Can anybody explain to me why this is bad if the two transformers are the same voltage and phased?
Thanks,
Dave
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No, I can't. I do know that one then needs a device to control the voltage and current sufficient for the doubled current as well as wiring. The Lionel TPC and the awaited Legacy Powermaster 360 bind 2 10amp supplies.
it's also easy to cook other devices with twice the current. Ups the requirement for layout power and control to 20 amps handling.
Elliot does it with 3 small supplies for each block on his dream/nightmare layout, but isn't exceeding 10amps.
Moonman said it best. It is a bad idea, because 18volts at 10 amps is about the limit of most train circuits. You can find single power supplies that do this much more efficiently, with more safety than stacking two lesser supplies.
David Minarik posted:Can anybody explain to me why this is bad if the two transformers are the same voltage and phased?
I can probably dig out a couple of passenger cars that derailed on a switch with 20 amps on the rails to illustrate the point, but suffice to say that it's welding country when you get that much current on the rails.
Another point is most electronic transformers simply won't allow this without issues. Also minor differences in the circuit breakers and the impedance of the wiring from each transformer may cause one to trip prematurely or not at all.
I am trying to get around the '5 engine per TIU channel limit'. The extra power does allow more than 5 engines to function properly so it is a power limitation not a processor limitation.
I'm not a fan of having to toggle tracks in yards and engine facilities on and off.
Thanks for the input!
Dave
If you have more than 10 amps, you have to run in passive mode for the TIU, it only does 10A maximum for each channel.
David Minarik posted:I am trying to get around the '5 engine per TIU channel limit'. The extra power does allow more than 5 engines to function properly so it is a power limitation not a processor limitation.
I'm not a fan of having to toggle tracks in yards and engine facilities on and off.
Thanks for the input!
Dave
Done the Parallel transformer power out but then did fuses per track. Power up for the whole system and back to 7.5 amps per track circuit. Maybe that's what you got in mind.
This is older PH135's Paralleled (lower left). Recently added the TIU in passive mode. Near the Acme accessory transformer top left are (8) track circuit fuses (7.5 amps each) Parallel power from the transformers is circuited to the (2) TPC's (Track Power Controllers) bottom Right and then to the (2) BPC (Block Power Controllers) below the Track fuses.
TIU installed passive mode. As pictured it supplies DCS signal to the (8) track circuits.
Let me know if you need for me to stop at the shop or your home,
We also do Parllel PH 180's for the Fort Pitt High Railer's, Turntable/House modules.
Best wishes Mike CT. Give me a call.
David,
Using Power Districts would be safer for your trains where you use more than one channel per loop. That way you don't need more than 10 amps per district and no welding from high amperage.
Mike CT posted:David Minarik posted:I am trying to get around the '5 engine per TIU channel limit'. The extra power does allow more than 5 engines to function properly so it is a power limitation not a processor limitation.
I'm not a fan of having to toggle tracks in yards and engine facilities on and off.
Thanks for the input!
Dave
Done the Parallel transformer power out but then did fuses per track. Power up for the whole system and back to 7.5 amps per track circuit. Maybe that's what you got in mind.
This is older PH135's Paralleled (lower left). Recently added the TIU in passive mode. Near the Acme accessory transformer top left are (8) track circuit fuses (7.5 amps each) Parallel power from the transformers is circuited to the (2) TPC's (Track Power Controllers) bottom Right and then to the (2) BPC (Block Power Controllers) below the Track fuses.
TIU installed passive mode. As pictured it supplies DCS signal to the (8) track circuits.
Let me know if you need for me to stop at the shop or your home,
We also do Parllel PH 180's for the Fort Pitt High Railer's, Turntable/House modules.
Best wishes Mike CT. Give me a call.
Very clean and well engineered set up. I as well 7.5 amp fast blow per track circuit.
David Minarik posted:I am trying to get around the '5 engine per TIU channel limit'. The extra power does allow more than 5 engines to function properly so it is a power limitation not a processor limitation.
I'm not a fan of having to toggle tracks in yards and engine facilities on and off.
Thanks for the input!
Dave
Am i over the limit ?..I am currently running 8 powered (2 mu 4 each) with no issues.
gunrunnerjohn posted:If you have more than 10 amps, you have to run in passive mode for the TIU, it only does 10A maximum for each channel.
I am.
In the largescale DCS world we run 24-30V DC @ 25 amps all day in passive mode and no that's not welding currents...unless of course you try welding paperclips together.
The welding machines I've used were equipped with 40-70V OCV and capable of generating anywhere from 100 - 1,500 amps. Well you know David as you guys weld on bikes and stuff.
Casey Jones2 posted:In the largescale DCS world we run 24-30V DC @ 25 amps all day in passive mode and no that's not welding currents...unless of course you try welding paperclips together.
20-30 amps will take a nice divot out of a wheel flange on a derailment, I have proof positive.
Elliot has 20 amps to the track with PTC re-settable fuses to control current since the PTC's have a response time in the tens of seconds and Ive seen the wheels glow cherry red hot on a derail before anybody can get there and shut off the power.
Even non-electronic transformers shouldn't be "stacked"---outputs connected in parallel. A slight difference in voltages will create stray currents in the internal wiring which could cause pinpoint overheating.
I never told my layout of any limit on locos per channel, so it blissfully goes on its way handling whatever the brass hat sends.
Matt, I've personally witnessed it, sadly with one of my passenger cars! We had 20A on the rails for one day at a modular show because we were having wiring issues and paralleled the transformers to put a bandaid on the issue. Naturally, I was the victim that came around and derailed on a flaky switch, now there's a nice little notch in the flange of a wheel on one passenger car. I took my stuff off and didn't run until we were able to spend the time to fix the wiring properly.
20 amps is too much in my opinion and a derail could do some pretty bad damage. I smoked out a legacy sound board derailing across 2 separate power districts. Cost me $90 to fix that one
Doing this does seem to solve the five engine limit per TIU channel confirming that it is indeed a power issue not a processing issue.
C Jones, yeah 20 amps is not going to weld much. Left unchecked, it will melt things. (sounds like what happened to John)
Dave
David,
I'd worry more about 20 amps taking out the electronics in the engine the most.
Joe Allen posted:David,
I'd worry more about 20 amps taking out the electronics in the engine the most.
Even 150 amps won't take out the electronics. You're mixing issues here, your concern about electronics probably comes from concerns about transients & spikes.
David Minarik posted:Doing this does seem to solve the five engine limit per TIU channel confirming that it is indeed a power issue not a processing issue.
C Jones, yeah 20 amps is not going to weld much. Left unchecked, it will melt things. (sounds like what happened to John)
Dave
It was left unchecked for all of around ten seconds, it really doesn't take long.
Gosh i wish someone would have told me about a 5 engine limit. When did that come about ? Darn after I was having so much fun running 16 powered locomotives in six trains on a single loop for 2 hours. Hmmm I was using all four channels though.
Clem
Was thought up a few weeks ago.
clem k posted:Gosh i wish someone would have told me about a 5 engine limit. When did that come about ? Darn after I was having so much fun running 16 powered locomotives in six trains on a single loop for 2 hours. Hmmm I was using all four channels though.
Clem
Don't believe me?
Once they are started they might be fine. Put 5 on one channel, everything will be OK. Add one, especially PS3 engines, and you will have startups and slow response when finding engines. Once they are started you might be fine.
Your math suggests 4 engines per channel. What are you saying??????
RJR posted:Was thought up a few weeks ago.
I would be interested in hearing your experience too?
I had posted my experience in another thread. I placed 7 locos on a channel. Turned on power. They were quiet. Pressed startup all, and they all started right up at the same time.
RJR posted:I had posted my experience in another thread. I placed 7 locos on a channel. Turned on power. They were quiet. Pressed startup all, and they all started right up at the same time.
I don't believe this was something that was 'thought up a few weeks ago' as your post states. After reading the suggestion and having some issues myself, I tried reducing my engine number to five and discovered that it seemed to be the limit for engines with perfect performance. These were in two areas known to have signal issues. One was a yard. The other is a roundhouse/engine facility.
When the engines are spread out, this doesn't seem to be so much of an issue.
Post if you have something positive to add, otherwise, please feel free to not.
Dave
Years ago, just to find out how many engines could be programmed in a Lash-up, using 1 channel of the TIU and a Z-4000 voltage turn all the way up, I programmed 8 diesels and 2 steam engines in a Lash-up.
All started up and ran fine and I could run them up to 35 MPH. Any higher and the Z-4000 red light would start to blink.10 engines is the maximum that the remote would allow for a Lash-up. This was with no smoke turned on and nothing but the engines on the track on 1 loop.
I forget what Version of DCS I was using at the time and I don't know if has changed with the newer Versions.
P.S. These were all PS2 engines before PS3
You asked. You don't have to get snotty if you don't like the answer.
This is only to confirm "chunks" and spew some memories, I don't know how they were hooked up. But the sections on my Grandfather's layout used two "hot rodded" ZWs each, 6 total at its peak on two post war lines.
One ZW per pair was powered up fully at start, the other would do the controlling. External beakers tripped fast, but still took a few chunks out of wheels, etc. They were not allowed to run unattended.
The ABBA SF 6 motors was daily, I could run them solo.
ABBBA, or ABBA with seven pulmor motors was there under supervision. The big one could pull two dozen lit streamliners, the short was 22. 12-16 was normal. And triple headed FMTMs on the other main line were also ran. Normally double headed freight, but heavy Madison's were there too.
Eventually, only the Santa Fe line had two. The 7 motor MUs absolutely needed it for good running.
The hot rodding was done by an electical engineer at the steel plant he worked at.
A #11 bucket and a MIG welder with 20-25a is all I need for pretty beads on thin sheet metal for modern automobiles 
I've not seen lower than a 20a setting.
I've not seen lower than a 20a setting.The parallel PH 135's, that I pictured, with the 7.5 amp per track circuit limit, do a decent job with this consist. The Pittsburg and Shawmut Railroad did this consist regularly. We had done this consist, on a Z 4000 track circuit, with amp meters, it pushes 7. Done with Atlas SW 9 and a GP7, early TMCC. GP7 has EOB electronics. Mouse over image and Click on the triangle lower left corner. The Lionel part number for the Parallel connector (TPC cable set) (6-14194)
These two PH 180's on the Fort Pitt Highrailer's Turntable model use the Lionel part listed above to connect to the TPC (Silver box, Track Power controller) This high amperage track circuit is then connected to the DCS pictured. Fixed one In and Fixed two In. Two track circuits out power all the turntable spurs. Not pretty but it does work for at least 12 engines/locomotives.
Mike CT posted:The parallel PH 135's, that I pictured, with the 7.5 amp per track circuit limit, do a decent job with this consist. The Pittsburg and Shawmut Railroad did this consist regularly. We had done this consist, on a Z 4000 track circuit, with amp meters, it pushes 7. Done with Atlas SW 9 and a GP7, early TMCC. GP7 has EOB electronics. Mouse over image and Click on the triangle lower left corner.
These two PH 180's on the Fort Pitt Highrailer's Turntable model use the Lionel part listed above to connect to the TPC (Silver box, Track Power controller) This high amperage track circuit is then connected to the DCS pictured. Fixed one In and Fixed two In. Two track circuits out power all the turntable spurs. Not pretty but it does work for at least 12 engines/locomotives.
Just to confirm..A TPC 300 will combine 2 135's and a TPC 400 will combine either 2 135's or 2 180's?
willygee posted:Mike CT posted:The parallel PH 135's, that I pictured, with the 7.5 amp per track circuit limit, do a decent job with this consist. The Pittsburg and Shawmut Railroad did this consist regularly. We had done this consist, on a Z 4000 track circuit, with amp meters, it pushes 7. Done with Atlas SW 9 and a GP7, early TMCC. GP7 has EOB electronics. Mouse over image and Click on the triangle lower left corner.
These two PH 180's on the Fort Pitt Highrailer's Turntable model use the Lionel part listed above to connect to the TPC (Silver box, Track Power controller) This high amperage track circuit is then connected to the DCS pictured. Fixed one In and Fixed two In. Two track circuits out power all the turntable spurs. Not pretty but it does work for at least 12 engines/locomotives.
Just to confirm..A TPC 300 will combine 2 135's and a TPC 400 will combine either 2 135's or 2 180's?
Yes, I believe the TPC 300 has a 15 amp circuit breaker, I've never experienced one, for sure the TPC 400's have a 20 amp circuit breaker as part of the assembly, I have never popped/opened the circuit breaker on a TPC 400, something else always opened/went first. The two (2) 7.5 amp breakers on the two PH135, hooked parallel, would open simultaneously. Also the resets on PH180's seem to open very quickly. Also the 7.5 amp track fuses need replaced frequently on de-rails.
Seem to me mixing apples, oranges and pineapples in this discussion. Power needs, versus Tiu Limitations, and the specifics of welding
First, while a manufacturer or home inspector would not give approval, I have seen 4 to 5 Power House 180Watt transformers phased and paralleled to feed a block. Five sets of these where used to power 5 blocks on a TMCC/Legacy layout.
This was done so that 4 dual pulmore motor engines run in an MU with lighted passenger cars, and 3 to 4 sets of these trains where run on a 1200ft layout. At times 2 of these units would be on the same block, hence 8 dual pulmore motors and lighted cars being powered. Hence the need for MORE POWER
It worked fine....until a derailment. There was a master kill switch but you had to be quick, usually significant damage if not.
Do not know if you call it welding, but having wheels molten or large pitting holes in a truck block, sure looked like the metal melted. So call that what you will.
Since this power was applied directly to the blocks, and a Legacy Command base on the ground this worked. The Power Houses seemed to have no issue and shared the load. I would assumed if you ran near a limit. Like 38amps drawn on 40amps provided, you might have a weaker PH kick out. At that point you have 30amps trying to feed a 38A load, and the others would kick out on overload. But this layout did not have continuity of power issues.
The problem with a DCS set up is you pass power through TIU unless you go passive. The Traces can handle 20amps, but the VAR output FET probably could not. So your limited by TIU without going passive, unless you only needed around 12-15Amps and just went with 2 180W PHs. Give it a shot. I imagine a blown TIU fuse or maybe a toast TIU would be the worst to occur. Other than train damage with a derailment. G
David Minarik posted:clem k posted:Gosh i wish someone would have told me about a 5 engine limit. When did that come about ? Darn after I was having so much fun running 16 powered locomotives in six trains on a single loop for 2 hours. Hmmm I was using all four channels though.
Clem
Don't believe me?
Once they are started they might be fine. Put 5 on one channel, everything will be OK. Add one, especially PS3 engines, and you will have startups and slow response when finding engines. Once they are started you might be fine.
Your math suggests 4 engines per channel. What are you saying??????
The limit use to be 10 locomotives per Barry's book and I think in the DCS video also said that. So when did it change ? or is this something you recently discovered, in which case thank you 
Note: The largest lash-ups I have built lately just happen to be five.
Some places on the track four of the six trains where on the same channel (300 foot loop) My blocks are large because I use 36 inch track. Before I used all four channels, (only 2) I would build seven unit lash-ups. That was on version 3 . something. I agree PS2 are by far more reliable then PS3. And PS2 converted to PS3 are better than PS3 locomotives. Large engine consist work better using the all command ,then in lash-up mode.
The problem I have is I need all the power districts to turn off if only one trips (long trains).
Clem
The only parallel arrangement that I see that makes any sense is having a power "pool" and separate circuit breakers for every track feed. You might be able to save a transformer or two with that arrangement, hard to say. That limits the track power to any specific part of the layout to a reasonable level.
However, supplying 30-30-40 amps directly to the rails without limiting the current sounds like lunacy to me.
The limit for lashups is 10 DCS engines. The limit for the total # of engines per channel is dependent on available power and other factors.
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RJR posted:You asked. You don't have to get snotty if you don't like the answer.
Your original post contributed nothing. If the shoe fits.......
clem k posted:David Minarik posted:clem k posted:Gosh i wish someone would have told me about a 5 engine limit. When did that come about ? Darn after I was having so much fun running 16 powered locomotives in six trains on a single loop for 2 hours. Hmmm I was using all four channels though.
Clem
Don't believe me?
Once they are started they might be fine. Put 5 on one channel, everything will be OK. Add one, especially PS3 engines, and you will have startups and slow response when finding engines. Once they are started you might be fine.
Your math suggests 4 engines per channel. What are you saying??????
The limit use to be 10 locomotives per Barry's book and I think in the DCS video also said that. So when did it change ? or is this something you recently discovered, in which case thank you
Some places on the track four of the six trains where on the same channel (300 foot loop) My blocks are large because I use 36 inch track. Before I used all four channels, (only 2) I would build seven unit lash-ups. That was on version 3 . something. I agree PS2 are by far more reliable then PS3. And PS2 converted to PS3 are better than PS3 locomotives. Large engine consist work better using the all command ,then in lash-up mode.
The problem I have is I need all the power districts to turn off if only one trips (long trains).
Clem
Clem,
There was a post some time back where five seemed to be a limit for the number of engines to a TIU channel. It was posted that it was not clear if this was a limit of the TIU processor or a power issue. With my testing, it seems to be a power issue not a processor issue as everything worked fine when the transformers were stacked.
Keep in mind, that I was only experiencing these issues in my yard where I have a 'cage track' that houses a small fleet of end cab switchers. Anything over 5 engines on this track, caused odd start ups or slow response.
The other area of concern was my engine facility with a roundhouse.
The stacking adds enough power to make everything work but I was concerned about the dangers of doing so.
I will explore some other options before making permanent changes to the layout.
I'm just trying to learn as much about it as I can.
Dave
Great post Dave. Great because it pulls all the great minds together to come up with an answer.
When a toy train derails and the sparks fly, the temperature of the spark and the composition of the steel, is what will determine how much of a hole will be left from the spark. The quality of our train wheels don't seem to be the best and may melt at a lower temperature then what it takes when welding the standard A-36 structural steel that most of us have experience working with.
