This is a follow up to a thread I started several weeks ago. After adding about 6 new sound equipped locos to the layout, I began to experience system shutdowns which I believe was due to system overload. I am a lone wolf operator and at most, I will have two trains moving at one time, each of which might have two powered units for a maximum of 4 units under power at one time. Up until now, I have been using a single booster system and that had been sufficient until recently. It seems to me the total power draw of the units under power and those at rest had exceeded my 5 amp Lenz booster. I realized I had finally reached the point where a second booster would be required. In addition, I rigged on on/off switch to my roundhouse which has 14 stalls so that I could cut power there when I wasn't moving a loco in or out of the roundhouse. This had kept me in business while I am awaiting delivery of the second booster. Today, I put a few more locos on the track that had been on the shelf and it appears I have again reached overload.
I decided I needed to do something radical. I read the instruction manual. According to the Lenz manual, on average, an HO loco will draw 0.5 amps while moving so that means a total of 2.0 amps, well under the 5 amp limit. It went on to say that a loco at rest without lights draws only 1.5mA which I am guessing is 1.5 milliamps. However, it also tells me that with the headlight on, the draw will average 50mA. There is no mention of how much a sound equipped loco draws and I'm guessing that is because when the manual was written, sound hadn't become as prevalent as it is now. I would appreciate it if someone could tell me how much sound adds to this equation. I've tried shutting off sound and headlights when I park a loco, but when the system has been shutdown and restarted, all the headlights and sound come back on and it is a pain to go around shutting all of them off.
I just took inventory of how many locos I now have on the layout. There are 39 of them, 28 of which have sound. Right now, 15 of them are in the roundhouse, so when I have the power to the RH shut off, the system is able to operate. Today after I added a few more locos to the layout, I apparently reached the tipping point. When I turn power on to the RH, the system shuts down which I am almost certain is due to an overload. This happens even with no locos moving. According to my manual, 39 locos at rest with headlights on should only be drawing a total of about 2 amps if my math is correct. However, I don't know how much more I need to figure for the sound locos, so that is where I am guessing.
The plan is to divide the layout in two when I get the additional booster. Also, I'm thinking of adding a second on/off switch to the roundhouse so that I can turn on just 7 stalls at a time instead of all 14. I know there are many on this forum who are much more knowledgeable than myself about the electronic requirements and I would appreciate if someone can tell me if they think I am heading in the right direction or if there is something I am missing.
John,
I have a Digitrax DCC system with 5 amp booster. I have 6 'sound' engines and 5 other DCC engines on the layout. These consist of P2K/BLI/Atlas engines. I have never had a booster shutdown due to too many engines. At our club, we did shutdown the power district that controls the roundhouse area due to too many engines. Early QSI sound decoders have very large capacitors and the 'in-rush' current when powering up the layout can overload the booster. But we had well over 30 engines(many sound/DCC) at the roundhouse area - so that shutdown made sense.
Do you have a 5 amp power supply powering the booster? Also, you might want to remove one of the new engines and test - maybe one of them has a problem.
Jim
Modeling BNSF and Milwaukee Road in SW Wisconsin
I concur with Jim.
The only time I have a problem is if I am installing a decoder in a newly acquierd locomotive and the mechanism is binding. If that happens the fan in my DCC controller kicks on. If I keep increasing the throttle, sometimes it will reset.
I'd take off the last engine you put on, and then work backwards.
I have a PA (original, not squared) with no booster.
I currently have 4 BLI/QSI locomotives, 2 P2K/QSI, 2, PCM/ESU, 3 Atlas/ESU (home installed), and 1 P2K/TCS (the only one without sound), and never any current or shutdown issues unless one shorts due to derailing.
This is actually a pretty light population, as I just took off about a half dozen others (all with one or another sound decoder) for some construction and modification projects.
I usually actually operate 2 locos at a time, but sometimes one is a consist of 2 or 3 units.
The others on on powered track, just not actively addressed. Sometimes, however, I'll use one for a while, then swicth to another, so the first (or second, etc) is still idling, or "simmering" in the background.
Also, just FYI Ihave about 130+ feet of code 83 Atlas track, currently connected with only one set of feeders and no soldered rail joints. this includes 3 six foot passing sidings and a double ended yard.
The starting current of a sound decoder with the large capacitors is a lot greater than the running current. Turning on 15 sound decoders with a toggle switch would be seen as a short by your booster. Using the amp meter on my Power Cab the current spikes to almost 1.5 amps when starting up a QSI decoder cold,but dies back to under .2 amp in about a half second. Instead of cutting the round house tracks in half you might want to put one or two rotary switches wired to the round house and select one or two tracks at a time. A booster just for the house would be a waste just keeping locos idling. Put your new booster to power half your layout and cut the house tracks when not needed would be a wiser more cost effective solution.
My modular club uses one 5 amp booster for each main line and two 5 amp boosters for all additional track. On large setups there could be as many as 50 locos running on the layout. A majority of them would be idle or switching off the mains. There are usually 3 to 4 trains on each main line running.
Pete
I pray every day I break even, Cause I can really use the money!
I started with nothing and still have most of it left!
locoi1sa The starting current of a sound decoder with the large capacitors is a lot greater than the running current. Turning on 15 sound decoders with a toggle switch would be seen as a short by your booster. Using the amp meter on my Power Cab the current spikes to almost 1.5 amps when starting up a QSI decoder cold,but dies back to under .2 amp in about a half second. Instead of cutting the round house tracks in half you might want to put one or two rotary switches wired to the round house and select one or two tracks at a time. A booster just for the house would be a waste just keeping locos idling. Put your new booster to power half your layout and cut the house tracks when not needed would be a wiser more cost effective solution. My modular club uses one 5 amp booster for each main line and two 5 amp boosters for all additional track. On large setups there could be as many as 50 locos running on the layout. A majority of them would be idle or switching off the mains. There are usually 3 to 4 trains on each main line running. Pete
That is the plan for the new booster. I plan to use it to power half the layout, not the RH. That will put all the locos in one staging yard on a seperate booster which should lighten the load. My thinking is using a switch to take the RH tracks offline when not in use will further lighten the load. I hadn't thought about the sudden spike of suddenly turning on the power to 14 locos at once would have on the system. I'm hoping that dividing the tracks into two seperate circuits will mitigate that problem somewhat. Before I installed the on/off switch to the RH, I was overloading the system so it sounds like it is a matter of picking your poison. If the added booster and additional RH switch doesn't alleviate the overload problem, I'll consider a rotary switch to the RH.
.2 amps for an idling sound loco is rather significant given the size of my roster. With 14 RH tracks, on average, about 10 would have sound. That's a constant 2 amp draw on the system for just the RH. If they spike to 1.5 amps at startup, that's a 15 amp draw on a 5 amp booster. I'm hoping if I can cut that in half with a second on/off switch that the system can handle the brief overload. When I do get an overload, the shutdown isn't immediate. It takes several seconds before it overheats the sensor that triggers the shutdown.
jecorbett When I do get an overload, the shutdown isn't immediate. It takes several seconds before it overheats the sensor that triggers the shutdown.
Your booster should immediately shut down and not a few seconds later. This has me puzzled? Is your buss large enough? Are there plenty of feeders to the buss? How long are your feeders? Have you done a quarter test on the whole layout? Are you using 1156 bulbs for short protection? Is the power supply to the booster too small? Something else is happening here that needs to be fixed before you put more power to the rails.
According to the Lenz manual, there is a thermal safety circuit within the LZV100 which will shut down the unit if there is a CONTINUAL requirement exceeding 5 amps. This seems to say to me the system will shut down only after the thermal safety circuit becomes overheated and I'm guessing that would require several seconds. It doesn't sound to me like a brief spike over 5 amps would trigger an immediate shutdown.
The bus lines are 14G and the feeders are 22G. Except for a few odd places, the feeders are one foot long or less. The bus lines follow the double track mainline fairly closely so it is only in the yards where longer feeders are required. For a few of the longer feeders, I have used 18G. The power supply is an Atlas Generator from my original system. I have never done a quarter test because I have no idea what that is and I do not use 1156 bulbs for short protection. The internal protection shuts down the system immediately when there is a short.
Unless my math is way off, I am quite certain that with just the amps required for the locos at rest, I have exceeded the 5 amp limit of the system and that a second booster is required.
HiIt might be a good idea to put an amp meter in line just to see how much current draw there is at start up and operations. With out this knowledge every thing else is guess work.Good luck
Lee
Yes the Lenz has thermal shut down. If the case is hot to touch than it is thermally shutting down. A quarter test is just shorting the rails at varying locations to see if the booster or breakers will trip instantly. By putting some kind of metallic object like a quarter if the breakers do not trip than you have a problem. Either more feeders, Cold solder joint, or larger buss wires should correct it. There was a video by Joe Fugate that showed how using auto tail light bulbs will reduce layout shutdowns by shorts but I can not find it right now.
Does the output of the Atlas generator have a full five amps continuously? If not than a starvation of power will shut down the booster also. The more load placed on the power supply will thermally shut it down instead of the booster. Our club thought a booster was malfunctioning but it turned out to be one of the magnaforce power supplies that as not outputting the amperage it should have but still read 16 volts DC. When a load was placed on it the voltage dropped and shut down the booster. This malfunctioning power supply was 3 years old. It was young compared to others in use. Also with a failing power supply will not protect your booster from shorts because there is a lack of power to trip the booster. Placing an amp meter in line with your power supply and booster and then between your booster and track will give you an idea if you need more boost or power.
I found it.
http://model-trains-video.com/e107_plugins/forum/forum_viewtopic.php?25
Interesting video. I can see the benefit of the power districts in conjunction with the light bulbs for a club or group operations but for a lone wolf like myself with only two trains max running at one time, I'm not sure it would have that much benefit. Until I began running into the power overload, almost all my shutdowns were due to derailments, usually when passing through turnouts. On the other hand, it might be worth considering. When I first laid the mainline track, I had misunderstood what I had read and thought that each section of track that was connected to a feeder should be electrically isolated from the next section so for much of my mainline, I would have a feeder attached to a soldered joint and the next joint would have insulated joiners. As a result, I already have numerous isolated districts on the mainline. Now the question is whether I want to go to the trouble and expense of putting the light bulbs in line.
I'll try putting an amp meter in line between the power source and booster and between the booster and the track. I can tell you that if I create a short by placing a metal object so it connects the two rails, I get an instant shutdown.
The Atlas Generator's power output is only 3 Amps -- you're overloading it. You need a much heaftier transformer with at least 5 Amps of output.
I recommend this one:
http://www.litchfieldstation.com/xcart/product.php?productid=110013&cat=39&page=1
Drawing too much amperage from the Atlas Generator is what causes other components to overheat and shut down. If the Generator doesn't have an internal thermal circuit breaker, it will continue to function but is probably getting very hot. Overloading it is also creating a fire hazard.
That explains the "short while later". As the Generator overheats, the output voltage drops and eventually gets below the minimum needed to supply the command station.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
rrinker That explains the "short while later". As the Generator overheats, the output voltage drops and eventually gets below the minimum needed to supply the command station. --Randy
Hopefully both problems will be solved when the new booster arrives. I purchased the SZB7-AR from CVP Products, which is a 7 amp booster. This one will be assigned to the section of the layout with the RH which will require the most current. I bought a seperate power supply for it as well which is the one CVP Products recommended for the SZB7, so it should have sufficient power. It comes with a built in autoreverser so I will no have seperate reversers for each of my staging yard loops. With each staging yard in seperate power zones and the more powerful one assigned to the zone with the RH, I believe I should be able to handle the power demands of the idling locomotives as well as up to 4 powered units in motion at one time.
The SZB7-R is a SINGLE booster with autoreverse capability. It cannot power both the main AND provide autoreversing for a reverse loop. With this booster plus your original Lenz you can only have 2 power districts unless you also add circuit breakers like Tony's PSX or the CVP ZoneShare. Better clarify your plans and check the equipment you will need to realize the design.
You will still need a 5 amp power supply for your Lenz booster. Save the Atlas generator for structure lighting or something. Try a 5 amp power supply before you install the SZB7.
When I first installed my Lenz System 100, I used an old Lionel train transformer as my power supply. It appears to put out about 1 amp. Still, I was able to operate multiple locomotives, as many as 3 or 4, with no problem. It was only when I started installing lights in my passenger cars that things went bad. I replaced the transformer with a full 5-amp NCE supply, and I've had no problems with power since.
I have a small roundhouse - 3 stalls, plus 2 outside tracks. I've put each of them on a separate toggle switch for power. When an engine is in there, it is shut down and it's not powered up until I'm ready for it. Not only does this prevent the big power surge at startup, it also gets rid of annoying "extra" sounds from the not-in-service locomotives. I would recommend individual toggles for each stall. In your case, with that many stalls, you might consider a rotary switch.
It takes an iron man to play with a toy iron horse.