Lenz Digital Plus SILVER Series User manual

B.10.082
SILVER Decoder
Operating Manual
Art. no. 90006
1st edition, 09 05

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Contents
1 Important advice, please read first! ...................................................................... 4
2 Features of the SILVER decoder.......................................................................... 5
2.1 Motor control ........................................................................................................ 5
2.2 Capacity ............................................................................................................... 5
2.3 Overload protection .............................................................................................. 5
2.4 Starting and braking delay.................................................................................... 5
2.5 Constant braking distance.................................................................................... 5
2.6 Shunting speed .................................................................................................... 6
2.7 ABC = simple signal stop and slow approach.......................................................6
2.8 Push-pull train control........................................................................................... 6
2.9 Function outputs................................................................................................... 6
2.10 Lighting effects ..................................................................................................... 6
3 Setting (programming) the decoder......................................................................7
3.1 Variable decoder features - Configuration Variables (CV) .................................... 7
3.2 Standardisation in NMRA .....................................................................................8
3.3 Different presentations of numerical values: "bits" in CVs .................................... 9
4 Installation.......................................................................................................... 11
4.1 Preparations and tests before installation........................................................... 11
4.2 Affixing the decoder............................................................................................11
4.3 Locomotives with interface ................................................................................. 11
4.4 Locomotives without interface ............................................................................ 12
5 Setting the address ............................................................................................ 15
6 Setting the motor control ....................................................................................16
6.1 Selecting the motor type..................................................................................... 16
6.2 Switching the control on and off ......................................................................... 17
6.3 Switching off the high-frequency control............................................................. 17
6.4 Activating the EMF switch .................................................................................. 17
6.5 Repeat rate ........................................................................................................ 17
7 General settings ................................................................................................. 18
7.1 System change during analogue operation ........................................................ 19
7.2 System change with switched-off analogue operation ........................................ 20
8 Overload protection............................................................................................ 21
9 Starting and braking delay.................................................................................. 22
9.1 Switching off the starting and the braking delay.................................................. 22
10 Minimum, maximum and mid speed................................................................... 24
11 Characteristic speed line .................................................................................... 26
12 Constant braking distance.................................................................................. 27
12.1 Setting the constant braking distance:................................................................ 27
13 Shunting speed .................................................................................................. 29

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13.1 Mapping the shunting speed to a function .......................................................... 29
14 Setting the function outputs................................................................................ 30
14.1 Function mapping of function outputs................................................................. 30
15 Effects at function outputs.................................................................................. 34
15.1 Setting the brightness (dimming)........................................................................ 34
15.2 Effects at outputs A and B.................................................................................. 35
15.3 Effects at outputs C and D ................................................................................. 36
16 ABC – simple signal stop ................................................................................... 39
16.1 Activating ABC ................................................................................................... 40
16.2 Setting the slow speed ....................................................................................... 40
16.3 Important advice on ABC ................................................................................... 40
17 Push-pull (shuttle) train control........................................................................... 41
17.1 Push-pull operation without intermediate stop .................................................... 41
17.2 Push-pull operation with intermediate stop ......................................................... 42
17.3 Important advice on the push-pull control:.......................................................... 44
18 Resetting the decoder ........................................................................................ 44
19 Appendix............................................................................................................ 45
19.1 Programming and reading out of decoder features............................................. 45
19.2 Advice on programming the extended locomotive address with other systems .. 46
19.3 Dividing the extended locomotive address into CV17 & CV18............................ 46
19.4 Bits and bytes – conversion help........................................................................ 49
19.5 Brake generator ................................................................................................. 49

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1 Important advice, please read first!
All features described here as well as advice given on
programming and operation only apply to the SILVER decoder
series. Other Digital plus by Lenz ®decoders may have identical
or similar features, but they may be operated or programmed
differently. Please use this manual only for decoders of the
SILVER series.
Digital plus locomotive decoders are to be used only with
Digital plus by Lenz ®or other standard digital control systems
with an NMRA-conformance seal and on NEM-conform DC
systems. If in doubt, ask the system supplier.
The current-carrying capacities noted in the technical data may
not be exceeded as this could damage the decoder! Under no
circumstances may the parts of the locomotive decoder be
allowed to touch the metal components of the chassis or the
body of the locomotive as this could cause a short-circuit within
the locomotive decoder leading to damage.
Never wrap the locomotive decoder in insulating tape as this
prevents the necessary air circulation around the decoder.
Instead, use insulating tape or something similar around the
metal components of the locomotive to avoid unintentional short-
circuits without depriving the decoder of air. Use double-sided
adhesive-tape to affix the decoder.
On two-wire layouts, locomotives equipped with Digital plus
decoders must not be run using live overhead lines as this could
subject the locomotive to double the voltage, if placed on the
track in the wrong direction, and damage the decoder!
Before installing a Digital plus decoder, check the locomotive in
normal DC operation to ensure that it works correctly before
modifying it. Replace worn wheel contacts, motor brushes and
blown bulbs. Only a locomotive that is mechanically OK will
function properly with a locomotive decoder.

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2 Features of the SILVER decoder
The following is a brief overview of the common features of the
SILVER decoder series. For more detailed information as well as
advice on how to use and alter these features, please read the
following sections.
2.1 Motor control
The decoder has a high-frequency control (23kHz). To adapt it to
the type of locomotive used, you can simply choose between
different motor types. These individual motor types include
parameter sets which have been specially adapted to the
respective models. Moreover, it is also possible to carry out fine-
tuning via various CVs.
Of course you can switch off both the high-frequency control as
well as the control system itself.
The minimum, maximum and mid speed can be set; the decoder
adapts the characteristic speed line dynamically to ensure a
steady, smooth curve. Independently of this, it is also possible to
program an individual characteristic speed line.
You can use up to 128 running notches.
2.2 Capacity
We have defined the continuous or maximum current-carrying
capacities of the SILVER decoder motor outputs. The
continuous load is achieved without special installation on
cooling surfaces!
2.3 Overload protection
The decoders are protected against short circuits.
2.4 Starting and braking delay
The starting and braking delays can be set independently of
each other. These delays can be enabled and disabled via a
function by pressing the key of the digital system once.
2.5 Constant braking distance
A special feature of the SILVER decoder provides for a constant
braking distance independent of the current speed of the
locomotive. This feature is important for model railway operators
who install automatic stopping sections in their layouts.

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2.6 Shunting speed
The shunting speed can be set via a function; it halves the
speed.
2.7 ABC = simple signal stop and slow approach
You can carry out a particularly simple signal stop using the ABC
braking module. Combined with the constant braking distance,
precise on-the-spot stopping in front of red signals is not a
problem.
The signal indication "Slow approach/Caution" does not pose a
problem; the respective speed can be set via a CV in the
decoder.
You can operate all functions during the signal stop or slow
approach - you can even reverse away again from the red signal.
These special ABC modules BM3 can be used to assemble a
block section of any desired length.
2.8 Push-pull train control
A push-pull train control can be set if the ABC braking module
BM2 is used. There are two different options: push-pull operation
with and without intermediate stops. The latter also takes slow-
approach sections into account. The stopping time at the end of
the track and at the intermediate stops is set at between 1 and
255 seconds via a CV.
2.9 Function outputs
The function outputs can be mapped to the functions of the
digital system according to NMRA.
2.10 Lighting effects
Different lighting effects can be set at the four function outputs:
•Setting the brightness (dimming), can be switched via a
function as desired
•Mars light
•Gyra light
•Strobe and double strobe
•Different settings for random flickering (ideal for a steam
locomotive’s fire box)
•Flashing

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3 Setting (programming) the decoder
This section describes the basic setting of features. If you are
already familiar with so-called "CVs" and their operation you may
skip this section.
Unless stated otherwise in the detailed operating manuals, all
settable features can be programmed both via "Programming in
operational mode (PoM)" and "Programming on the
programming track".
3.1 Variable decoder features - Configuration Variables (CV)
The number of the decoder’s functional outputs cannot be
altered since it is determined by its hardware. The maximum
current load is also a feature that cannot be altered.
However there is a wide range of features which are not
determined by the decoder’s hardware but by its software. These
features can be altered to a great extent. The most important of
these features for normal operation are the locomotive address
and the starting and braking delay.
There is a storage location for each feature within the decoder. A
figure is stored in each storage location.
These storage locations are similar to cards in a index card box.
Each decoder has a "card index box". Each "card" holds a
feature of the locomotive decoder, for example on "card" number
1 the locomotive address, on "card" number 3 the starting delay.
This means one card for each feature. Depending on the
number of features available in the decoder, the size of the
"index card box" varies.
This "index box" functions as a "command station" in the
decoder. The information stored here largely defines the
decoder’s behaviour. For example, one of the "cards"
determines whether the locomotive decoder also reacts to
conventional DC.
If you imagine that these cards are written in pencil, it is possible
for you to alter the entry by simply "erasing" and "rewriting" it.
This is done while programming the locomotive decoder on the
programming track. The comparison with the eraser is not
completely correct, because there are no empty "cards". There is
always something written on them, even if it is only 0. However
this does not necessarily mean that the content is not interesting.
And -the exception proves the rule- there are also cards whose

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content you can read but not delete, for example the version
number and the manufacturer code.
On each "card" you will find a numerical value; the general range
of values of each card is 0 to 255. Whether all possible
numerical values of this range are sensible depends on the
individual feature. And there are also "cards" on which the
numerical value is presented in a different way in order to
facilitate handling. This will be explained in more detail at a later
stage.
Since you can alter the numerical values on the index cards (in
these storage locations) at any time, they are often called
variables. These variables are used to determine features; you
use them to configure, and that is how the term "Configuration
Variable", abbreviated to CV, developed (in the US).
From now on we will not refer to index cards, but instead we
shall use the correct term CV. CVs are used to determine the
decoder’s features or behaviour.
3.2 Standardisation in NMRA
The NMRA (National Model Railroad Association; American
association of model railway operators, the largest association of
its kind worldwide) specified in one of its standards which CV
determines which feature. This is an advantage for you since the
same feature is always assigned to the same CV if the decoder
you use was developed in accordance with the standard. Simply
keep in mind which CVs are important for your operation and you
will never be confused, even when working with several
decoders.
There are certain CVs a decoder must have to fulfil the NMRA
standardisation criteria. These CVs are a requirement of the
"Conformance Seal". For the manufacturer of a decoder, this
seal functions as a certificate confirming that the decoder was
inspected by an independent NMRA body for compliance of its
features with the standard.
The manufacturer may use other CVs in a decoder, although this
is not imperative. However, if CVs are used, they must be
designed in accordance with the standard.
Finally, there is another range of CVs which the manufacturer
can specify freely.

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3.3 Different presentations of numerical values: "bits" in CVs
CV1 contains the basic address of the locomotive decoder. It is
easiest if you are able to enter this address as a numerical
value. However, it is also possible that several features are
influenced in a CV. An example of this would be the switching on
and off of the control or conventional operation.
It would be rather awkward here if you had to enter a certain
numerical value for each possible combination.
It is easier for you if you image that there are 8 switches in the
relevant CVs that can be switched on and off. We call these
switches "bits". If the switch is switched on, we say "the bit is set"
or "the bit is 1"; if the switch is switched off, we say "the bit is
deleted" or "the bit is 0".
This is only a different way of writing numerical values, called
binary presentation. In this system the numerical value is not
shown using the figures 0,1,2,3,4,5,6,7,8,9, but using only the
figures 0 and 1.
Example: binary presentation of CV29
A variety of settings are saved in this CV. Whether a certain
setting is switched on or off, is determined by one of the 8
switches (bits):
Switch
no.
Switched on (=bit set "1") Switched off (=bit deleted "0")
1 (0) Locomotive runs backward if
direction switch points 'up'
Locomotive runs forward if
direction switch points 'up'
2 (1) Locomotive runs in 28/128 running-
notches mode
Locomotive runs in 14/27
running- notches mode
3 (2) Locomotive can also run analogue Locomotive cannot run
analogue
4 (3) Not used Not used
5 (4) Decoder uses the set characteristic
speed line
Decoder uses the default
characteristic speed line
6 (5) Locomotive controlled via extended
address from CV17 and CV18
Locomotive controlled via
basic address from CV1
7 (6) Not used Not used
8 (7) Not used Not used
Certain features are simply switched on and off by setting or
deleting a bit in the CV.

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The setting and deleting of individual bits is particularly easy with
the manual controls LH100 (from version 2 on), LH200 and
LH90. These devices have a menu designed specifically for this
purpose.
If you use a LH100 of a version smaller than 2, you will not be
able to program in the binary mode. The same is true for the
"compact" and possibly devices of other manufacturers. In this
case you will have to enter a decimal number in the CV which
corresponds to the set or deleted bits. For more information
please refer to the Appendix, Section "Bits and bytes -
conversion help”.
3.3.1 Counting principles of bits
In the engineering field it is common to start counting bits from 0
onwards. Since this does not correspond to normal linguistic
use, we start counting bits with 1 (you don’t count the coaches of
your train starting 0, 1, 2, do you?). This method applies to all
Digital plus devices and decoders. When programming your
decoders with devices of other manufacturers, you may have to
start with 0, therefore we have put the number for the counting
method starting from 0 in brackets behind the bit numbers.
Example:
Bit 2 (1): The number in front of the brackets represents the bit
number for the counting method starting from 1; the
number in brackets shows the bit number starting
from 0.

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4 Installation
4.1 Preparations and tests before installation
Before installing a Digital plus decoder, check the locomotive in
normal DC operation to ensure that it works correctly before
modifying it. Replace worn wheel contacts, motor brushes and
blown bulbs. Only a locomotive that is mechanically OK will
function properly with a locomotive decoder.
4.2 Affixing the decoder
Under no circumstances may the parts of the locomotive
decoder be allowed to touch the metal components of the
chassis or the body of the locomotive as this could cause a
short-circuit within the locomotive decoder leading to damage.
Never wrap the locomotive decoder in insulating tape as this
prevents the necessary air circulation around the decoder.
Instead, use insulating tape or something similar around the
metal components of the locomotive to avoid unintentional short-
circuits without depriving the decoder of air. If a heat-shrink
sleeve (insulating sleeve) is installed ex-works to protect
components that are sensitive to contact, this sleeve may not be
removed (warranty loss).
Use double-sided adhesive-tape to affix the decoder (enclosed
with the product).
4.3 Locomotives with interface
Here, installation is particularly easy. The NEM652-conform
interface plugs facilitate quick and easy conversion of
locomotives.
Pull the strapping plug off the locomotive’s interface and keep it
in a safe place. Now, plug the decoder’s connector onto the
interface so that Pin 1 is placed at the position shown in the
operating manual. When installing the plug, ensure that the pins
are not bent or broken.

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Pin assignment of the NEM652 interface:
Pin Meaning
1 Motor connection 1
2 Function output B
(rear headlight)
3 Function output C
4 Left rail pickup
5 Motor connection 2
6 Function output A
(front headlight)
7 Function positive common
8 Right rail pickup
Orange Pin 1
The orange cable
indicates the
position of Pin 1 on
the plug.
In the case of decoders that have more function outputs than A,
B and C, these outputs are designed as loose cables to be
soldered.
4.4 Locomotives without interface
Please note which motor connection is connected to the right rail
pickups and which to the left. If you do this you will not have to
try out which decoder cable needs to be soldered to which motor
connection to achieve the desired direction of travel when
connecting the decoder.
After removing the original connections to the motor brushes, the
motor brushes must be potential-free. This means that they are
not be connected in any way to the chassis or the rail pickups of
the locomotive. This should be checked using a meter with a
‘buzzer'.
Bear in mind that a such a connection is sometimes made only
when the chassis is put back! Remove condensers which are
connected across the motor brushes.
Please contact a service centre if you are in any doubt as to
whether all necessary preconditions for the installation are
fulfilled!

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4.4.1 Cable colours
The cables of all SILVER decoders follow the same colour code.
Having connected one decoder, you will know exactly what to do
the next time.
Cable colour code:
red Track connection, right-hand side
black Track connection, left-hand side
orange Motor, one connection
grey Motor, the other connection
white Function output A, lights at front for direction-dependent
lighting
yellow Function output B, lights at back for direction-dependent
lighting
green Function output C
purple Function output D
blue Function positive common
4.4.2 Motor and track connection
If you separate the track and motor connection while installing
the locomotive decoder, please note which track connection
belongs to which motor connection. Please wire as follows:
Red track connection belongs to the orange motor connection
Solder the red cable to the right track connection and the orange
cable to the motor connection which was previously connected to
the right track connection.
Black track connection belongs to the grey motor connection
Solder the black cable to the left track connection and the grey
cable to the motor connection which was previously connected to
the left track connection.
For the ABC module and the conventional operation to work
properly, observe the following when connecting the track and
motor:
If you are operating a steam locomotive and you are looking
from the driver’s cab to the smoke stack while the locomotive is
moving forward (i.e. the smoke stack leads), the red cable of

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the decoder must be soldered to the right-hand current
collector.
4.4.3 Function outputs
You can connect bulbs, LEDs, relays, smoke generators or even
a remote coupling to the function outputs. Always ensure that the
connected function does not consume more power than the
respective function output of the decoder can supply. If this value
is exceeded, the output will be damaged.
If you wish to connect LEDs to the function outputs, ensure that
the function output is "negative". The LED’s cathode must be
connected to this function output via a voltage multiplier. The
LED’s anode must be connected to the blue cable, as this is the
decoder’s "positive" side.
There are two ways of connecting functions to function outputs:
1. One connection of the function is connected to the function
output, the other to the decoder’s blue cable.
You must ensure that the functions inside the locomotive are
potential-free, i.e. that their only live connections are to the
decoder’s function outputs.
In this connection, the voltage at the function outputs (and
thus at the functions) is approx. 1.5 V lower than the track
voltage. The blue cable is the "positive pole" and the function
output is the "negative pole". This and the voltage multiplier
are particularly important when connecting LEDs.
2. One connection of the function is connected to the function
output, the other to a track connection.
This is how the lighting of many locomotives works. The
bulbs are directly connected to the locomotive’s chassis
which in turn is connected to one side of the track. For
functions connected like this, the blue cable remains
unused. Thus, the wiring is a little easier, but the resulting
voltage for the bulb is halved. This means the lighting is a
little darker than is the case when the blue cable is used.
In this type of connection, the lighting will still only work in
one direction of travel in conventional operation. Which
direction this is depends on which side of the track the
chassis is connected to.

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5 Setting the address
SILVER decoders can be operated both with the basic
locomotive address in CV1 (range 1-127, the Digital plus system
only uses addresses 1-99) as well as with the so-called extended
locomotive address (range 100-9999), stored in CV17 and
CV18.
For the locomotive decoder to know to which address it is to
react, Bit 6 in CV29 serves as a switch between the two
addresses. If this bit is deleted (0), the 2-digit address from CV1
will be used; if this bit is set (1), the 4-digit address from CV17
and CV18 will be used.
When using the Digital plus command stations LZ1001or
LZV100 together with a manual control LH100 or LH90 for the
programming of the address, you will not have to pay attention to
this division into the different CVs. Simply enter the desired
address via the menu "Programming on the programming track".
Enter the 2 or 4-digit address; the rest will be done automatically
by the system.
When using a compact or LZ100 up to version 2.3, you will only
use 2-digit addresses. In this case, you always enter the address
in CV1.
If a valid address is entered in CV1, Bit 6 in CV29 is
automatically deleted and the decoder set to operation with a 2-
digit address.
Ex-works SILVER decoders are set to address 03.
If, by mistake, an address greater than 127 is entered in CV1,
the SILVER decoder will automatically change the address to 03.
1from version 3 on

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6 Setting the motor control
SILVER decoders are equipped with a control (load
compensation). A set speed is thus held constant (so far as
technically possible) independent of larger or smaller loads.
Since the different models are equipped with different motor
types, the characteristic can be adjusted to the control.
6.1 Selecting the motor type
In order to also facilitate this adjustment for model railway
operators who are not control engineering experts, we have
combined different settings to so-called "motor types". It is thus
possible to select between different types without having to pay
attention to the precise setting of the control parameters.
If the control behaviour of the standard setting (motor type 0) is
not ideal for your model, simply try a different motor type. Motor
types 0 to 3 have set control parameters.
The motor type is set in CV50. Ex-works, CV50 is set to 0, i.e.
motor type 0. If you wish to select a motor type 0 to 5, enter the
respective value 0 to 5 in CV50.
Motor types 4 and 5 provide for 2 further CVs which make fine-
tuning possible.
Advice on how to proceed:
First, set the motor types 0 to 3 one after the other and check
the result. If you are unhappy with the result, try motor type 4.
Then alter the value in CV113 and CV114 until you achieve the
desired result. Never alter the motor type and the value in
CV113 and CV114 simultaneously!

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6.2 Switching the control on and off
If you wish to completely switch off the decoder’s control, set Bit
7 in CV50. The previously selected motor type will no longer
have an effect; the same is true for the EMF switch.
6.3 Switching off the high-frequency control
To keep the noise emission to a minimum, the control operates
in a high-frequency range. Some models do not show
satisfactory control behaviour when operated with the high-
frequency control. In this case, you can switch to low-frequency
control by setting Bit 8 in CV50 in addition to setting the motor
type.
6.4 Activating the EMF switch
The decoder still has a so-called EMF switch which makes it
possible to adjust the decoder to different motor types.
Depending on the motor type used, it is possible that a digitally
controlled locomotive cannot reach an adequate maximum
speed compared to a locomotive in conventional operation. If
this is the case, activate your EMF switch by setting Bit 6 in
CV50. The locomotive will then reach a higher maximum speed
while the minimum speed is also slightly increased.
6.5 Repeat rate
Another possibility for adjusting the control is to set the repeat
rate in CV9. Depending on the motor type used, changes in this
CV will be more or less apparent.

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7 General settings
General settings for the SILVER decoder are carried out in
CV29. Features in this CV are assigned to individual bits. This is
why it is best to carry out changes in this CV in the binary mode
of the manual controls LH100 and LH90.
When using devices that do not support the individual setting
and deleting of bits, you must enter a decimal number in the CV
that corresponds to the set or deleted bits. Further information
can be found in the Appendix, Section "Bits and bytes -
conversion help"
CV29:
Bit Setting
1 (0) Direction of travel
0 normal: locomotive drives forward if the arrow on the manual
control points up.
1 interchanged: locomotive drives forward if the arrow on the
manual control points down.
2 (1) Running-notches mode:
0 Operation with 14 or 27 running notches.
This setting is chosen when using a decoder together with
digital systems which do not support the 28/128 running-
notches mode.
1 Operation with 28 or 128 running notches.
This setting is chosen when using a decoder together with
digital systems which support the 28/128 running-notches
mode.
3 (2) Operational mode analogue / digital:
0 Locomotive only runs in digital operation
1 Locomotive runs both in digital and conventional operation,
flying splice possible.
Please find further information on the system change from
analogue to digital operation further below in this section.
4 (3) Not used
5 (4) Characteristic speed line:
0 Default characteristic speed line is used
1 Self-programmed characteristic speed line is used. Please
enter suitable values in CV67 to 94 before setting this bit.
Please find further information on the characteristic speed line
in the Section "Characteristic speed line", page 26.
6 (5) Address used
0 Decoder uses basic address (from CV1)
1 Decoder uses extended address (from CV17 and CV18)
7-8(6-7) Not used

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7.1 System change during analogue operation
All SILVER decoders can be operated on conventional layouts
with traditional DC devices. If Bit 3 is set in CV29, a locomotive
equipped with a decoder will behave in conventional operation
like a locomotive without a decoder. However, a starting delay
programmed in the decoder can be used.
Even a flying splice between a digital and a conventional layout
section is possible. Here, the locomotive will behave as follows:
7.1.1 Change from digital to conventional
During a change from a digital layout section to a conventional
section, the locomotive decoder follows the polarity of the
conventional section. If the polarity of the section (and the
resulting direction of travel according to NEM) matches the
direction of travel in the digital section, the locomotive will
continue without stopping. However, because the speed
depends on the voltage applied in the conventional section,
variations in speed are possible.
If the polarity does not match the direction of travel, the
locomotive will stop following the braking delay set in the
locomotive decoder.
When the model railway is in operation, this behaviour can be an
advantage when stopping in front of signals. Simply add a
separate braking section in front of a signal, which is supplied
with direct current if the signal is "red". The current’s polarity in
the direction of the signal is set so that the locomotive stops. If
the signal is passed in the opposite direction, the locomotive will
drive through despite the red signal. A disadvantage is the
possible variation in speed which may occur during the change.
To find out how this can be avoided, please refer to the Section
"System change with switched-off analogue operation", page 20.
A relevant example is contained in the operating manual of the
sectioning model LT100 which is necessary for the transition
from digital to analogue operation and vice versa.
7.1.2 Change from conventional to digital
If a locomotive changes from the conventional layout section
back to the digitally controlled area, the locomotive decoder will
again be able to receive digital information. As in the case of the
example above, different reactions of the locomotive are
possible:
If the direction of travel transmitted by the Digital plus by Lenz ®

20
command station matches the locomotive’s present direction of
travel, the locomotive will also take over the speed transmitted
by the command station and thus continue driving.
If the actual direction of travel does not match the direction of
travel transmitted by the command station, the locomotive will
stop with the set braking delay, change its direction of travel and
continue in the opposite direction, i.e. return to the conventional
section. There, it will stop.
If the locomotive is not called up in the digital layout section, the
address of the decoder will also not be sent. In any such case,
the locomotive will continue.
7.1.3 Why does the speed change during a system change?
The motor at the decoder output is operated with a so-called
pulse-width control. Here, the voltage is not altered depending
on the speed (low speed = low voltage; high speed = high
voltage), but the motor is charged with full voltage, if not for the
whole time. The rule that is applicable here is: low speed = short
turn-on time and long turn-off time; high speed = long turn-on
time and short turn-off time.
If the decoder-fitted locomotive now changes from digital to
analogue, it is possible that a low running notch (speed) is set.
The decoder recognises the analogue section and has to adjust
the pulse width to the maximum value so that the motor can
again be controlled analogue to the level of the track voltage.
This means that the locomotive speeds up if the conventional
voltage is as high as the digital voltage. If the conventional
voltage is lower than the digital voltage, the locomotive will first
slow down (since only little power is transmitted to the motor via
the pulse width) and then accelerate until the desired speed is
reached.
7.2 System change with switched-off analogue operation
You can avoid the disadvantage of the speed matching during
the transition from digital to conventional by switching off the
decoder’s conventional operation (delete Bit 3 in CV29). You will
no longer be able to operate the locomotive conventionally, but
its reaction during the system change will improve.
If you let the decoder change from the digital to the conventional
section when the conventional operation is switched off, the
locomotive will stop with the set braking delay.