: WiringForDCC@...
Reply-To: WiringForDCC@...

Hi Glen,

what is the item number of the velcro I will need to order over the
net as I am in australia if I can not find them here

Regards

Anthony James