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A short circuit from motor brushes or ancillary outputs
to pickup shoes, frame, or wheels may destroy the device!
Installation of the loco-decoder 74400
Motor connections
Connect the red wire to the loco current
pickup which - when the loco is sitting on
the rails - is in electrical contact with the
right rail (right as judged by the engineers
view: looking from inside the loco towards
the loco front). Connect the black wire to
the current pickup which is in electrical
contact with the left rail. Connect the oran-
ge and the gray wire to the two brushes of
the motor: the orange wire should go to the
brush which, prior to decoder installation,
was in contact with the right rail. The other
brush (the left one) should be connected
to the black wire.
Important
: After installing the decoder all connections between rails and motor must be removed.
The motor must only be connected to the decoder gray and orange wires. RF interference
suppressors and capacitors should be retained.
Installation of an extra function
Connect the white and yellow leads to the front and rear lamps. The lamps return (common wire)
must be connected to the blue lead. Should either the driving direction or the directional lighting
come on wrong, then please swap, resp., the orange and gray leads on the motor or the white
and yellow wires feeding the lamps. If both the driving direction as well as the lights are wrong -
meaning that they agree with each other but they do not agree with what is shown to be forward
on the Command Station - then one can simply change the value of Bit #0 of CV #29 (without having
to resort to de/soldering).
Connect the white and yellow wires to each other if you wish them to work direction-independent
- that is, if you wish for the lights to always stay on independently of the loco driving direction.
The yellow and white wires can also be used to control other devices, e. g. a smoke generator.
Caution
Please take care to substitute any 12 V lamp with a 19 V one - or else lamps wont last long.
Fixing the unit in the model
Use the supplied adhesive pad for fixing the decoder in place within the loco. The pad keeps the
unit insulated and fixed at its position.
In case the loco has a high current consumption, we recommend to fasten the decoder directly
to the loco metallic frame using hot glue - all common brands are suitable for this. Please be
careful not to make any electrical contact between the loco frame and the decoder!
Safety first
Check for proper wiring after installation using a wiring checker or an ohmmmeter. Make sure
that the shell will not touch the unit and that no wires can be caught (pulled, cut) when loco
shell is placed back again on the loco frame.
black
Motor
orange
red
DCC
loco-decoder
white
blue
yellow
gray
driving direction
Connection 74 400