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NCE Smart Booster (SB3)




  1. (1) Digitrax PS315 3A/15VAC wall transformer (purchased separately)

  2. (1) 4-port power/track connector (black)

  3. (1) 3-port Control Bus connector (green)

  4. (1) NCE Smart Booster

  5. (1) 6-page NCE Smart Booster manual containing information/explanations on the following sections:


  • Power Supply

  • Short Circuit protection (with diagram)

  • Connecting extra boosters

  • Layout wiring (with diagrams)

  • Specifications

  • Available connections

  • Indicator lights

  • System limits of SB3 with Power Cab

  • Resetting (rebooting) the System

  • Returning the system to original factory settings

  • Changes from Power Cab V. 1.10

  • Advanced Layout Wiring (diagram)

  • Accessory equipment available

  • CP6 Hook UP with an SB3 system (diagram)


Initial thought and impressions


I purchased and received both my NCE Smart Booster (SB3) and Digitrax PS315 3-amp - 15VAC wall transformer from Empire Northern Models.  Everything was well packed and protected.


As mentioned above, the SB3 comes with its own 6-page manual.  I thought NCE did a very good job of explaining how to set up and use your SB3.  I also thought the manual was straightforward and easy to understand - especially with a good use of diagrams for explaining the proper wiring of the unit to the layout.  One nice bonus is a diagram for showing you how to easily hook up an automotive tail light to your SB3 to use as an external short circuit protection device.


After opening up each of the boxes, the first thing that jumped out at me was the physical size of the 3-amp wall transformer.  At 3-1/4"H x 2-1/2"W x 2-1/8"D, this "wall wart" was almost as large as the SB3 itself - and a lot heavier!


The second thing that I quickly noticed was the introduction of additional ventilation holes on the enclosure of the SB3: (3) at the top and (4) on one side - which weren't in any of the original photos put out by NCE.


Even with the cooling vents in the top rear of the SB3 enclosure, I'm guessing that the SB3 may have experienced some overheating problems so NCE decided to add the holes afterward.  (Note the slight unevenness of the hole alignment in the picture.)


As you will also note from the picture, there is a fairly good size heat sink that is visible from both the top and side ventilation holes.


Setting things up
SB3 Connections


The SB3 comes with the following connections:


  • Rear (2) - A 4-port connector (black) for connecting the 2 wires of the 3-amp wall transformer (POWER) and the 2 wires to each track (TRACK), and a 3-port connector (green) for attaching additional DB3 3-amp boosters to the SB3

  • Front (3) - Cab bus "RJ" connectors for connecting the SB3 to the UTP (universal throttle port) panels


The rear 3- and 4-port connectors must be plugged into the internal circuit board connector of the SB3, which is accessible through a small slot in the back of the SB3 enclosure.  Each connector can be easily connected and disconnected from the internal circuit board connectors.  The front three RJ-12 connectors are mounted flush to the SB3 enclosure and require no additional setup.


3-amp transformer connection


The Digitrax PS315 3-amp wall transformer (purchased separately) came with a connector at one end.  Since the SB3 doesn't utilize that connector, I had to remove it and deinsulate each wire 5/16" in order to connect the transformer wires to the left 2 power ports of the SB3.  (The set screws in the top of each connector port make connecting and disconnecting the wires very easy.)


Fire them up together


When the SB3 is turned on, there are two indicator lights that light up.  The left indicator light (red LED) indicates that DC power is on.  The right indicator light (red/green/yellow LED) indicates that track power is on.


Getting nit-picky


My next comment is a personal preference, so please take it with a grain of salt.  Having done precision machining on a number of enclosures at my job, I was a bit disappointed with how the rear of the SB3 enclosure looked.


There is at least a ¼" gap on either side of the black 4-port connector, where the two LED indicator lights can be seen coming off the circuit board.  Granted, you won't really be looking at it all that much.  Still, I guess I expected more of a "finished" look to it.  In the long run, it really won't affect the operation of the SB3, and it probably provides an additional ventilation opening to help keep the SB3 cooler.


Wiring the SB3 to the layout


I did have to do some very minor rewiring in order to hook up the SB3 to the layout.  Because the SB3 can now be plugged into a UTP (universal throttle port), there is no longer a need for the PCP (Power Cab port) panel.* (See *CORRECTION below)


NOTE: To all non-NCE users - The Power Cab is required to be connected to the left (powered) front RJ-12 connector of the PCP panel (pictured below) in order to operate.  Since the Power Cab is the command station, booster, and throttle rolled up into one, if you disconnect the Power Cab from the panel, the whole layout shuts down.  The track wiring is also connected to the back of the PCP board, as pictured at the left.


*CORRECTION: I just discovered this evening that the PCP panel IS still needed in order to use the Power Cab in Program mode.  When the Power Cab is powered with the SB3, the USE PROGRAM TRK screen option mode is NOT available.  (It doesn't even display.)  Only when using the Power Cab alone with the PCP panel is the USE PROGRAM TRK screen option mode available or displayed.  I could not actually find this mentioned anywhere in the SB3 manual.  There was, however, a wiring diagram on pg. 3 (pictured below) that did "imply" it.


I think this bit of information was important enough that it warranted it being more clearly stated in the manual. My initial thought was to "decommission" (unpower) the PCP panel and just use it as a UTP panel.  After I discovered my misconception, I had to go back and repower the PCP panel, then move the SB3 wires to another Atlas slide switch.  (Not a big job; just a minor inconvenience.)


Utilizing the Smart Booster


So...What does it do for me?

With the SB3 now hooked up to the layout and powered to the UTP panel, seven things have happened to the Power Cab:


  1. It has increased its total maximum output from 1.7 amps to 3 amps

  2. Its OS has been upgraded from V.1.1 to V.1.28

  3. The number of accessible functions has increased from 13 (F0-F12) to 29 (F0-F28) – Obviously, this is entirely contingent on the total number of functions of a given decoder.

  4. Function refresh has been added – Points 3 & 4 are discussed in greater detail below under the heading, The winds of change below.

  5. It now has the capacity to run locomotives in both "Normal" AND "Yard" modes – Before the advent of the SB3, Yard mode was only accessible on the Pro Cab or the CAB-04p (potentiometer) throttles.  In Yard mode, the rotation direction of the thumbwheel or knob determines the direction of the locomotive.  (No direction button needs to be pushed.)  On the Pro Cab, pushing the thumbwheel upward causes the locomotive to go forward.  Pulling the thumbwheel downward causes the locomotive to go backward.  (Direction and speed steps are visible on the LCD screen of the Power Cab.)  Likewise, rotating the knob CW on the CAB-04p throttle causes the locomotive to go forward; CCW, backward.  This is a very handy and convenient feature to have - especially if you are using your locomotive for yard switching; requiring you to perform a lot of back and forth movements.

  6. It has become "more independent" - i.e. the Power Cab can now be connected to and disconnected from any "SB3-powered" UTP panel and function as a true "walk around" throttle – Even though my PCP panel is no longer used to power the Power Cab, I should still be able to use it as a UTP panel by purchasing another 4-conductor RJ-12 cable and connecting it to the back of the UTP panel (on the opposite side of the layout) that is powered by the SB3.  (NCE supplies an RJ-12 connector on the back of their PCP and UTP panel boards so that the panels can be easily "daisy-chained" to one another in order to accomplish this.)  Therefore, any UTP panel that is daisy-chained to the SB3-powered UTP panel becomes a useable connection port for the Power Cab. And, in conjunction with point 6...

  7. It has become "less significant" - i.e. the Power Cab is no longer a required item in order to operate your layout – That's right!  You read that last statement correctly!  You do NOT have to even use a Power Cab with the SB3 in order to operate trains.  You can use either a NCE Pro Cab or an NCE throttle (like an CAB-04p) to start, stop, change directions and operate CVs (i.e. configuration variables).  However, the Power Cab will still be required to perform any address or CV programming to your locomotives.


Start up


After plugging the Power Cab into a panel connector, I immediately noticed two things:


  1. The initialization or boot up time for the Power Cab to become functional is almost immediate - i.e. ~1 sec vs. 5-7 seconds when operating without the SB3.  The first time the Power Cab is plugged in after the SB3 has been turned on, the LCD briefly displays that the Power Cab is being powered by the SB3 by replacing the fast-clock time (in the upper right hand corner of the LCD) with the word "BOOSTER" (pictured at left).

  2. After 4-5 seconds, the fast clock is displayed once again.  If you unplug and reconnect the Power Cab to the UTP a 2nd time, "BOOSTER" will not display again and the fast clock will continue to elapse time.




  1. Short circuit protection - The SB3 comes with internal short circuit protection that will shut down track power in the event of a short. SB3 is design to "re-energize" the track every 2-3 seconds, until the short is cleared. I tested the feature by lay an X-acto knife handle across both track rails.  The SB3 manual states that this is "not intended to protect the booster from long term short circuits" and they strongly recommend an external short circuit protection device for that purpose.

  2. The SB3 Control bus connector (green) has two left terminals that are a low current copy of the track power output and a right hand terminal that is used for ground. The Cab bus connector is used for connecting additional NCE DB3 3-amp boosters to the SB3. This will come in handy for future expansion. And, the DB3 booster can also be used with other DCC systems, as well, and is a fairly inexpensive way of adding power blocks to your layout.


The winds of change


As mentioned earlier, there is a handy 6-page manual that comes with the Smart Booster.  (You can also download it from the NCE web site)  The manual states on pg. 4 (under the heading Changes from Power Cab V. 1.10) that there has been two significant changes made to the Power Cab, when used in conjunction with the SB3:


  1. Control of functions F13-F28 has been added

  2. Function refresh has been added to help keep the light and sound functions working on locomotives that don't remember the state of their functions on dirty track


Functions: Programming the OPTION key


In order to have access to these additional functions, the OPTION key or button has to be programmed to a value of "122".  To accomplish this, you must go into the Power Cab's internal setup program.  After a little bit of searching in the Power Cab manual, I was able to locate on p. 18 the steps on how to do this:


  1. Turn Smart booster on

  2. Unplug the Power Cab from the panel

  3. Reconnect the Power Cab to the panel, at the same time holding down the SELECT LOCO button. (At this point, you have now entered the Power Cab's internal setup program.)

  4. Press ENTER until you get "PROG OPTION KEY" on the LCD display

  5. Change the OPTION key value to "122”

  6. Press PROG/ESC to return to normal displayIt took me all of 30 seconds to complete the above programming. Very straightforward on the Power Cab.


It took me all of 30 seconds to complete the above programming. Very straightforward on the Power Cab.


Wiring the SB3 to the layout


I did have to do some very minor rewiring in order to hook up the SB3 to the layout.  Because the SB3 can now be plugged into a UTP (universal throttle port), there is no longer a need for the PCP (Power Cab port) panel.* (See *CORRECTION below)


Viewing new functions


Now that the OPTION key is programmed to the value of "122", the additional functions can be accessed:


  • Pressing the OPTION key once gives you the following LCD display

  • To access F13, all you have to do is press "3".  (In this mode 10 is automatically added to the number you press.)  To access F17, press "7", and so on.

  • Pressing the OPTION key a second time gives you access to F20-F28.  (In this mode, 20 is automatically added to the number you press.)

  • Pressing OPTION a third time toggles you back to F10-F19

  • Press PROG/ESC at any time to abort the operation


Viewing Function status


You can now also view the status of F0-F28 on one screen by simply pressing the EXPN key:


  • The top line gives you the status F1-F14; the bottom line, F15-F28.  The screen on the left states that F1, F2, and F3 are all ON.  A number means the function is ON; a dash means the function is OFF.

  • Press EXPN again to return the LCD screen to the normal display.


The one down side to this is that functions greater than 9 will be displayed with only one number*, so that you will need to know the orientation of a number to determine whether it is single or double digit.  For instance: F4, F14, and F24 would be displayed in the following matter:







The exceptions are F10 and F20, which are displayed as 10 and 20, as seen at the left.


Having all of them displayed makes it easier. But, how easy or quickly is it going to be to remember when only one or two of them are displayed? ("Oh, no…Wait! that F14...or F24?") I don't know. Maybe it won't turn out to be as confusing as I anticipate it might.


Function Refresh


As stated earlier, function refresh is for helping to keep the lights and sound functions working on locomotives that don't remember the state of their functions on dirty track.  According to pg. 4 of the SB3 manual, this is enabled through the SET_CMD_STA menu.  When function refresh is enabled, functions F0-F12 are refreshed "about once a second".


The SB3 manual also states that F13-F28 doesn't need to be refreshed "because decoders remember the function states for F13 and higher".  Like programming the OPTION key, enabling the function refresh feature took all of 30 seconds to accomplish.




Well, that about covers my NCE Smart Booster review.  Except for the addition of the walk around feature (very cool!), I'm not entirely sure how much the changes or the increase of power is going to be beneficial to me initially.  However, if and when my layout expands and/or I decide to wire my layout up "legitimately" and divide it up into power districts using the NCE CP6 module, I think my new Smart Booster will definitely begin to show its worth.


Initial overall rating and satisfaction: B+


UPDATE - 12/17/2008 - The above Smart Booster had to be sent back to the manufacturer in order to replace a faulty board. According to Larry Larsen @ NCE, the orginal boards (of which mine was one of them) were "problematic". Larry said the replacement would be FREE.


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