Atlas 520099 User Manual

Decoder for Atlas N Scale H15/16-44 Locomotives

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The #520099 DCC decoder is designed for Atlas N scale H15/16­44 locomotives. The characteristics of this decoder are:

∗ Provides 0.5A continuous motor current.
∗ Has two function outputs with built-in white LED headlights that can be

configured for special effects including directional, independent, dimming,
Mars light, Gyro light, single Strobe, and double Strobe.

∗ Provides two additional function outputs with built-in bi-color LEDs that

provide directional green or red marker lights at front and rear and can be
configured for on/off control by a specified DCC function.

∗ Supports both short (2-digit) and long (4-digit) addressing.
∗ Supports advanced consist control (lashing up locomotives that have

different DCC addresses)

∗ Operates on conventional DC layouts; this feature may be disabled by

setting a CV.

∗ Provides full support for all forms of programming that are described in

NMRA RP-9.2.3.

∗ Supports both short form instructions and long form instructions in

operations mode programming (programming on the main line)

∗ Can be set for operation with 14/27 speed-steps, 28/55 speed-steps, or 128

speed-steps with direct drive.

∗ Can choose either Precision Glide Control or Silent Drive for motor control

DCC Decoder for Atlas N
Scale H15/16-44
Locomotives

Item # 520099
Revised 09/14/2004

Atlas Model Railroad Co., Inc.

Decoder for Atlas N Scale H15/16-44 Locomotives 2

N Scale H15/16-44 DCC Decoder

The N-scale H15/16-44 DCC decoder can be used with all popular
NMRA-compliant DCC systems. This decoder is in full conformance with
all NMRA Standards and Recommended Practices and has been
augmented to work well with all major DCC systems on the market.

The N scale H15/16-44 decoder is packed with all the features that you
expect in a high-end decoder:

• Special lighting effects for front and rear headlights including
directional, independent, dimming, Mars light, Gyro light, single
Strobe, and double Strobe.

• Directional bi-color (green and red) front and rear marker lights.

• Supports both short (2-digit) and long (4-digit) addressing.

• Advanced consist control (operating and controlling several

locomotives as if they were a single entity by sending speed and
direction commands to a common consist address that is stored in
the decoder of every locomotive in the consist).

• Operations mode programming (programming on the main line).

•

Full support for all the various motor speed-step modes, including
the 128 speed-step mode

•

Choice of either Precision Glide Control or Silent Drive for motor
control.

Many characteristics of the H15/16-44 decoder can be programmed to
customize the decoder to its locomotive. Please read The Configuration
Variables and their Definitions section for details on the configuration
variables supported by the H15/16-44 decoder. The H15/16-44 decoder
supports all forms of programming described in NMRA Recommended
Practice 9.2.3, including the user friendly direct CV (Configuration
Variable) programming mode and operations mode programming. For
example, you can operate the decoder with the factory-default speed
curve, or you may specify your own customized speed curve. You can
also set which end of the locomotive is to be the forward end. You can
even decide whether or not you want to be able to operate the
locomotive on conventional DC layouts. If your DCC system supports
operations mode programming, you can change the values of all CVs

(except for the locomotive’s 2-digit, 4-digit, and consist addresses
in CV1, (CV17 and CV18), and CV19; respectively) while the

locomotive is on the main line.

.

Atlas Model Railroad Co., Inc.

Decoder for Atlas N Scale H15/16-44 Locomotives

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Lighting Options for the H15/16-44 Decoder

The H15/16-44 decoder has four function outputs: A, B, C, and D.
Decoder outputs A and B are designed to control the white LEDs used
for the front and rear headlights, respectively, in these locomotives. The
front and rear headlights can be configured by Bit 0 in CV51 to be either
directional or independently controlled. It is also possible to dim, using a
DCC function, either directional headlights or independently controlled
headlights.

If the headlights are configured for independent control, the front
headlight may be configured with the appropriate bits in CV51 to operate
as a Gyro light, a Mars light, a single pulse Strobe light, or a dual pulse
Strobe light. Similarly, when the headlights are configured for
independent control, the rear headlight may be configured with the
appropriate bits in CV57 to operate as a Gyro light, a Mars light, a single
pulse Strobe light, or a dual pulse Strobe light.

Decoder outputs C and D are designed to control the bi-color LEDs
used for the front and rear marker lights in these locomotives. Decoder
outputs C and D are auto-reversing so that the bi-color LEDs show
green in the direction that the locomotive is traveling and red in the
opposite direction. The only control over these marker lights is on or off.
By default, function F2 is used to turn these lights on or off. If desired,
this default setting can be changed simply by modifying CV54; by writing
the proper value into CV54, the marker lights can be switched on or off
by any function F1 through F8. If you are using a DCC system where
function F2 is momentary (e.g., Digitrax), it is recommended that you
remap F2 to another function with on/off control.

If you are using an NCE Power Pro DCC system, you will need to
change the values of two parameters in your command station to get
proper operation of the H15/16-44 directional marker lights. The Number
of Temp Packets must be changed from 5 to 8, and the Function Repeat
Rate must be changed from 0 to 250. Refer to the NCE System
Reference Manual for instructions on how to change the values of these
parameters.

The H15/16-44 decoder comes with two white LED
headlights and two bicolor marker light LEDs already
installed. The light outputs of this decoder are designed
only to drive these four LEDs. The Atlas warranty is void if
any of these LEDs are removed from the H15/16-44 circuit
board.

Atlas Model Railroad Co., Inc.

Decoder for Atlas N Scale H15/16-44 Locomotives 4

Silent Drive or Precision Glide Control

The H15/16-44 decoder provides an option to use either Silent Drive or
Precision Glide Control for motor control. Silent Drive is best for
coreless motors and for applications were you want absolutely silent
operation. Precision Glide Control provides much more precise slow
speed operation because it pulses the motor to ensure the friction of the
motor and drive train does not interfere with the operation. The default is
Precision Drive Control. The motor control selection is made using
CV50.

Preparing to Install the H15/16-44 Decoder

Before installing the H15/16-44 decoder in your locomotive, it is
necessary to test (and adjust, if necessary) the locomotive for proper
operation on conventional DC power. Replace any worn out parts, such
as brushes. Also clean any dirt or oxidation from the wheels and pickups
to insure that electrical contact is good. Now is also a good time to
lubricate your locomotive. A locomotive that runs well under
conventional DC will also run exceptionally well under DCC.

Precautions to Take When Installing the Decoder:

Although the H15/16-44 decoder has many internal safeguards to
prevent damage, you must not allow any metal part of the locomotive to
touch surface components of the decoder other than the pickup pads on
the decoder that connect to the wheel-sets, the headlights, and the
motor. Any contact to other parts of the decoder can cause a direct

internal short circuit and destroy the DCC decoder.

The H15/16-44 decoder is not completely protected against static
electricity and has sensitive electronic parts. When installing this
decoder in your N scale locomotive, it is recommended that you wear a
grounded anti-static wrist strap. Also be careful in handling the decoder,
especially in the area around the top rear part of the decoder (the area
where the microprocessor is located).

Atlas Model Railroad Co., Inc.

Decoder for Atlas N Scale H15/16-44 Locomotives

Step by Step Installation

Figure 1: Installing the H15/16-44 decoder

In the following steps, please refer to the instructions provided with your
Atlas locomotive.

1) Remove the locomotive's body shell and fuel tank. Use care so as
not to damage any of the fragile parts.

2) Loosen the two screws that hold the frame together; these screws
are located at the front and rear of the frame.

3) Carefully remove the lighting control circuit board, which is located
at the top of the frame.

4) Place the decoder between the two halves of the frame so that the
two motor contact pads are at the bottom of the decoder and will
press firmly against the two copper contact strips from the motor
when the decoder installation has been completed. In the
photograph of the bottom of the H15/16-44 decoder on the first
page, these motor contact pads are the two rectangles in the
narrow center portion of the circuit board.

5) Carefully press the two frame halves together, with the sides of the
decoder inserted into the notches in the two halves of the frame.
Some pressure is needed to press the two frame halves together.
This pressure fit insures good electrical contact between the frame
and the decoder.

6) Tighten the two screws that hold the locomotive frame together.

7) Carefully check to make sure that the motor contact strips are not
touching either half of the frame. It is necessary to look down from
the top through the frame cutouts to check for such unwanted
shorts.

There must be NO electrical contact between the motor
contacts and any part of the frame

Place the locomotive (without its body shell) on your DCC programming
track and read back the locomotive's address from the decoder. If the
decoder is properly installed, you will be able to read back the factory
pre-set address 03. If your DCC system does not support reading

Atlas Model Railroad Co., Inc.

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Decoder for Atlas N Scale H15/16-44 Locomotives 6

decoder properties, observe carefully the decoder's behavior while on
the isolated programming track. Each time you try to program the
decoder you can see the acknowledgement that is sent by the decoder
in the form of a brief and minor jerk of the locomotive. A successful
acknowledgement means that you have installed the decoder correctly.

Remove the locomotive from the programming track and, if necessary,
correct any installation errors. Once you have successfully programmed
the decoder, reinstall the body shell and retest the locomotive on the
programming track. If this test is successful, the locomotive is ready to
use.

Programming the H15/16-44 Decoder

The H15/16-44 decoder supports all forms of both service mode
(programming on an isolated programming track) and operations mode
programming (programming on the main line). Using any of these
programming methods, many features (such as the locomotive's
address, acceleration, and configuration) can be customized to the
individual locomotive in which the decoder is installed. These
customized properties will be saved in non-volatile memory locations on
the decoder so that they will retain their values even after power has
been removed. All parameter values are set electronically, which means
that the locomotive does not need to be opened again after the decoder
has been installed to read or modify the values of these so-called
Configuration Variables (CVs). The H15/16-44 decoder has a total of
128 CVs. Not all of them are used at this time because many have been
reserved for future use.

Any NMRA-compliant DCC Command Station, such as the Atlas Master
Commander, can be used to program the H15/16-44 decoder. With
several entry-level systems, only CV #1 (the locomotive address) can be
set unless you use a separate DCC programmer. More advanced DCC
systems, including the Atlas Commander, support the ability to set many
more CVs. The H15/16-44 decoder supports all programming modes
and can be programmed by all NMRA-compliant DCC systems. The

locomotive’s 2-digit and 4-digit addresses in CV1, CV17, and CV18
CANNOT be programmed in operations mode. Instructions for

reading and writing CVs are given in the user manual of your DCC
system.

Note: for newly programmed CV values to take effect after service
mode programming, the decoder must go through a power reset. If
your DCC command station does not support automatic power
reset, simply rock the locomotive off the track after programming.

Atlas Model Railroad Co., Inc.