Product Support for: Power Management -> PM4 to PM42 Upgrade kit (PM42 UPGRADE)

What's the difference between the PM42 and the PM4?The PM42 is an improved version of the PM4. We added 2 faster short circuit detection sensitivity settings and revamped the manual. Get the benefits of short circuit management and auto reversing without adding more boosters! PM42 Quad Power Manager lets you use a single booster and divide its output into 4 power sub-districts for automatic reversing &/or to improve operation by preempting booster shutdown when a short circuit is detected by the PM42. If you want to improve operation but don't need the added power (or expense) of adding a booster, ...

Use a throttle to change the PM42's Option Switches 01, 02 and 09 as detailed in the PM42 instruction manual. The PM42's trip current threshold can be set at a value from 1.5amps to 12 amps. Always use the lowest possible setting, consistent with good operation and reliable short circuit detection and recovery. Higher current settings are not "better." We ship the PM42 with a moderate current trip threshold of 3amps so it will work on most DCC boosters and layouts with no changes.This is because some boosters cannot supply enough current with the track feeder resistance to reliably allow ...

Q: I have an older Super Chief system that came with DT100 throttles. They are both shot; one was accidentally pulled apart by an over zealous operator who forgot about the cable length and the other was ruined by me (I'm ashamed to admit) by spilling some super glue on several of the buttons. Can I upgrade to the current throttles or do you recommend I purchase the old DT100 units? A:  All Digitrax Starter Sets have LocoNet, including your older Chief series unit. This means that you can use any Digitrax throttle past and present.  Both of your damaged DT100 ...

Can a UR91 be returned and upgraded to a UR92? No. Our recommendation is that when upgrading to the DT402 throttle, the layout owner purchase a new UR92, but keep the UR91 installed for those who still have the simplex radio throttles. That way anybody can run on the layout.

Q:  Can two sections of a single PM42 be configured to perform both the task of a circuit breaker and also automatic reverse section control for a single reverse loop? The PM42 can be configured so that one section of the PM42 is used for circuit breaker operation, feeding into another section of the same PM42 which is configured for automatic reverse section control. In the field, this configuration has been found to be unreliable in some layout configurations.  If you are having problems getting this to work in your setting, we recommend using an AR1 to handle the automatic reversing secion.  The ...

On Page 9 of the instructions (under 5.0 Op Sw Set Up) I am to connect my DT400 throttle to my powered PM42 . . . 1. Does “powered” mean having the PS-14 power supply to the PM42 connected and energized? Yes. We took another look at the documentation and it means that the PM42 should be operating with its own power supply. What you are doing is using the DT400 to program the internal controls of the PM42; to do so would require that the PM42 be in its operating state, thus the power supply. The DT400 is merely ...

Q:  How do I program the PM42 Option Switches (OpSw) with a DT400 throttle? A:  The PM42 OpSw settings are used to set up the PM42, adjusting the trip current, short circuit management (including sensitivity), and/or auto-reversing. Note: The factory default setting on all PM42 OpSws is “thrown” or “t”. Follow the steps outlined below to program the OpSw settings of the PM42 using the DT400 series throttle with any Digitrax command system. 1) Connect the PM42 to a DCS50, DCS51, DB150, DCS100, or DCS200 with a standard LocoNet cable. 2) Connect the PM42 to an external power source; Digitrax ...

  Q:  What is the basic configuration and Option Switch (OpSw) settings for each of the four sections of the PM42 when configured for automatic reverse section control? A:  The PM42 is a 4 section multi-purpose device where each of the four sections can be individually configured to act as either a circuit breaker, or auto-reverse section controller or DPDT relay. When configured as an auto-reverse section controller, the PM42 adjusts the rail phasing of the reversing section it controls whenever a locomotive, or car with metal wheels, bridges the gaps between the rails of that reverse section and an adjacent non-reversing section ...

Q: What is the basic configuration and OpSw settings for a section of the PM42 when configured for circuit breaker control? A:  The PM42 is a 4 section multi-purpose device where each of the four sections can be individually configured to act as either a circuit breaker, or automatic reverse loop controller. The PM42 monitors the current flow to the rails and interrupts the connection when it senses that the current demands exceed the upper allowable current level determined by the User controllable Option Switch (OpSw) settings. The power flow of a layout's command control system starts with the command station, or ...

The installation instructions indicate that a PS14 be used to power the PM42. Is it necessary that I cut the wire from the PS14 so that is can be attached it to the 44-pin connector, or is there a male adapter available for the connection? Yes, currently you will need to cut the wire, strip the ends and solder them to the edge connector of the PM42. Please see the related articles below. Which lead from the PS14 is to be soldered to terminal 3 on the 44-pin connector and which is to be soldered to terminal C? The PM42 ...

The PM42 was specifically designed to work with Digitrax Direct Home wired layouts. Any system that is configured this way will work with the PM42 with no interoperability issues. For example, CVP uses interoperable booster connections.The PM42 can be used with a DC system if it is hooked up in the negative ground return path, or even a Marklin AC digital (trinary) booster. It is possible for the PM42 to be used with most DCC systems. Digitrax has no control or knowledge of each specific non-Digitrax system and how it may interact with the PM42.

  Q:  Can I use a PM42 with a non-Digitrax DCC Command system? A:  The PM42 was specifically designed to work with Digitrax Direct Home wired layouts. Any system that is configured this way will probably work with the PM42 with no interoperability issues. Digitrax has no control over or knowledge of each specific non-Digitrax system and how it may interact with the PM42. The PM42 can be used as a stand-alone auto-reversing unit and short circuit manager with many third party DCC systems, but for systems without LocoNet capability a number of the networked management features will not be available. ...

  Q:  How do I program the PM42 Op Switches with a DT300 throttle? A:  The PM42 OpSw settings are used to set up the PM42, adjusting the trip current, short circuit management (including sensitivity), and/or auto-reversing. Note: The factory default setting on all PM42 OpSws is “thrown” or “t”. Follow the steps outlined below to program the OpSw settings of the PM42 using the DT300 throttle with any Digitrax command system. 1) Connect the PM42 to a DB150, DSC050, DSC100 or DSC200 with a standard LocoNet cable. 2) Connect the PM42 to an external power source; Digitrax recommends the ...

  How do I program the PM42 Op Switches with a DCS50 (Zephyr) throttle? The PM42 OpSw settings are used to set up the PM42, adjusting the trip current, short circuit management (including sensitivity), and/or auto-reversing. Note: The factory default setting on all PM42 OpSw's is “thrown” or “t”. Follow the steps outlined below to program the OpSw settings of the PM42 using the keypad of a Digitrax Zephyr. 1. Connect the PM42 to the Digitrax Zephyr with a standard LocoNet cable. 2. Connect the PM42 to an external power source; Digitrax recommends the PS14. Note: Before entering Switch Mode ...

Can I combine the power input requirements for PM42's with other units for economy?Digitrax recommends each PM42 module to have its own seperate power source. The criteria for choosing a power supply for the PM42 is any power source that can deliver 12-15V AC or 13.8-15V DC with a minimum of 125 ma. The Digitrax PS14 meets the minimum power requirement of a PM42.It is possible to power more than one PM42 from a single power source. When powering multiple PM42's special care must be taken to insure identically phasing of all PM42's and ample current availability to power all ...

When I get several locos in the same PM42 sub-district, the PM42 seems to shutdown at random times even though I am sure there is no short circuit, what is wrong?1.  The PM42 is set at the factory with a default current trip point of 3 amps for all 4 sub-districts. This is fine in most cases. 2.  If you plan to run more than two or three locomotives in a sub-district, you will need to increase the trip current. 3.  Use the minimum current set point that gives acceptable layout operation, i.e. minimum power interruptions when no short circuits ...

Q: If my layout is experiencing short because of a thrown switch, how can you reset the switch using DCC? Many Digitrax operators use the PM42 Power Manager, which provides protection to four power sub-districts. One segment of the PM42 is used to control track switch power, with the balance being used for train power. When the inevitable happens and a train runs into a thrown switch, resulting in a short, the PM42 shuts down the track power in that segment, while the track switch power is maintained, allowing you to throw the offending switch. Because the PM42 isolates only ...

If I use a non-Digitrax compatible system, what features of the PM42 Auto reverse/Short Circuit Managers (SCM) will I lose?The PM42 can be used as a stand alone Auto reversing unit and Short Circuit Manager with many other non-Digitrax systems, but for systems without LocoNet capability a number of networked management features will not be available.For example, the PM42 sends out real-time, event driven (non-polled) information to the LocoNet about fault problems and resolution, auto reverse actions and also identifies the affected sub-districts. This allows other devices, such as PCs, the Digitrax Signaling system, Digitrax Transponding or other detection and ...

When changing the board address of the PM42 to say Decimal 20, what is the switch number to put the PM42 section A into auto-reverse? The default is 6. To set Section A of a PM42 to auto-reverse, you set OPTION SWITCH 6 TO "c" no matter what the board address is.

When using the your PM42 with an AR1 Auto Reversing controller do not use the "fastest setting" in the Short Circuit Sensitivity Settings section:

My PM42s seem to correctly trip on track shorts and auto-reverse reliably, but the power briefly drops out during these events, and when the PM42s attempt a fault recovery into a persistent short circuit, why is this?No power on earth can stop the track voltage of the booster from collapsing to a low value when a true short circuit is present. This is simply Ohm’s law in action!Actual track voltage seen depends on: the loop resistance of the short circuit, the current capacity of the booster and power supply and whether the Booster employs "smart" fault detection and recovery along ...

Is it possible to configure the PM42 for auto reversing without a Digitrax throttle? We're accustomed to working in the Digitrax operating environment, so our answer is theoretical at best. However, it would seem that any operating software with a LocoNet interface could be used to set the PM42 address, using the software as a throttle in this situation.

My dealer told me that the when the PM42 changes polarity on a section of track, that it should remain that way till another "short" is detected. Mine will change polarity for about 1 - 1.5 seconds and then change back. Is this normal and my dealer told me wrong? Your dealer is correct. You may need to adjust the trip timing of that particular node of the PM42.

  Can the AR1 or PM42 be used to power the track of a turntable? This track section would be electrically isolated from the surrounding tracks which would all be powered from the same booster. Yes. A good number of our customers use either the AR1 or one node of a PM42 to handle turntable powering issues.

How can I remotely monitor the input and output status of a section of the PM42 that is configured to act as a circuit breaker at a remote location? The final output stage, of each section, of the PM4 or PM42 is a DPDT relay. The contacts of this relay act in a similar fashion as the contacts of a DPDT toggle switch. These inputs and outputs can be monitored in a variety of ways. Three common monitoring devices are a LED (with appropriate resistor), a lamp (of the appropriate voltage), or an optical coupler (with appropriate resistor). The following ...

  Do you have a recommend wiring procedure for the 44-pin edge connector on the PM42 and SE8C?PM42, PM4, BDL168, BDL16, BDL162 & SE8C use a 44-pin edge connector. Connecting wires securely to this connector requires soldering skills. For connections to the 44 pin connector, Digitrax recommends using 16 gauge stranded wire. For all other soldering connections, Digitrax recommends 14 gauge (AWI) stranded wire for electrical connections on your railroad. 1. Use individual short lengths of 16 gauge wire to connect to the 44 pin connector. 2. Strip and tin both ends of the wire. 3. Bend one end into ...

Q:  What is the preferred way of protecting a reverse loop with circuit breaker management and still having automatic reversing? A:  There are two ways of protecting a reversing section with a circuit breaker and reversing section controller. 1.  Use one PM42 (circuit breaker manager) and one AR1 (automatic reversing section controller). 2.  Use two PM42s (one as a circuit breaker manager and one as a reverse section control). The following diagram displays both methods: a) The first method (left), is where one section of a PM42 configured for circuit breaker operation feeds one or more AR1s (automatic reversing section controller), or b) The second method ...

44 pin connectors with screw terminals were originally designed by a company called LWH3.  Their products allow you to install the PM42, BDL168, and SE8C without having to solder to the 44 pin connector.  The product line was sold to Accu-Lites.  These products are available online directly from Accu-Lites at www.acculites.com              

PM42 Short Circuit/Auto-Reversing Failure When used with Zephyr (DCS50) The PM42 is designed to control 4 independent power subdistricts that can be set up as either a “Short Circuit Manager” (the factory setting) or as an “Auto-Reversing Controller.” The PM42 factory setting for trip current is 3 amps. The trip current can be modified to settings from 1.5 amps – 12 amps to accommodate the needs of your system. In addition, each of the 4 power subdistricts can be set for slow, regular, faster or fastest short circuit management. While a trip current of 3 amps will work with most ...

Problem: PM42 Short Circuit/Auto-Reversing failure when used with Zephyr (DCS50/DCS51)The PM42 is designed to control 4 independent power subdistricts that can be set up as either a “Short Circuit Manager” (the factory setting) or as an “Auto-Reversing Controller.” The PM42 factory setting for trip current is 3 amps. The trip current can be modified to settings from 1.5 amps – 12 amps to accommodate the needs of your system. In addition, each of the 4 power subdistricts can be set for slow, regular, faster or fastest short circuit management.While a trip current of 3 amps will work with most boosters, ...

Q:  I just purchased a used Digitrax set consisting of a DB150, UT2 and a PS515 for a very low price. What do I need to add to bring this up to current standards? A:  Because of Digitrax LocoNet, it is easy to add the latest components to upgrade on older starter set.  What you purchased was originally called a Genesis Starter Set.  The PS515 did not come with it but it is the perfect power supply for the DB150.   Your next step depends on what you want to do with your railroad.  In this case, the components you have will be ...

Get the benefits of short circuit management and auto reversing without adding more boosters! PM42 Quad Power Manager lets you use a single booster and divide its output into 4 power sub-districts for automatic reversing or to improve operation by preempting booster shutdown when a short circuit is detected by the PM42. If you want to improve operation but don't need the added power (or expense) of adding a booster, the PM42 is the right answer for you. Each PM42 can run 4 sub-districts off a single booster in any combination of regular sub-districts and auto reversing sub-districts.

Q:  If you buy the infra ready set and down the road want to upgrade to the radio is it necessary to buy a whole new set? If not what is required to upgrade the existing set? A:  The DT400 or DT402 can be converted to DT402D duplex radio or DT402R simplex radio.  The conversion must be done by Digitrax. If you plan on using the IR features of the DT400 or DT402 , you will need one or more UR90 infrared receivers.If you convert the DT400 or DT402 to duplex radio, you will need a UR92 duplex transceiver which handles both infrared ...

As originally conceived, the Texas & Southwestern was set up with a very simple DCC system. The railroad uses a DCS50 Zephyr as its command station and booster. The Zephyr is connected to a central power bus, and all tracks, stationary turnout decoders and the automated reverse loop unit are connected to it. Likewise, the LocoNet connections are a series of simple cable connections starting at the Zephyr and ending at the last Universal Panel. The T&SW works well with this arrangement, but there are additional devices that will enhance the operation of this railroad. Digitrax PM42 Power Management System ...

Do I need an additional booster if I run isolated sections through a PM42 or can I use one Zephyr?  This is a small layout design (5X9) and looking to make it as simple and safe as possible.This is really a question of how much power your railroad requires.  You don't state what scale you are operating in, so a 5x9 in H0 might only have three or four locomotives, while a 5x9 in N-Scale might have fifteen or twenty locomotives.Initially, you will be making an estimation based upon your power requirements and the output power of the 2.5 Amp ...

Q: I have the original DCS100 with the old style non-removable wire connectors. What would I gain with a firmware upgrade? A: Early DCS100s that do not access Functions 9 - 12. If you have a DCS100 that you would like to have updated, please send it to the Digitrax Repair Department for updating. This update is a chip change only and the original style connectors will not be changed to the new style connectors. The circuit boards used for the two different connectors are completely different and are not interchangeable. The DCS100 must be sent to us for this ...

I'm helping a friend rewire an existing layout from analog to digital. You might be familiar with the layout, it is the original Clinchfield layout that Model Railroader built back in the late seventies, believe it or not. The layout, of course, is blocked for analog through DPDT switches which have been eliminated. I was able to repair the wiring back to original using the drawings that MR printed. The layout uses common rail wiring, this is what I have to work with, and to rewire using home run wiring would be a MAJOR rework, not doable. I was able ...

We have designed a layout at my place with double main line with reverse loop at each end. Plus there is a branch line with two reverse loops that in one loop is connected to the main line. The main lines stay double track even at the split. The branch stays single with only one connection with the main. My plans where to use the AR1 for all my reverse loops and the PM42 for my power control. What if any problems do you see with all these loops? Nothing, if you can guarantee that at any given time only ...

  Q:  Can I mix UP-5s with Radio and IR panels? I want to upgrade slowly and still use the 400 throttles and the UT throttles while I mail them in to you one at a time for conversion to radio. A:  Yes, and you can continue to use the UP5's after conversion to radio; for instance, if you have visitors who bring their own Digitrax non-radio throttles. That's the real genius of LocoNet, since you can add to your railroad in any way. Note that you will need to plug in your throttle to LocoNet initially to select the locomotive before you ...

Although this is a simple railroad, it will have some advanced features. When the railroad's sectional modules are first assembled, the electrical connections are simple. The railroad will be controlled with a DCS50 Zephyr, using a PM42 Power Manager for short circuit protection. One section of the PM42 will control the inner oval of track, a second section of the PM42 will control the outer segment. This is done so that if a train derails on one loop, the train operation on the other loop will not be affected. Because the DCS50 is rated at 2.5 amps, the PM42 must ...

Power Management is a concern on every layout.  With Digital Command Control, the main concern is that enough power is supplied to evey track section on the layout so that the digital signal is transmitted to the decoders in the locomotives and turnouts.Each locomotive uses power from the track, some for the motor, some for headlights and other functions and some for the command control electronics in each locomotive.  More electrical power is necessary to run more locomotives on the layout.  Digitrax boosters provide between 2.5 amps & 8.0 amps.  A small N Scale or HO Scale layout with two to ...

What is the difference between boosters and power management? A Booster is the device that provides the electrical power to the railroad. Most Digitrax command stations have a combined booster. The command station generates the DCC signal then sends it through a booster to the layout. A small model railroad may only have the command station and booster, while a large railroad will have numerous boosters. Multiple boosters provide more power to larger layouts.Additional boosters receive the DCC signal from the command station via LocoNet. Power management usually refers to the devices which act as circuit breakers and power distributors. ...

How to disable command station capability in a DCS51 (Zephyr Xtra) or DCS50 (Zephyr) so it will operate as a booster and throttle without command station capabilityIf you have outgrown your Zephyr Xtra or Zephyr and have moved up to a more powerful command station, you can disable the command station capability in your DCS51 or DCS50 and continue using it as a booster and throttle in your system.Digitrax operators who upgrade from Zephyr to more powerful command stations for their systems can change Zephyr into a Booster/Throttle by setting OpSw 02 to closed. Changing DCS51/DCS50 Option Switch 02 to closed to disable command station capability: ...

The PM74 OPSW41= C will change the 4 DS1-4 led display, so each DS led now reports the same way the PM42 leds did. This is a Legacy option provided for users who want the PM74 indications to be similar to the PM42. The default OPSW41 =T has the DS led light ON for resistance Occupancy detection within that DS, and will flash when a Transponder is present in that DS. These 2 additional DS detection capabilities and indication were NOT present in the PM42. Whatever the OPSW41 state is, LocoNet messages will report Power state/action,  Occupancy and Transponding messages to a connected LocoNet, ...

Is it possible to add a pair of PM42 Power Management Modules between the command station Rail A/Rail B outputs and run the resulting output from the PM42's on as many as 8 sets of Rail A/Rail B Wires to 8 isolated power Zones? These isolated power zones could have their Common Zone (Rail A) Wires running through RX1 transponding receivers connected to an RX4 ribbon cable running to the BDL168 for the purpose of interfacing with the SurroundTraxx Multi-Train Sound System. If this is possible, it would only require 5-6 of the DS lines on the BDL168 to be ...

I am building a layout that will have two completely separated track plans; not connected with each other by any track. I am running one layout with a Super Chief that has one AR1 reversing controller.  I would like to run the second layout with the same throttle. It will have a reversing loop, as well as a turntable.  I have thought that I could run the second layout with a booster and a couple of AR1s or PM42.My questions is, will I have any problems with the reversing loops, especially if one on each layout is triggered at nearly ...

  I have a 14x24 foot room with a shelf layout on two levels. 1st level is about 24 inches with two main lines and some industries, a moderate freight yard, moderate intermodal facility and passenger station. The second level is 18 inches and will contain one and two main lines with mostly industries. This would qualify as a "medium to large" model railroad. I would like to have 1-5 operators with 2-10 trains running at one time as permitting. At least four Universal Panels would give all operators full access to LocoNet as necessary. At least one UP each ...

The BDL168 is designed to be used with power management devices such as PM42. The BDL168 is designed to operate “downstream” of the Digitrax boosters and power management devices. The BDL168 is the "last" device in the chain from booster to power manager to BDL168. It is connected directly to the track detection section. There should be no other connections to any detection section that will draw track power or the detection section will always show occupied. If a device is used to switch off power feeding the BDL168 and the track it is connected to, for example, a PM42 ...

I have multiple reversing districts, do I have to buy a separate booster for each one?You can run more than one reversing district off a single booster, but there is the potential problem that might arise is if you have more than one set of wheels crossing more than one set of gaps at the same time. In this case, the booster will detect a short and shut down (unless the polarities just happen to be matched up in which case you won't see a problem). We recommend that you use the AR1 Auto-Reversing unit or the auto-reversing capability of the ...

My question is: How do I mount the PM42? Do I need a special housing in order to mount it under table? It appears to me that mounting it flush against a surface would prevent, or make it extremely difficult, to attach the 44-pin connector. Digitrax manufactures three devices which have a 44-pin connector. These are the BDL168 (and its predecessor the BDL16), the SE8C and the PM42 (and its predecessor, the PM4). These best approach to mounting these devices is to screw the connector directly to the wiring panel board. Drill mounting holes in the end of the 44-pin ...

I have read that the amperage of the power supply should match the amperage rating of the booster / command station. Yes, from the standpoint of putting more than 8 Amps of power into an 8 Amp Chief is not going to make a difference since only 8 Amps is going to come out. Less than 8 amps in is only going to result in that same amount (roughly) out; thus, a 5 Amp power supply will only yield 5 Amps out, even though the system is rated at 8 Amps. The DCS200 Super Chief is rated at 8 amps. ...

  I have an "M" shaped 250 square foot layout with 500 feet of track and twelve locomotives. What Digitrax equipment would I need? You don't say what scale this railroad will be modeled in, which is important since the locomotives in smaller scales draw less current than larger decoders. However, for purposes of estimation: Twelve Locomotives. Each locomotive is going to draw, at the very least, 5 MA for the decoder. If it has LED lights, then it will typically draw 15 MA more; conventional light bulbs will draw 50 MA. A typical H0 locomotive will draw 600 MA ...

The answer to this question applies to all Empire Builder sets including Super Empire Builder XtraQ:  I have just purchased a Super Empire Builder set. My expectations are for it to operate an N-Scale switching layout right now with future expansion to a larger N-Scale layout. I am a little confused as to which power supply I would need at this time. I am reading about power supplies and inline fuses, all of which is a little overwhelming to me as I am getting back into the hobby. Can you recommend which power supply will be better for me as ...

What do I need for DCC control of a Walters Cornerstone Swing bridge? Image Courtesy Wm. K. Walthers We do not have any direct experience with this particular bridge but after a little research, this is what we recommend.The instruction sheet which comes with the 933-1050 Motorizing Kit is quite vague.  "The unit runs on DC power.  Hook the wires up to the DC contacts on a transformer with a maximum voltage of 12.  If you hook it up to a variable speed transformer, do not exceed 12 volts.  The gear ratio is 320:1."  That said, it is still a ...

Adding duplex radio, infrared or simplex radio to your existing Digitrax system is simple because of LocoNet.InfraRedYou probably already own a DT300, DT400, UT4 or DT402 series throttle. All of these are "InfraReady." These all come with two IR emitters pre-installed. All you have to add for IR operation is one or more UR90 Infrared Receivers to your layout. Most layouts require multiple UR90s because the infrared signal is line of sight. This means that your receiver will need a sight path to the throttles.Simplex RadioDigitrax throttles with an "R" at the end of the part number are simplex radio ...

Digital Command Control (DCC) has specific electrical requirements that must be provided for your layout control system to operate properly.Input PowerAll DCC systems require an external power supply.  Digitrax manufactures several power supplies for our command stations and boosters: The 3 Amp PS415 (the Zephyr Xtra power supply) The 5 Amp PS515 for all Digitrax 5 amp command stations and boosters The powerful 20 Amp PS2012 can be used for multiple 5 and 8 amp command stations and boosters  Additionally, the PS14 is available to power various other devices for your railroad.  Digitrax strongly encourages you to use our power supplies to insure satisfactory ...

This H0-scale railroad track plan first appeared in the Atlas Model Railroad Company's book "Six Railroads You Can Build", written by John Armstrong and illustrated by Tad Stepek. This book was first published in 1958 and has been reprinted several times. A classic bowl of spaghetti, the Transbay Interwoven has two reversing loops and a turntable. DC Control For DC operation, Atlas specified three Atlas Controllers (for the reverse loops and the turntable), two Atlas Selectors (to control eight track segments) and ten controllers for the railroad's turnouts. DCC Makes Things Simple With DCC, the wiring of this railroad is ...

I am putting the finishing touches on my 10 x 20 foot H0 railroad. It is a copy of the Cajon Pass, Salt Lake & Santa Fe RR by John Armstrong (#86 in the 101 Track Plans by Linn Westcott) [Kalmbach Publishing, ISBN 0-89024-512-6; still in print]. I have decided to go with DCC and my local hobby store recommended Digitrax. The layout is in my basement, I will be the only operator, the plan has 54 track switches (34 NJ International twin coils and 20 Tortoise turnout motors). Can you give me an idea as to what equipment I ...

  This document outlines the power requirements for Digitrax LocoNet accessories.  To simplify wiring, Digitrax recommends providing individual power supplies for like accessories.  For example a power supply or power buss which only powers the PM42s.  A power supply or power buss used solely to power multiple DS64s.  UR9x and UP5 panels can be daisy chained provided adequate current is provided to properly power all the panels.  Through the use of individual power supplies, the chance of Ground Loops or sneak paths back to ground is minimized.  Using individual power supplies will also make troubleshooting much easier.  Many Digitrax LocoNet ...

DCC Automatic Reversing SectionsVirtually all automatic reversing will fall into 3 categories with the wiring principles for all being the same:1. Reverse Loops2. Wyes3. TurntablesDCC has the ability to automatically reverse sections of track we call Reversing Sections while our trains are running and not affect the direction or speed of the trains. This is because we put a constant square wave AC current on the track and control the trains (locos) by sending messages to them (actually to receivers we call decoders) to tell them what to do such as start, stop, change directions, etc. . We are thus ...

Since many Zephyr and Zephyr Xtra Starter Sets are used on smaller railroads, a natural choice for setting up an automatic reversing section would be an AR1. If you have more than one reverse loop, then the PM42 is a better choice. These automatic reversing strategies will work equally well for any Digitrax system using any Digitrax Starter Set.  Alternately for larger railroads, an auto reversing booster such as the DB150 can be used for automatic reversing if the section is large.

Am planning a 4 district layout with a Super Chief set. Can I serve all 4 districts with it using circuit breakers for each district? If not what do I need?In this case, the PM42 quad power manager can be used to give you circuit breakers in each of the 4 sub-districts.

I have a medium/large sized layout with a reversing district. I want to operate 6-10 trains with several operators. I am interested in turnout control, prototypical consist operations and signaling to be added later. I might want a computer added later, too. Which components do I need?You will need a Super Empire Builder Xtra or Super Chief Xtra with additional throttles for the operators and an additional DB150 booster or PM42 for the reversing district. You will also need at least one additional DB150 to provide enough power to run 6-10 trains in N or HO. You can choose and Digitrax ...

Q:  How do I wire a double crossover? Each crossover results in a reversing loop. Should I use a PM42 or AR1? This is O scale (2 rail) if that would have any bearing on your answer. A:  Without a drawing to see how things are laid out, this can only be a guess, but a couple rules do apply. The reversing sections must be longer than the longest train. And there should be only one train in the reversing section at a time. It also seems to be a good idea to keep the reversing sections away from the ...

Digitrax auto-reversing units such as the PM42 or AR1 require a "hard" short for them to work properly, which means there must be good current flow to both sides of the gaps, on the reversing section side and on the "normal" side.  For this reason it is poor practice to put the gaps immediately behind a turnout relying on the points of the turnout to supply the current to the "normal" side of the gaps leading to the reversing section.  Resistance through those points often reduces the current to where a good short cannot occur preventing the auto-reversing unit from ...

The DB200+ is the 8 amp booster. It has NO command station capability. This booster was designed for adding power to layouts that run lots of locos and for large-scale layouts where power requirements are heavy.DB200+ Control PanelNOTE: DB200+ front panel graphics may vary from those shown here.  Internally the booster is the same. These instructions are written for both versions of graphics as well as the DB200+ OPTO optoisolated version of the booster. About the Green Jumper WireEvery DB200+ is shipped with a green jumper wire on the front panel Booster Terminal Plug connecting Synch & Ground or ‘Config ...

Problems occurring on most auto reversing sections are a result of improper wiring or gapping. Digitrax auto reversing units such as the PM42 or AR1 require a "hard" short which means there must be good current flow to both sides of the gaps, on the reversing section side and on the "normal" side. Our experience has been that over 90% of reversing section problems are a result of improper wiring or improper gaps. Another 5% is a result of improperly wired or configured auto reversing units. It is poor practice to put the gaps immediately behind a switch (turnout in ...

Many clubs use a DCS100/200 as a Booster in their setups.  Digitrax does not recommend using a DCS100/200 as a Booster only for this type of setup.  If you decide to do so, please keep this information in mind:   The DCS100/200 configuration is stored in memory that uses a CR2032 battery.  Over time the battery can get weak and the DCS100/200 will loose its ability to store its configuration.  When this happens, the DCS100/200 will sound 7 beeps at power up.  It will also revert back to its factory settings and once again become a Command Station.  Since LocoNet ...

Q: I am building a new DCC layout that will include a logging spur that is simply a single long piece of track with no loop. I want to have a train go back and forth on this track which automatically reverses when it gets to each end. While the AR1 was designed for reversing loops, can it be wired to simply reverse a train on a straight piece of track? A:  Not in the way that you intend. One of the interesting problems with DCC is that we often still think in terms of DC, where the track polarity ...

The slip switch is a track element that has both a crossing at grade and also a set of movable points which allow trains to both cross another track and also change track.  The Crossing The crossing allows tracks to cross each other at grade.  The Slip SwitchThe more complex slip switch allows trains to both cross and to change tracks: In the schematic below, you will note that the slip switch is more compact than ordinary turnouts.  As a result, they are often found in high track density areas such as passenger terminals, where space is at a premium. ...

I was planning on purchasing the Digitrax Super Chief Radio 5 amps but several members in the club told me to buy them Super Chief Radio 8 amp for my HO Layout.  They said you will need the power when you start expanding.Question:Is it ok to use the 8 amp version for my HO layout?Answer:Yes it is fine to use 8 amp Digitrax boosters on your HO layout.  The choice between 8 amp and 5 amp command station/boosters, it is a question of how much power your railroad is likely to consume on your railroad as it is built today.  ...

What is it and how do I find a DPDT?It's an electrical switch; double pole - double throw (DPDT). Here is a schematic of a DPDT: More typically, they look like this: The DPDT is very common to model railroading and found at just about any store that sells electronics.  It comes in a variety of arrangements, with the most common being a DPDT Center-Off switch.  Analog OperationsIn the early days of Direct Current model railroading, reverse loops had to be controlled by hand, and the DPDT was perfect for the job.  The DPDT was wired in such a way ...

Before sending your Digitrax Command Station or Booster in for repair try these simple steps to see if you can “bring it back from the dead” and save a possible trip to the repair shop.1. Nothing is respondingIf there are NO LEDs lit on the front panel of the Command Station or Booster: Check the power supply to the unit to make sure that it has not been knocked loose in the power socket and that the socket is powered. Check the connections from the power supply to Track A and Track B connections on the front of the unit ...

Q:  I am not sure where to begin. Dabbled in O & HO over the years and am now starting into S but have no knowledge in DCC. My layout is drawn, Dog Bone, with an over size of approx 20' by 11'. As of now there will be 8 turnouts and perhaps a turn table will be added or more turnouts. My intent is to run maybe 3 or 4 engines max. My only purchase so far is a Showcase Western Maryland, scale, which includes DCC with sound. My next comment is HELP! I do have a 2006 Summer ...

Q:  I am the only operator. There will be no others. I wish to use block detection for signaling. However, I find that I cannot use the BD4s in the way I thought they could be used. My question, must I divide my simple layout into blocks (which DCC says you don't really need) in order to use the BD4's and SE8C together? A small basic layout can be operated in the DCC environment without dividing the railroad up into power districts.  In this scenario, you will use one command station/booster to power the entire layout. As your power consumption ...

In earlier generations of model railroading, the reverse loop (reversing section) was the bane of many model railroaders. As the rails of a track come back upon themselves, an electrical short circuit is created. In the analog control world, the solution is to use toggle switches and special wiring to allow the locomotive to move on to the next block. Electromechanical solutions relying on relays and track detectors can also be used to automate reversing on an analog layout. The wye is another example of a reversing section on a layout. One of the advantages of digital command control is ...

BD4 Output Each BD4 is situated between the PM42 Power Manager and the railroad. The DCC signal passes from the DCS50 Zephyr, through the Power Manager, through the BD4 to the track to the locomotive. When a locomotive (or equipped car) is present in a track segment, the BD4 also sends out occupancy information, in two ways. Occupancy Information Output LED1 The LED1 10-pin header is for testing the status of power to the rails and block occupancy with the LED indicator which is included with the BD4. The LED1 can also be used for panel indicator lights using LED's. ...

Here are some terms that you might find useful as you work with the BDL168. Direct home wiring is a layout wiring method where each power district and its booster is electrically isolated. The track within each power district uses a "common return" wiring method for occupancy detection and/or power management. Direct home wiring is the wiring method recommended by Digitrax for safety reasons & also because it makes detection work more prototypically. Power district is the power wiring, track, components and equipment attached to that wiring, driven by a single properly isolated booster. The track for a power district ...

Digitrax Complete Train Control By Zana & A.J. Ireland Digitrax Complete Train Control makes reliable, realistic train operation and simplified layout wiring a reality. Digital Command Control is incorporated within the Digitrax system to let you control multiple trains independently on the same section of track without blocking. In the real world, engineers control the speed and direction of real trains. Engines operate under their own power independent of the track. Each engine has its own motion characteristics like how fast it speeds up (acceleration) and how long it takes to slow down (deceleration). A locomotive's performance is influenced by ...

I have a 4x8 H0 scale layout.  I'm 13 years old and REALLY thinking about switching to DCC, I need to know really fast because I want to ask my parents to get it for Christmas.You wouldn't know by looking at those who edit the Tech Support Depot, but there actually was a time when we too were thirteen, and just starting out in model railroading.  In many ways, we still are thirteen years old; we just can't move as fast.  Consider this photograph from our youth: This little bit of ancient model railroad history dates back to the 1950's, ...

By Zana & A.J. IrelandThis clinic is titled Digital Command Control: The Wave of the Future. Recently, I was asked the question: "DCC has arrived and is the technology of today, everybody's using it so, why don't you change the title of your clinic?" My answer is that digital command control is still evolving rapidly. Today's digital command control is moving beyond the basic NMRA DCC Standards and RPs to encompass many new technologies that will compliment and enhance the basic things we can do with the track format defined by the NMRA. It's an exciting time for model railroaders ...

By Zana & A.J. IrelandThis clinic is titled Digital Command Control: The Wave of the Future. Recently, I was asked the question: "DCC has arrived and is the technology of today, everybody's using it so, why don't you change the title of your clinic?" My answer is that digital command control is still evolving rapidly. Today's digital command control is moving beyond the basic NMRA DCC Standards and RPs to encompass many new technologies that will compliment and enhance the basic things we can do with the track format defined by the NMRA. It's an exciting time for model railroaders ...