Date   
Re: using low voltage on DC fans

Greg Smith
 

Ken
Thank you for the information.  I have a couple of 12VDC fans – think I paid $2.00 for them – so as you say they are not expensive.  They do run on 3.3 and 5 VDC.  Mainly I was curious as to their likely longevity and also to find a use for the 3.3 VDC outputs.   One sure way to find out is to run them and see if they last.  If they do not I will replace with 5VDC fans. 
I am new to this and many basic (dumb) questions are forth coming.
 
Greg Smith
ps – I have checked the voltage output on the ATX power supply and all three voltages are very close to rating.

Re: PSX-AR Installation Query

Mark Gurries
 

This will not work under all conditions.

Any Engine or any car with multiple wheel electrical pickup will still short the two rails together as long as the TRUCK, not just a wheel spans over the gap (insulated rail joint).

So if you engine is crossing the gaps one one end of the reversing section and a passenger car is still crossing the other end gaps, you will still get a short circuit failure.



On Jan 20, 2020, at 12:33 PM, Chuck <railfan@...> wrote:

To avoid the metal wheel problem, simply glue a piece of styrene into
the gap and when dry sand or file to match the rail. The wheels will no
longer contact both rails at the same time.

Chuck

On 2020-01-20 3:03 p.m., mgj21932 via Groups.Io wrote:
Pete. Your metal wheels explanation makes absolute sense. Thanks
Bill


On Jan 20, 2020, at 2:58 PM, Pete via Groups.Io
<Kayakerpc=yahoo.com@groups.io> wrote:

As it was explained to me...
If you are running metal wheels, every pair of wheels that crosses
the polarity gap will cause the Auto Reverser to switch the polarity
if there is a difference, so if your loco hits a second gap before the
whole train is through that section, the loco will switch the polarity
again and then the wheels of the cars behind that cross the first gap
will switch the polarity again before the whole train is through
Your AR will be flipping back and forth as each set of wheels hit the
two gaps.
I hope I interpreted this correctly as I am new to DCC wiring too, but
I'm following the advice that was given to me as it makes sense.
Pete


Best Regards,

Mark Gurries
Electrical Engineer
DCC Website & NMRA DCC Clinics: www.markgurries.com

Re: Converting to DCC

Pete
 

Thanks Paul,

I,ve re-gapped my layout as suggested.
I see I will need one AR  for the lower yard.

Can I get by with one AR for the upper isolated section?
(I can't see why I would need one at each end, wouldn't they both trip when either end gets a short?)


I've been reading about dividing the layout into multiple power districts.
Is this something I should consider being that my layout isn't that big?
The upper and lower yards are already sepperate busses. Is that enough?
What more would I seperate?

Thanks,
Pete - Bellevue(Eastgate), Wa

Re: using low voltage on DC fans

 

The fans are in reality brush-less DC motors and therefore rely on internal electronics to make them rotate.  What happens when you under drive them therefore cannot be predicted.  Some fans are rated to work down to 5 Volts but others don't say.  If you give me the model and part number I will see if I can find its' electrical rating.

These are not costly devices so why not purchase one rated for what you want to do.  3.3V are rare but if you can run at 5 Volts can find a lot of choices.

https://www.digikey.com/product-detail/en/cui-devices/CFM-5010V-052-300/102-4365-ND/7620539

Be sure to check the actual output of your ATX supply as they are designed for heavy loads on the low voltage outlets and may not regulate properly without such.

Best Regards,

Ken Harstine

Re: Reversing Sections.

mgj21932
 

Excellent point.  And, yes, at least one of my new AR segments is now substantially larger and likely would have two trains on it.
 Hex Juicer will supply 1.7 amps to track.  I believe that ought to be sufficient for two efficient DCC Locos in one segment.  Will put track feeders at regular intervals.  
Bill


On Jan 27, 2020, at 8:49 AM, whmvd <vandoornw@...> wrote:


Bill,

Before you get rid of it, there is another consideration. Reducing the number of AR sections often involves making the newly chosen ones larger, or designing them so that entire stations or yards find themselves in one. That is in itself fine and can be crafty, but: keep in  mind that auto-reversers have a current limit that is usually considerably lower than what the regular track power is able to deliver.

Initial AR determination usually aims at smaller sections of single track, and that as a matter of course keeps the current draw in the section smallish. Re-thinks often cause individual AR sections to have to handle more than one train. so if you find the new design does that, have a careful look at the maximum power you expect to draw - and whether the AR can actually provide that.

Wouter

On Mon, 27 Jan 2020 at 04:13, mgj21932 via Groups.Io <mgj21932=yahoo.com@groups.io> wrote:
Yup.  Should have been able to save $$.  But had already bought reversing circuitry.  Now have an unused Tam Valley Hex juicer.  Anyone need one?  LOL!   
Novice mistake, but better to catch now than later.  And very much appreciate help and advice from this group.  
Bill D. 


On Jan 26, 2020, at 10:17 PM, Carl <carl.blum@...> wrote:



Hi:

I would make a diagram of the track connections and search for the minimum of reversing sections.

On Jim's layout he designed it as a folded and twisted DogBone and planned the reversing loops based on the DogBone route not requiring any. This resulted in three connections that had to be reversing blocks. When I looked at it as either clockwise or counter clockwise around the room there were only two reversing blocks. If you were depending on buying auto-reversers this would be a 33% savings.

Carl.

On 1/26/2020 10:04 PM, Steve Haas wrote:

>>>> I am a little curious why so many reversing sections – are you sure they all are actually that? <<<<

 

I have the same curiosity too, Max.  I’ve DL’d the track plan but have not had the time to properly analyze it to see what is really needed in terms of reversing sections and reversers.  Sometimes the track that creates the need for a reverser is not the track where the reverser should be used.

 

Best regards,

 

Steve

 

 

Steve Haas

Snoqualmie, WA

Re: Reversing Sections.

whmvd
 

Bill,

Before you get rid of it, there is another consideration. Reducing the number of AR sections often involves making the newly chosen ones larger, or designing them so that entire stations or yards find themselves in one. That is in itself fine and can be crafty, but: keep in  mind that auto-reversers have a current limit that is usually considerably lower than what the regular track power is able to deliver.

Initial AR determination usually aims at smaller sections of single track, and that as a matter of course keeps the current draw in the section smallish. Re-thinks often cause individual AR sections to have to handle more than one train. so if you find the new design does that, have a careful look at the maximum power you expect to draw - and whether the AR can actually provide that.

Wouter


On Mon, 27 Jan 2020 at 04:13, mgj21932 via Groups.Io <mgj21932=yahoo.com@groups.io> wrote:
Yup.  Should have been able to save $$.  But had already bought reversing circuitry.  Now have an unused Tam Valley Hex juicer.  Anyone need one?  LOL!   
Novice mistake, but better to catch now than later.  And very much appreciate help and advice from this group.  
Bill D. 


On Jan 26, 2020, at 10:17 PM, Carl <carl.blum@...> wrote:



Hi:

I would make a diagram of the track connections and search for the minimum of reversing sections.

On Jim's layout he designed it as a folded and twisted DogBone and planned the reversing loops based on the DogBone route not requiring any. This resulted in three connections that had to be reversing blocks. When I looked at it as either clockwise or counter clockwise around the room there were only two reversing blocks. If you were depending on buying auto-reversers this would be a 33% savings.

Carl.

On 1/26/2020 10:04 PM, Steve Haas wrote:

>>>> I am a little curious why so many reversing sections – are you sure they all are actually that? <<<<

 

I have the same curiosity too, Max.  I’ve DL’d the track plan but have not had the time to properly analyze it to see what is really needed in terms of reversing sections and reversers.  Sometimes the track that creates the need for a reverser is not the track where the reverser should be used.

 

Best regards,

 

Steve

 

 

Steve Haas

Snoqualmie, WA

Re: Reversing Sections.

Don Vollrath
 

I said that earlier Carl. Draw it out A figure eight plus sides to form an outside continuous loop is the same as a folded dog bone ... with main lines expanded in the area of the crossover. Only two AR sections. One at each end of the continuous loop Everything in the middle can be / is constant polarity.
DonV

Re: Reversing Sections.

mgj21932
 

Yup.  Should have been able to save $$.  But had already bought reversing circuitry.  Now have an unused Tam Valley Hex juicer.  Anyone need one?  LOL!   
Novice mistake, but better to catch now than later.  And very much appreciate help and advice from this group.  
Bill D. 


On Jan 26, 2020, at 10:17 PM, Carl <carl.blum@...> wrote:



Hi:

I would make a diagram of the track connections and search for the minimum of reversing sections.

On Jim's layout he designed it as a folded and twisted DogBone and planned the reversing loops based on the DogBone route not requiring any. This resulted in three connections that had to be reversing blocks. When I looked at it as either clockwise or counter clockwise around the room there were only two reversing blocks. If you were depending on buying auto-reversers this would be a 33% savings.

Carl.

On 1/26/2020 10:04 PM, Steve Haas wrote:

>>>> I am a little curious why so many reversing sections – are you sure they all are actually that? <<<<

 

I have the same curiosity too, Max.  I’ve DL’d the track plan but have not had the time to properly analyze it to see what is really needed in terms of reversing sections and reversers.  Sometimes the track that creates the need for a reverser is not the track where the reverser should be used.

 

Best regards,

 

Steve

 

 

Steve Haas

Snoqualmie, WA

Re: Feeder line issues

mgj21932
 

Based on Max’s inquiry I reviewed the layout and despite large number of DC blocks found that I only need 3 reversing segments!  
Thanks Max. 


On Jan 26, 2020, at 10:04 PM, Steve Haas <Goatfisher2@...> wrote:



>>>> I am a little curious why so many reversing sections – are you sure they all are actually that? <<<<

 

I have the same curiosity too, Max.  I’ve DL’d the track plan but have not had the time to properly analyze it to see what is really needed in terms of reversing sections and reversers.  Sometimes the track that creates the need for a reverser is not the track where the reverser should be used.

 

Best regards,

 

Steve

 

 

Steve Haas

Snoqualmie, WA

Reversing Sections.

Carl
 

Hi:

I would make a diagram of the track connections and search for the minimum of reversing sections.

On Jim's layout he designed it as a folded and twisted DogBone and planned the reversing loops based on the DogBone route not requiring any. This resulted in three connections that had to be reversing blocks. When I looked at it as either clockwise or counter clockwise around the room there were only two reversing blocks. If you were depending on buying auto-reversers this would be a 33% savings.

Carl.

On 1/26/2020 10:04 PM, Steve Haas wrote:

>>>> I am a little curious why so many reversing sections – are you sure they all are actually that? <<<<

 

I have the same curiosity too, Max.  I’ve DL’d the track plan but have not had the time to properly analyze it to see what is really needed in terms of reversing sections and reversers.  Sometimes the track that creates the need for a reverser is not the track where the reverser should be used.

 

Best regards,

 

Steve

 

 

Steve Haas

Snoqualmie, WA

Re: Feeder line issues

Steve Haas
 

>>>> I am a little curious why so many reversing sections – are you sure they all are actually that? <<<<

 

I have the same curiosity too, Max.  I’ve DL’d the track plan but have not had the time to properly analyze it to see what is really needed in terms of reversing sections and reversers.  Sometimes the track that creates the need for a reverser is not the track where the reverser should be used.

 

Best regards,

 

Steve

 

 

Steve Haas

Snoqualmie, WA

Re: using low voltage on DC fans

Steve Haas
 

 

>>>>> I am using an ATX power supply for my Tortise switch machines.  I have a number of 3.3 VDC and 5 VDC wires that at present are not being used.  Can I use 3.3 or 5 VDC on 12 VDC fans without damaging the motors in the long run?  They run okay, a bit slower than when on 12 VCD of course. <<<<<

 

Greg,

 

You’ll be fine.  What you propose to do is roughly the equivalent of running a good old fashion 12 DC motor in an old Athearn engine at somewhere around  27% and 42% of full throttle on that old Power Pack you got with that first train set so many years ago.

 

Best regards,

 

Steve

 

Steve Haas

Snoqualmie, WA

Re: Feeder line issues

mgj21932
 

Max, 

I've attached a diagram of the track layout.  One is just a diagram of the track layout (all black).  The second is in color and identifies the individual reversing segments.  (The black siding on the colored version is electrically and physically isolated from the rest of the layout.  It will operate on DC and can be used by grandchildren to operate a switching engine and freight cars.)   The green mainline passes over the blue line via a bridge, as does the yellow siding.  The siding is on a plateau above the blue loop line.  With the exception of the yellow siding, most of the left quarter of the layout is in tunnels under a mountain.  

As you can see, the basic figure 8 design can be reversed in both directions.  That capability is the defining characteristic of the track plan.  

The yellow siding doesn't have to be a reversing section and will probably be wired with the green mainline segment to which it is connected.  Thee is really no need for it to be an AR segment because, with DCC, I can operate a train on that siding independently of what's going on in the mainline; and even if the polarity on the mainline switches, that should not affect operation of a DCC controlled locomotive on the siding.  Had considered wiring as separate reversing segment only to reduce length of 22 AWG feeder lines.

Because of the double reverse arrangment, there are what I would describe as "intermediate" reversing segments that increase the total.  A simple reverse would require 3 segments.  The addition of a second reversing capability splits one of the first three reversing segments and adds another segment, for total of 5.  

The layout has the capacility to run a train on the figure 8 pattern without any switching issues.  Throw a couple of switches and the train reverses; then return those switches and the train continues in reverse around the figure 8.  Throwing a couple of more switches and an almost endless variety of patterns is possible.  I wanted the flexibility for great variety on a small (5' x 9') layout.

I don't encounter any difficulty using 14 AWG directly from the bus on the input side of the hex juicer.  But 15' of 22 AWG feeder line from the frog juicer to the track seems a bit long.  I've asked Duncan McCree (Tam Valley) about that, and have not received an answer yet.  If he tells me that no significant operational issues have been presented by 15' long 22 AWG feeder wires, then I should be in great shape with just 3'-4' of 22 AWG feeder lines from the outputs of the hex juicer.  

Nevertheless, the safer solution might be to splice in a 14 AWG segment from the 22 AWG "stub" wire at the output of the hex juicer to within about 6" of the connection with the track.  The downside of doing so of course is risk of splice failure and possible signal degredation due to the splices.  Do you think that exercise is unnecessary?  

Bill D

On Saturday, January 25, 2020, 03:10:16 PM EST, Max Maginness <m.maginness@...> wrote:

If I recall you wanted to use 20ga wire from the track connections to the juicer terminals. 4 feet of this has a resistance of about 0.04 ohms. This does not matter, some small resistance is actually needed to control  the peak current flow.

In fact the hex juicer instructions read:

“Use #22 or bigger wire (up to 3 feet from the bus) on the input side of the board and between the frogs use #28-22 ga. wire (up to 15 feet from the frog to the juicer)”

I am a little curious why so many reversing sections – are you sure they all are actually that?

Max

And BTW, I just checked – the terminals on the juicers will take up to 12 ga. Wire but as   above,  its not required or recommended   for the frogs and might only be used for a very  long connection from the juicer to the main DCC bus.

From: w4dccqa@groups.io <w4dccqa@groups.io> On Behalf Of mgj21932 via Groups.Io

Sent: Saturday, January 25, 2020 6:23 AM
To: w4dccqa@groups.io
Subject: Re: [w4dccqa] Feeder line isues

Yes.  All in single power district.  

Planning to address the concern about voltage loss on 3’-4’ feeders by spicing in 14 AWG wire for most of the length.  

Do you have an opinion on electric conductivity efficiency of soldered vs physical butt connections?  

On Jan 25, 2020, at 8:54 AM, Max Maginness <m.maginness@...> wrote:
The Hex juicers were really intended for   turnout frogs in a dense area like a yard throat. The dual ones are much more suited for scattered reversing loops. (and of course the single ones for isolated turnout frogs)
BTW are all  your  reversing sections in the same power district? If not the hex scheme won’t work.
To late to do an exchange?
Max
From: w4dccqa@groups.io <w4dccqa@groups.io> On Behalf Of mgj21932 via Groups.Io

Sent: Friday, January 24, 2020 5:43 AM
To: w4dccqa@groups.io
Subject: Re: [w4dccqa] Feeder line isues

Thought about that Max but 2 Hex juicers were much cheaper than six dual juicers.  So bought Hex juicers to save a few bucks.  Did not realize limit on size of output wires until the Hex juicers arrived and I could physically inspect them.  Live and learn.  

BillD

On Jan 24, 2020, at 8:37 AM, Max Maginness <m.maginness@...> wrote:

Why not use the dual juicers. One per reversing section.

 Max

Re: Feeder line issues

Max Maginness
 

If I recall you wanted to use 20ga wire from the track connections to the juicer terminals. 4 feet of this has a resistance of about 0.04 ohms. This does not matter, some small resistance is actually needed to control  the peak current flow.

In fact the hex juicer instructions read:

 

“Use #22 or bigger wire (up to 3 feet from the bus) on the input side of the board and between the frogs use #28-22 ga. wire (up to 15 feet from the frog to the juicer)”

I am a little curious why so many reversing sections – are you sure they all are actually that?

 

Max

And BTW, I just checked – the terminals on the juicers will take up to 12 ga. Wire but as   above,  its not required or recommended   for the frogs and might only be used for a very  long connection from the juicer to the main DCC bus.

 

From: w4dccqa@groups.io <w4dccqa@groups.io> On Behalf Of mgj21932 via Groups.Io
Sent: Saturday, January 25, 2020 6:23 AM
To: w4dccqa@groups.io
Subject: Re: [w4dccqa] Feeder line isues

 

Yes.  All in single power district.  

Planning to address the concern about voltage loss on 3’-4’ feeders by spicing in 14 AWG wire for most of the length.  

 

Do you have an opinion on electric conductivity efficiency of soldered vs physical butt connections?  



On Jan 25, 2020, at 8:54 AM, Max Maginness <m.maginness@...> wrote:



The Hex juicers were really intended for   turnout frogs in a dense area like a yard throat. The dual ones are much more suited for scattered reversing loops. (and of course the single ones for isolated turnout frogs)

 

BTW are all  your  reversing sections in the same power district? If not the hex scheme won’t work.

 

To late to do an exchange?

Max

 

From: w4dccqa@groups.io <w4dccqa@groups.io> On Behalf Of mgj21932 via Groups.Io
Sent: Friday, January 24, 2020 5:43 AM
To: w4dccqa@groups.io
Subject: Re: [w4dccqa] Feeder line isues

 

Thought about that Max but 2 Hex juicers were much cheaper than six dual juicers.  So bought Hex juicers to save a few bucks.  Did not realize limit on size of output wires until the Hex juicers arrived and I could physically inspect them.  Live and learn.  

BillD




On Jan 24, 2020, at 8:37 AM, Max Maginness <m.maginness@...> wrote:



Why not use the dual juicers. One per reversing section.

 

Max

Re: Feeder line isues

mgj21932
 

Yes.  All in single power district.  
Planning to address the concern about voltage loss on 3’-4’ feeders by spicing in 14 AWG wire for most of the length.  

Do you have an opinion on electric conductivity efficiency of soldered vs physical butt connections?  


On Jan 25, 2020, at 8:54 AM, Max Maginness <m.maginness@...> wrote:



The Hex juicers were really intended for   turnout frogs in a dense area like a yard throat. The dual ones are much more suited for scattered reversing loops. (and of course the single ones for isolated turnout frogs)

 

BTW are all  your  reversing sections in the same power district? If not the hex scheme won’t work.

 

To late to do an exchange?

Max

 

From: w4dccqa@groups.io <w4dccqa@groups.io> On Behalf Of mgj21932 via Groups.Io
Sent: Friday, January 24, 2020 5:43 AM
To: w4dccqa@groups.io
Subject: Re: [w4dccqa] Feeder line isues

 

Thought about that Max but 2 Hex juicers were much cheaper than six dual juicers.  So bought Hex juicers to save a few bucks.  Did not realize limit on size of output wires until the Hex juicers arrived and I could physically inspect them.  Live and learn.  

BillD



On Jan 24, 2020, at 8:37 AM, Max Maginness <m.maginness@...> wrote:



Why not use the dual juicers. One per reversing section.

 

Max

Re: Feeder line isues

Max Maginness
 

The Hex juicers were really intended for   turnout frogs in a dense area like a yard throat. The dual ones are much more suited for scattered reversing loops. (and of course the single ones for isolated turnout frogs)

 

BTW are all  your  reversing sections in the same power district? If not the hex scheme won’t work.

 

To late to do an exchange?

Max

 

From: w4dccqa@groups.io <w4dccqa@groups.io> On Behalf Of mgj21932 via Groups.Io
Sent: Friday, January 24, 2020 5:43 AM
To: w4dccqa@groups.io
Subject: Re: [w4dccqa] Feeder line isues

 

Thought about that Max but 2 Hex juicers were much cheaper than six dual juicers.  So bought Hex juicers to save a few bucks.  Did not realize limit on size of output wires until the Hex juicers arrived and I could physically inspect them.  Live and learn.  

BillD



On Jan 24, 2020, at 8:37 AM, Max Maginness <m.maginness@...> wrote:



Why not use the dual juicers. One per reversing section.

 

Max

using low voltage on DC fans

Greg Smith
 

I am using an ATX power supply for my Tortise switch machines.  I have a number of 3.3 VDC and 5 VDC wires that at present are not being used.  Can I use 3.3 or 5 VDC on 12 VDC fans without damaging the motors in the long run?  They run okay, a bit slower than when on 12 VCD of course.
Greg
ps - I am going to set the fans up behind my Digitrax Command Station and Boosters for a bit of extra cooling.

Re: Feeder line isues

mgj21932
 

Thought about that Max but 2 Hex juicers were much cheaper than six dual juicers.  So bought Hex juicers to save a few bucks.  Did not realize limit on size of output wires until the Hex juicers arrived and I could physically inspect them.  Live and learn.  
BillD


On Jan 24, 2020, at 8:37 AM, Max Maginness <m.maginness@...> wrote:



Why not use the dual juicers. One per reversing section.

 

Max

Re: Feeder line isues

Max Maginness
 

Why not use the dual juicers. One per reversing section.

 

Max

Re: Feeder line isues

mgj21932
 

Thanks for the advice DonV. Will be sure to make good solid connections.
BillD

On Jan 24, 2020, at 5:58 AM, Don Vollrath <donevol43@...> wrote:

It is the overall in series resistance of the current path that limits the peak flow of current necessary to operate the AR unit. Twisted then soldered Wire to wire connections will provide a minimum of overall resistance to the intended current path. So make your own wire size transition using a short piece of 20/22 Awg soldered to the longer length of 14awg feeder wire at each end. Good alternatives include a solid barrel crimp splice.
DonV