tams elektronik B-6 User manual

B-6
Booster for
digital model railway layouts
Item no. 40-19607
Manual
Front
Back
tams elektronik
n n n

Booster B-6 tams elektronik
Version: 1.0 | Status: 04/2023
© Tams Elektronik GmbH
ll rights reserved, in particular the right of reproduction, distribution and translation. Copies,
reproductions and alterations in any form require the written permission of Tams Elektronik
GmbH. We reserve the right to make technical changes.
Printin the manual
The formatting is optimised for double-sided printing. The standard page size is DIN 5. If
you prefer a larger display, printing on DIN 4 is recommended.
Notes on BiDiB®
The BiDiB devices described in this manual comply with the standards of the BiDiB
specification (status: V0.7). The BiDiB specification has been published on: www.bidib.org.
BiDiB® is a registered trademark. Copyrights and trademarks to BiDiB are held by Wolfgang
Kufer, OpenDCC.de.
In order to increase the readability of this text, we have refrained from referring to it
whenever the term BiDiB is used.
** The asterisks
The asterisks indicate further products from the Tams Elektronik GmbH product range :
Power-Splitter | Item numbers 40-20106, 40-20107
Digital control unit MasterControl 2 (mc²) | Item numbers 40-30007, 40-30017
Digital control unit RedBox | Item numbers 40-20007 … 40-20067
Digital control unit MasterControl | Item number 40-10007
2 | Contents

tams elektronik Booster B-6
Contents
1. Getting started.............................................................................................................5
1.1. Contents of the package.......................................................................................5
1.2. ccessories..........................................................................................................5
1.3. Intended use.......................................................................................................6
1.4. Safety instructions................................................................................................6
1.5. Care....................................................................................................................6
2. Your B-6......................................................................................................................7
2.1. Track voltage.......................................................................................................7
2.2. Displays and operation.........................................................................................8
2.3. Interfaces of the B-6............................................................................................9
Background information: Output signal................................................................10
2.4. Protocols............................................................................................................11
2.4.1. Digital formats..........................................................................................11
2.4.2. RailCom....................................................................................................11
2.5. Safety devices....................................................................................................12
2.5.1. Short-circuit switch-off..............................................................................12
2.5.2. Switching off in case of overtemperature....................................................13
2.5.3. Watchdog function....................................................................................13
2.6. Use with BiDiB....................................................................................................14
2.6.1. Features...................................................................................................14
2.6.2. Possible applications..................................................................................15
2.6.3. Wiring......................................................................................................16
2.6.4. ssignment in the BiDiBus system (addressing)..........................................16
3. Conception of the digital layout...................................................................................17
3.1. Dividing the layout..............................................................................................17
Background information: Short circuit of the booster outputs................................17
3.2. Supply with several boosters...............................................................................18
Background information: Track signals.................................................................18
Tip: Detecting equalising currents........................................................................20
4. Connections...............................................................................................................21
4.1. Connection to the power supply..........................................................................21
4.2. Connecting to the track.......................................................................................21
4.3. Connection to the digital central unit...................................................................23
4.3.1. Connection variant 1: BiDiB interface (RJ 45)..............................................23
4.3.2. Connection variant 2: DCC-compliant interface ("CDE")...............................24
4.4. Connection to a BiDiB-PC interface without track output function..........................25
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Booster B-6 tams elektronik
5. Settings / Configuration...............................................................................................26
5.1. Programming via BiDiB.......................................................................................26
5.2. Main track programming (POM)...........................................................................26
Recommendations for the settings.......................................................................29
6. Operation...................................................................................................................30
6.1. Operating and display elements...........................................................................30
6.1.1. Functions of the STOP-GO button..............................................................30
6.1.2. Display and RGB-LEDs...............................................................................31
6.2. ctivating the Watchdog.....................................................................................33
6.3. Switching the track voltage on and off.................................................................33
6.3.1. 6.3.1 Manual switching on and off of the track voltage................................33
6.3.2. utostart function.....................................................................................33
6.3.3. utomatic switching off of the track voltage...............................................34
6.4. Reset.................................................................................................................35
6.5. Driving operation................................................................................................35
6.6. Operation with BiDiB...........................................................................................35
7. Update.......................................................................................................................36
8. Checklist for troubleshooting and error correction.........................................................37
8.1. utomatic shutdown...........................................................................................37
8.2. No short circuit switch-off...................................................................................37
8.3. Problems with control via the BiDi bus.................................................................37
8.4. Problems with the Watchdog Function.................................................................38
8.5. Technical Hotline................................................................................................38
8.6. Repairs..............................................................................................................38
9. Technical data............................................................................................................39
9.1. Booster B-6........................................................................................................39
9.2. Power supply unit...............................................................................................41
10. Warranty, EU conformity & WEEE................................................................................43
10.1. Guarantee bond.................................................................................................43
10.2. EU Declaration of Conformity..............................................................................44
10.3. Declarations on the WEEE Directive.....................................................................44
4 | Contents

tams elektronik Booster B-6
1. Getting started
This manual will help you step by step to install and use your booster B-6 safely and properly.
Before you start using the booster, read through this manual completely, particularly the
chapter on safety instructions and the checklist for trouble shooting. You will then know where
to take care and how to prevent mistakes which take a lot of effort to correct.
Keep this manual safely so that you can solve problems in the future. If you pass the booster
on to another person, please pass on the manual with it.
1.1. Contents of the package
booster B-6
power supply unit
mains cable (black) with Euro plug (CEE 7/16) and plug for mains cable socket (European
version / C7)
connection cable (green) with RJ-45 connectors (at least Cat. 5e)
1 plug-in connection terminals 2-pole, RM 3.81
1 plug-in connection terminals 3-pole, RM 3.81
4 plastic brackets for fixing the booster
1.2. ccessories
Connection cables
Digital control unit via DCC-compliant
booster interface ("CDE")
Stranded wire*, recommended cross-section
> 0,25 mm²
Digital control unit
via BiDiB-interface
Patch cable (RJ 45)
Note: patch cable is included in the scope of delivery.
Track
Stranded wire*, recommended cross-section:
0,75 mm² bis 1,5 mm²
(depending on current)
* The use of stranded wire is recommended for making the connections. Stranded wires
consist of several thin individual wires and are therefore more flexible than rigid wires with the
same copper cross-section.
Distribution of the booster current
In order to utilise the current of 6 that the B-6 can provide, even with smaller nominal sizes,
a power splitter** can be used. The power splitter distributes the current to 2 to 3 booster
sections with 2 to 3 each.
Getting started | 5

Booster B-6 tams elektronik
1.3. Intended use
The booster B-6 is intended for use in digital model railway layouts as specified in the
instructions. ny other use is not in accordance with the intended use and will result in the
loss of the warranty claim. Intended use also includes reading, understanding and following all
parts of the instructions. The booster is not intended to be used by children under the age of
14.
1.4. Safety instructions
Improper use and non-observance of the instructions can lead to incalculable hazards. Prevent
these dangers by carrying out the following measures:
Use the booster and the power supply unit only in closed, clean and dry rooms. void
humidity and splash water in the environment. fter condensation has formed, wait two
hours for acclimatisation before use.
Disconnect the booster from the power supply before carrying out wiring work.
Only plug the mains plug of the power supply unit into properly installed and fused earthed
sockets.
Heating of the booster and the power supply unit during operation is normal and harmless.
Keep a distance of at least 20 cm between the sides, the top and the back to surrounding
surfaces to allow unhindered air exchange and to predect the units from overheating.
Do not expose the units to high ambient temperatures or direct sunlight. Observe the
information on the maximum operating temperature in the technical data.
Regularly check the operational safety of the units, e.g. for damage to the connection
cables or damage to the housing.
If you notice damage or if malfunctions occur, switch off the supply voltage immediately.
Send in the booster and/or the power supply unit for inspection.
Dangerous voltages occur inside the power supply unit. Therefore, never open the housing
of the power supply unit.
1.5. Care
Do not use any cleaning agents to clean the booster and the power supply unit. Only wipe the
units dry. Disconnect the units from the power supply before cleaning.
6 | Getting started

tams elektronik Booster B-6
2. Your B-6
Boosters have three main tasks:
1. supply the current needed to operate the digitally controlled locomotives and turnouts, but
also other (digital) consumers.
2. to bring the voltage to the track so that the digital driving and switching commands arrive
at all vehicle and accessory decoders.
3. in case of a short circuit on the layout (e.g. derailment of a vehicle), ensure that the
current is switched off and damage to the rails and the vehicles is prevented.
In RailCom-monitored layouts, the booster also provides the so-called RailCom cutout, which is
required for the transmission of the feedback data.
2.1. Track voltage
The Booster B-6 can provide 2 to 6 of current at the track output, depending on the setting.
The maximum output current set for the booster is identical to the cut-off current, when
reached, the layout is switched off for safety reasons (e.g. in case of a short circuit). The
switch-off current must be lower the smaller the nominal size (and the more filigree rails or
vehicle parts such as wheel sliders are).
→ Section 5 "Recommendations for the settings".
Division of the booster current
In order to be able to utilise the current of 6 that the B-6 can provide, even with smaller
nominal sizes, a power splitter** can be used. The power splitter distributes the current to 2
to 3 booster sections with 2 to 3 each.
Connectin additional boosters
If the current requirement is higher than the current provided by the B-6, a corresponding
number of further boosters must be connected to supply the digital model railway layout.
→ Section 3 "Conception of the digital layout"
Back round information:
Rou h calculation of the current requirement
1 locomotive nominal size N: 600 m
1 locomotive nominal size H0: 800 m
1 locomotive nominal size 0: 1,000 m
Carriage interior lighting: 50 - 200 m
one other consumer
(e.g. sound module): 100 - 300 m
Reserve for turnouts 10 % of the determined total
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Booster B-6 tams elektronik
2.2. Displays and operation
Display (7-se ment display)
The 2-digit 7-segment display shows you essential information, e.g.
the current power consumption in the booster circuit
the operating status (e.g. normal operation, stop, short circuit, overheating)
during programming: the set values
RGB LEDs in the housin
The top of the B-6 is made of translucent plastic. During operation, RGB LEDs built into the
housing clearly indicate the operating status of the B-6, e.g.
"normal operation" (green) or "stop, track power is switched off" (red)
change to programming mode, send BiDiB Identify signal
short circuit, overtemperature
STOP-GO button
The button can be used to manually switch the track voltage on or off at the output of the B-6
independently of the connected digital control unit. The button is also used to
trigger a restart
identify the B-6 via BiDiB with the PC control software (BiDiB-Identify)
Switchin on and off with a DCC turnout command
The track voltage at the output of the B-6 can alternatively be switched on and off via DCC
turnout setting commands sent to a turnout address assigned to it.
Autostart function
ctivating or deactivating the autostart function determines whether the track voltage at the
booster output is automatically switched on as soon as the track signal is present (the control
unit is set to "GO") or not.
Even if the autostart function is activated, the track voltage at the booster output is not
switched on automatically if it was previously switched off with the STOP-GO button or the
booster was switched off due to overheating or by triggering the watchdog.
If the autostart function is inactive, the track voltage must always be switched on (again) by
pressing the STOP-GO button.
8 | Your B-6

tams elektronik Booster B-6
Confi uration
The Booster B-6 can be adapted to individual requirements:
via BiDiB with PC software that supports BiDiB, or
via main track programming (POM) according to RailCommunity standard RCN-226 ("DCC
protocol | special values for configuration"), which regulates, among other things, the
configuration of devices that do not have their own address and whose connection to a
programming track is not possible or reasonable. For further information see RailCommunity
standard RCN-226 (at: www.railcommunity.org).
2.3. Interfaces of the B-6
Power supply
Only the supplied power supply unit may be used as the power supply for your B-6 and the
components of your layout that are supplied by the B-6. Conventional model railway
transformers are not suitable as power supply for the B-6.
Track connection
The B-6 provides a regulated, symmetrical track voltage, which is adjusted in 1 V steps to a
value between 8 and 22 V. It can thus be optimally used for operation with model railways. It
can thus be optimally adapted for operation with layouts of different nominal sizes. On
delivery, the track voltage is set to 18 V.
The regulation of the track voltage to a fixed value prevents the driving speeds of the
locomotives and the brightness of the illuminations from varying as a result of voltage
fluctuations.
→ Background information "Output signal" (next page)
Booster interfaces
The B-6 has two different booster interfaces, which are optionally used for connecting the
digital control unit and other boosters:
DCC-compliant booster interface (3-pole / "CDE"): for connection to the DCC-compliant
booster interface of a control unit or the track output of a control unit.
BiDiB interface (RJ 45): for connection to the BiDiB interface of a BiDiB device with track
output function, a BiDiB interface or further BiDiB nodes (e.g. further boosters, stationary
decoders, feedback devices).
→ Section 2.6 "Use with BiDiB"
Your B-6 | 9

Booster B-6 tams elektronik
Background information: Output signal
Symmetrical output si nal
The output signal is created by constantly reversing the polarity of the transformer voltage
according to the specifications of the digital control signal from the central unit. Since the
same voltage is always present at the output (alternately positive and negative), the output
voltage at the booster output of the B-6 is 100 % symmetrical.
Use of the ABC brakin method
This symmetrical output voltage is required for the use of the BC braking method. The BC
braking method is based on the fact that, deviating from standard operation, asymmetrical
voltages are generated at the two conductors in the braking sections.
Galvanic separation  Continuous system round
In digital layouts, the circuits supplying the tracks and the digital equipment can either be
galvanically (i.e. electrically) separated from each other or connected to a common,
continuous ground. Establishing a common, continuous ground is prone to errors in practice
and therefore unreliable, especially in larger installations.
By using galvanically separated circuits, ground loops ("hum loops") and fault currents, which
can cause malfunctions and in the worst case damage to the digital devices, can be reliably
prevented.
The inputs and outputs of the B-6 are galvanically separated from each other by optocouplers.
This means that there is no electrical connection between the digital control unit and the
booster output.
Use with s88 feedback units
If a common system ground is required, e.g. when using the s88 feedback system, the ground
connection of the s88 feedbacks must be connected to a rail. Just as with the use of ground-
related boosters, it is also crucial with this variant that the ground connection is made to the
"correct" rail, i.e. always to the continuous rail.
10 | Your B-6

tams elektronik Booster B-6
2.4. Protocols
2.4.1. Digital formats
The Booster B-6 is multi-protocol capable, it can transmit data (via both the DCC compliant
and BiDiB interfaces) in the following formats:
DCC
Motorola I and II
m³ and mfx: The B-6 transmits control commands in m³ and mfx format, but no mfx
feedback.
DCC-A
The RailCom-based extension of the DCC format according to RailCommunity Norm RCN-218
enables the automatic registration of vehicle decoders with the central unit.
→ RailCommunity standard RCN 218 (at: www.railcommunity.de)
Currently (as of pril 2023), the B-6 is not able to forward the automatic registrations of
vehicle decoders to the central unit, as the required standard defining the data transmission is
still in progress. In a later software version the Booster B-6 will support registrations via DCC-
. The update will be available for download free of charge.
2.4.2. RailCom
RailCom cutout
The Booster B-6 can provide the so-called RailCom-Cutout, which enables the transmission of
feedback data in RailCom-monitored sections.
When using the B-6 with central units that send a DCC signal and are not RailCom-capable,
the RailCom-Cutout can lead to disturbances in the data transmission. Some older DCC vehicle
decoders and some current DCC decoder types (especially from US manufacturers), which are
not designed for use with RailCom, do not react correctly to run commands when RailCom
cutout is switched on. With non-RailCom-capable DCC sound decoders, the sound reproduction
can be disturbed.
Therefore, the B-6 offers the possibility to switch RailCom on or off (RailCom is switched on in
the delivery state).
In the case of pure Motorola central units, interference with data transmission through the
RailCom cutout is excluded due to the principle.
Inte rated lobal RailCom detector
global RailCom detector is integrated in the Booster B-6, which receives feedback from
decoders in channel 2. ccording to the RailCom standard, channel 2 is reserved for feedback
from decoders to whose address a DCC command was previously sent.
The RailCom feedback messages are forwarded by the B-6 via the BiDi data bus to RailCom
display devices or the PC.
→ Section 2.6 "Use with BiDiB"
Your B-6 | 11

Booster B-6 tams elektronik
2.5. Safety devices
2.5.1. Short-circuit switch-off
The B-6 has an internal short-circuit cut-off which automatically sets the booster to "STOP"
(i.e. switches off the track voltage at the output) in the event of a short-circuit at the track
output. This prevents defects on the booster, the track and the vehicles. The time until the
short-circuit switch-off responds (= short-circuit sensitivity) can be set to a value between 20
and 200 milliseconds.
The cut-off current in case of a short circuit (= maximum track current) can be set to a value
between 2 and 6 (in 1 steps). In order to effectively prevent damage in the event of a
short circuit, the cut-off current must not be set too high, especially for smaller nominal sizes.
→ Section 5 "Recommendations for the settings".
Short-circuit feedback
How the digital control reacts when the maximum current at the track output of the booster is
exceeded (e.g. a short circuit) depends on the connection of the booster:
Connection of the short-circuit feedback line ("CDE") to a digital central unit via the DCC-
compliant booster interface: The booster reports the exceeding of the maximum current to
the control unit, which switches the complete layout to "STOP". This solution is useful for
automated driving, for example.
Connection to the track output of a central unit or omitting the connection of the short-
circuit feedback line: If the maximum current is exceeded, the booster automatically
switches off the track voltage for the connected booster circuit. Operation continues in
further booster circuits. This solution is suitable for areas with independent operation, e.g.
in the depot.
Connection to a BiDiB PC interface (separate or integrated in the digital control unit): Based
on the status messages and operating values sent by the B-6 via the BiDi bus, the PC
control takes over the complete booster management.
Connection to a digital central unit via the BiDiB interface without integration in a BiDiB
control: The digital central unit can react on receipt of a short-circuit message via the BiDi
bus, provided it supports this function and is configured accordingly. → Manual of the
digital central unit.
Automatic restart after a short circuit
If the digital control unit cannot receive a short-circuit feedback or is configured to ignore this
message, the Booster B-6 automatically switches the track signal at the output back on ("GO")
after 4 to 10 seconds have elapsed following a short-circuit. If the short circuit is still present,
it switches the track signal off again immediately.
In the delivery state, the automatic switch-on is interrupted for one minute after the booster
has switched itself on and off again five times. This restart time after 5 short circuits can be
individually adjusted to a value between 0 and 90 seconds.
12 | Your B-6

tams elektronik Booster B-6
Inrush time
The sum of the charging currents of buffer capacitors on vehicle decoders (especially sound
decoders) and additional external backup capacitors can become so high when the layout is
switched on that the short-circuit disconnection of the booster reacts immediately. This makes
it difficult to start up the layout when the short-circuit cut-off is active.
The B-6 can accept an increased current of 6 for a short time (adjustable up to max. 500
ms) after switching on, regardless of the set cut-off current, and tolerates the brief collapse of
the voltage. This time is sufficient to charge buffer capacitors and backup electrolytic
capacitors. Only if the current does not drop again after the set time and the voltage does not
rise again, the short-circuit switch-off of the B-6 reacts (because then a "real" short-circuit can
be assumed).
Further information on inrush current: RailCommunity standard RCN 530 (at:
www.railcommunity.de).
2.5.2. Switching off in case of overtemperature
In case of overheating, the booster automatically switches off the track voltage for safety
reasons. Possible causes:
obstruction of air exchange
very high ambient temperature or direct solar radiation with simultaneous high load.
2.5.3. Watchdog function
The watchdog is used in PC-controlled layouts to check whether the digital signals are
transmitted in a booster circuit. For this purpose, the central unit (controlled by the PC
software) sends a DCC turnout setting command to a turnout address assigned to the B-6 at
intervals of max. 5 seconds. s soon as the B-6 no longer receives these commands, it
automatically switches off the track voltage.
fter switching on the B-6, the watchdog function is initially inactive. It is activated by sending
an adjustment command to the assigned turnout address. This makes it possible to control the
layout without PC control without deactivating the watchdog function.
Your B-6 | 13

Booster B-6 tams elektronik
2.6. Use with BiDiB
The Booster B-6 is in the sense of the BiDiB specification a device of the class "Booster" with
the additional specification "BiDi-(RailCom-)Detector".
2.6.1. Features
ccording to the BiDiB specification, data can be sent to and from the B-6 via the BiDi bus.
Settin options
On the PC, all settings for the B-6 can be made, e.g.:
output voltage
RailCom cutout on/off
maximum output current
reconnection time after a short circuit
In addition, an update can be carried out via the software.
Status messa es and reportin of operatin values
During operation, the B-6 sends its current operating status, including information about the
cause of the current status, as well as its current operating values to the PC via BiDiB, e.g.
track voltage at the booster output is switched on ("GO")
track voltage at the booster output is switched off, e.g. due to short circuit,
overtemperature, missing mains voltage ("STOP")
actual current consumption
actual voltage at track output
current operating temperature
These messages can be evaluated by the PC control software and serve as a basis for booster
management.
Inte rated RailCom detector
The integrated global RailCom detector sends the RailCom messages from the connected
booster circuit to the PC via BiDiB:
vehicle addresses
CV responses of the vehicle decoders
dynamic information, i.e. CV contents that change during operation: e.g. real speed,
reception statistics, tank contents
14 | Your B-6

tams elektronik Booster B-6
2.6.2. Possible applications
The Booster B-6 can be operated together with up to 31 other nodes on one level. It can be
used together with different types of so-called track output devices in the BiDi bus:
Digital central units with integrated BiDiB-PC interface (e.g. MasterControl 2**).
Digital central units without BiDiB interface (e.g. MasterControl**, RedBox**) in
combination with BiDiB PC interfaces (e.g. ZEUS**)
In both variants, all settings for the B-6 can be made on the PC with the help of software that
supports BiDiB. The B-6 sends its status messages and operating values as well as the
RailCom messages to the PC via the BiDi bus. These messages serve as the basis for the
booster management of the control software, which, for example, ensures that the booster is
switched off in the event of a short circuit or overtemperature.
With di ital central units with inte rated BiDiB PC interface
The DCC track signals are sent to the B-6 via the BiDi bus. Vehicle decoders and conventional
accessory decoders that are not designed for BiDiB receive their digital commands via the rails
in the connected booster circuit.
With di ital central units without BiDiB interface
The DCC track signals are sent to the B-6 via the DCC-compliant ("CDE") booster interface.
Status messages and operating values of the B-6 as well as the RailCom messages are sent
from the B-6 to the PC via the BiDiB PC interface and are available there as a basis for the
booster management of the control software.
Your B-6 | 15

Booster B-6 tams elektronik
2.6.3. Wiring
In accordance with the BiDiBus specification, patch cables with RJ 45 connectors (Cat5 cables)
are provided as bus cables for the B-6 booster. These cables are easy and quick to handle and
ensure secure connections to the interface and to other nodes. Connecting and disconnecting
the cables during operation is permitted (hot plug).
2.6.4. ssignment in the BiDiBus system (addressing)
ccording to the BiDiB specification, the assignment of the booster B-6 in a BiDi bus system is
automatic. s a basis for the automatic assignment, a unique number, the Unique-ID, is
programmed into the B-6 by the manufacturer. When the BiDiB system is switched on, the
interface searches for the existing nodes within its structure, creating a list of available nodes,
their Unique ID and a local address valid for this session.
If a new node is connected to the bus, the list of available nodes is automatically expanded
and the interface sends a corresponding message to the PC.
The Booster B-6 has a so-called "Identify button" according to the BiDiB specification. fter
pressing the button, the booster is highlighted in the screen display of the nodes and the RGB
LEDs under the top cover flash.
16 | Your B-6

tams elektronik Booster B-6
3. Conception of the digital layout
3.1. Dividing the layout
Divide your layout into individual, electrically separate sections (booster circuits), each
supplied with its own booster. maximum of three to five locomotives should run in each
booster circuit at the same time. The following subdivisions are useful:
station
depot
main line (if necessary in several sections)
secondary line (if necessary in several sections)
rrange the transitions between the booster circuits in such a way that
they are crossed as little as possible
in operation, never more than one crossing point between two booster circuits can be
bridged by a (long) train (i.e. not two crossing points between three booster circuits).
Background information: Short circuit of the booster outputs
s soon as a vehicle bridges the separation point between two booster circuits, the track
outputs of the two associated boosters are connected to each other. If this connection is only
for a short time, the risk of this damaging the boosters is low. The situation is different if the
vehicle stops at the separation point. If in this case the short-circuit disconnection does not
react or reacts too late, the track outputs of the boosters can be damaged.
The risk of damage to the boosters increases significantly if a train is so long (or the
separation points between several booster circuits are arranged so close together) that it
connects more than two booster circuits and thus more than two boosters with each other
when passing over them.
Conception of the digital layout | 17

Booster B-6 tams elektronik
Cut the transitions between the booster circuits as follows:
For 2-conductor layouts: one rail. Make sure that you cut the same rail ("left" or "right") in
all booster circuits. In larger, unclear systems, it is recommended to cut both rails.
In centre-conductor layouts: the centre conductor.
3.2. Supply with several boosters
If possible, a layout should be supplied by identical boosters from the same manufacturer. If
necessary, ask the manufacturer whether and, if so, which booster models can be combined
with each other. Different booster models can be used on one layout if they are used for
completely separate parts of the layout (e.g. standard gauge line and narrow gauge line) or
separately for the tasks "switching" and "driving".
If boosters are connected to a central unit or a small digital control unit via the track output,
the integrated and external boosters should generally not be used together to supply the
layout with traction current. The booster integrated in the central unit can be used sensibly for
switching the accessory decoders in its own booster circuit.
Background information: Track signals
The digital track signals that the boosters receive
from the central unit need a certain amount of time
to be processed and to get from the data input to the
track output. This processing time is different for
each booster due to its design. Even for boosters of
the same design it differs due to component and
manufacturing tolerances. slight time shift of the
voltage characteristics is therefore the normal state.
The more different the run-through time of the
signals in the two boosters, the greater the time shift
of the voltage curves. This can go so far that a
positive voltage is already present at the output of
one booster and a negative voltage is still present at
the next booster, which is controlled by the same
central unit.
If the two booster circuits are connected to the
booster outputs with different polarity, opposite
voltages will be present. If the isolating points
between the booster circuits are bridged, the track
voltage is twice the set maximum track voltage.
18 | Conception of the digital layout

tams elektronik Booster B-6
Equalisin currents and double track volta e
When crossing the separation points, equalising currents occur between the (briefly differently
polarised) booster circuits, even when using identical boosters from the same manufacturer.
These currents are harmless for rails and vehicles and do not affect the operation.
The more different the voltage curve is in the two booster circuits, the higher the equalising
currents are. High equalising currents can cause short circuits on boosters, rails, wheels and
sliders.
In addition, the applied track voltage always doubles when opposite voltages are applied in
the two booster circuits. The longer opposite voltages are present, the more serious the
consequences.
The possible consequences of short circuits and doubled track voltages:
damage to wheels, sliders and rails
damage to the track outputs of the boosters involved
"Data salad"
Due to a shift in the voltage curves in the two booster circuits, the vehicle decoders receive
information that differs from each other and may interpret it incorrectly. This can lead to the
following phenomena, for example:
Locomotive decoders understand the signal as an impulse to switch to analogue mode.
However, since the locomotives are on the digital track, they race off at top speed.
Locomotive decoders read out a run command for their address from the faulty data signal
and set locomotives in motion as if by magic.
Functions such as lighting or sound are switched on or off without the corresponding
switching commands having been entered at the central unit.
The differences in the throughput time of the data are particularly large when the layout is
jointly supplied with traction current by the booster integrated in the central unit and external
boosters connected via the track output.
Conception of the digital layout | 19

Booster B-6 tams elektronik
Tip: Detecting equalising currents
The question of whether or not dangerous equalising currents occur at a booster separation
point can be detected relatively easily with the help of a model railway incandescent lamp
connected to the rails or the centre conductors across the separation point.
Note: For the test, use an incandescent lamp whose maximum voltage corresponds
approximately to the set maximum track voltage. Suitable are e.g. bulbs with integrated
cables or wire ends. LEDs are not suitable for this test!
Ideally, the lamp does not light up or only lights up very
weakly. This case occurs when a power splitter** is used
that distributes the output current of a booster to 2 or 3
booster sections or when using identical boosters from
one manufacturer whose component and manufacturing
tolerances are very small.
With well-matched, properly connected boosters, the lamp
glows a little. When passing over the separation points, no
damage to vehicles, tracks or boosters and no problems
due to faulty data transmission are to be expected.
If the lamp glows visibly, it is not recommended to start
operation. The two boosters should be checked in any
case:
Is the same output voltage set for both boosters?
Is the RailCom gap switched on for the boosters? If
yes, the test should be repeated with the RailCom
switched off. If the lamp then only glows, operation
with RailCom switched on can be started without
hesitation.
Boosters of different types / from different
manufacturers may not fit together. It is advisable to
check with the manufacturer.
One of the two boosters is defective. check by the
manufacturer is recommended.
If the lamp lights up brightly, the start of operation can
have fatal consequences for vehicles, tracks and the
connected boosters! Either the two boosters are
connected to the rail / centre conductor with different
polarity or the two boosters do not fit together and should
therefore not be used together.
20 | Conception of the digital layout