User Manual
INSTALLATION
If your loco has an NMRA DCC 8 pin socket or 9 pin plug, all you need to do
is plug in the decoder. Otherwise you have to cut the 8 pin plug and wire in
the decoder. It is quite a challenge to install a decoder into a locomotive
without the DCC socket. You should have some basic electrical knowledge
and soldering skills. If you do not have the above requirements, please ask
the dealer for help in installation.
Figure 1 shows the electrical circuit of most standard locomotives. The
terminals of the motor and lights are directly connected to the wheel pick-
ups. Each type of loco has its own method of electrical pickup. The con-
nection between wheel and motor/light could be wires, clips, the body or
any conductor. Figure out your locomotive’s electrical connection and how
to disconnect (isolate) the motor and lights. The decoder will be inserted
between the wheel pickups and the motor. The ‘X’ marks in Figure 1 show
you where to disconnect.
Figure 1. Connection of a standard locoNote: The ‘X’ signs indicate
where to disconnect (isolate)
Figure 2 shows you how to wire the decoder. After disconnecting the motor
terminals from pickups, connect the red wire to the right side pickup and
the black wire to the left side pick up. Connect the orange wire to the motor
terminal that originally connect to the right pickup. Connect the gray wire to
the motor’s other terminal. Connect the front light to the blue wire and the
white wire. Connect the rear light to the blue wire and the yellow wire.
The blue wire is the common terminal for headlights and accessory func-
tions (ACC1 & ACC2). You may use the black wire or the red wire to re-
place the blue wire. This is very useful when you find that it is hard to
isolate one of the light terminals from the pickup. Wiring the bulb this way
will also make the light dimmer. If your loco has only a front light, you
should connect the white and the yellow wires together.
TEST
All MRC decoders have been factory programmed with address #3, 28/128
speed steps and maximum top voltage. After you have finished your de-
coder installation, you are ready to test it. Never run the installed decoder
on your layout without first passing the test. You may damage the de-
coder if it is not wired correctly or if you have not properly isolated the motor
and the lights.
Put the loco on the test track. Select the Run Mode of your DCC system and
select or acquire address #3. Move up throttle and the loco should move
forward. Push the light button and the front light of your loco should turn on.
Push the reverse direction button. The loco should move backward and the
rear light should turn on. The loco cannot get to normal speed because
there is a 20 ohm protection resistor in the test track. If you are able to turn
on/off the front and rear lights and you are able to move the loco in forward
and reverse, you did a great job. Congratulations! Do not test the loco on
the test track for an extended period of time. To do so will cause the
protection resistor to overheat.
MAKE A TEST TRACK
Before you start with your decoder installation, we strongly recommend
building a test track which uses a 20 ohm resistor to limit current. Only test
your installed decoder on the test track. The test track will prevent any
damage due to an incorrectly wired decoder.
OPERATION
Headlight
There are three ways to operate headlight (depends on CV60):
1. Normal directional lighting (CV60=0)
2. Rule17 lighting (CV60=1). One light is bright to indicate direction
of travel, the other is dim.
3. Both front and rear headlight on / off at the same time (CV60=2).
ACC1 &ACC2 LIGHT EFFECTS:
There are two function output wires (green and pink) on the decoder.
Their functions are controlled by CV112 (green) and CV113 (pink).
See the CV112&CV113 chart.
Note: Ditch lights will use two lights. Both CV112 and CV113 must be
programmed to 0. To turn on/off ACC1&ACC2 use F3.
Please refer your DCC manual to learn how to program CV. See the
register/CV chart to custom tailor your MRC Light Effects. For a more
comprehensive understanding of CVs and registers. visit the National
Model Railroad Association website at www.nmra.org.
Figure 2. Decoder wiring diagram
If your installed decoder does not pass the test, find the problem, cor-
rect it and test it again. As long as you test the decoder on the test track
there is little chance of damaging your decoder. This is why making a
test track is so important.
Right side pickup
Front
light
Motor
Rear
light
Left side pickup
X X X
X
X
X
black
white
left
right
orange
gray
Motor
blue
red
yellow
rear light
front light
ditch light
strobe light
mars light
ditch light
DCC base unit
Power supply
Test track
20 ohm resistor
NMRA DCC plug
green wire
pink wire
9-pin plug
Green wire Pink wire
CV112 CV113
Ditch 0 0
Gyra 1 1
Mars 2 2
Prime Strato 3 3
Single Strobe 4 4
Double Strobe 5 5
Light Type