Non-Sound Decoder MX600 - MX634 and Sound Decoder MX640 - MX658 Page 51
Locomotives with 6 or 8 pin NMRA interface . . .
. . . are easy to retrofit with the MX...
R
, MX...
F
, MX...
N
(e.g. MX630R or MX620F) etc. They come
with the appropriate 8 (R) or 6 (F, N) pin connector. There is usually enough room provided in such
locos. Removing the dummy plug from the loco automatically interrupts all damaging connections and
the decoder can be plugged in instead.
In some cases it is necessary to hardwire some decoder leads besides just plugging in the plug. An
example of this is the MX630R that has more outputs available than the standard 8-pin plug has pins.
For hard-wiring of decoder leads use the explanations below.
Hard-wiring a loco
motive…
… with a DC motor and headlights:
This represents the
most common wiring diagram
for HO installations. All other diagrams that fol-
low are modified or extended versions of this one.
Red
Black
Orange
blue
Yellow
White
Gray
Right rail
Left rail
M
Headlights
Rear Front
DC Motor
Right
Left
Headlights connected as shown on this diagram are directional and switched on/off by the F0 key.
With the appropriate use of "function mapping" - CV's #33, 34, 35...
– it is also possible to control the
headlights independently with F0 and F1.
PLEASE NOTE: Body mounted light bulbs that are hard to isolate can be left as is. The body acts as
the power supply to the bulb. The blue lead from the decoder must not be connected to the bulbs in
such circumstances. The white and yellow leads are connected to the other side of the bulbs. The
brightness of the headlights will be reduced with such an application
. . . with an AC motor:
Two additional 1N4007 diodes (or equivalent) are required as shown in the diagram below when in-
stalling a decoder in a loco equipped with an AC motor. They can be obtained at your local electronic
store or from ZIMO.
Red
Black
Orange
Blue
Yellow
White
Gray
Right rail
Left rail
M
Headlights
Rear Front
AC-m otor
Field coils
2 Diodes 1N4007
Rotor
Most locomotives with AC motors get the power supplied by a third rail, which is of no significance as
far as the motor hook-up is concerned. The above schematic is therefore valid for AC locomotives
running on two or three rail track (instead of “right rail” and “left rail” think “outside rails” and “center
rail”).
Note: many locomotive manufacturers supply field magnets that can be used in place of the motor’s
field coil. Using a field magnet turns an AC motor into a DC motor, which is connected as such (see
above) and can also utilize the decoders BEMF feature (BEMF does not work with AC motors).
Additional hook-up for cab lighting controlled with F0 key:
This is no longer of much use today; it is a remainder from a time when decoders only had two func-
tion outputs, which were used for the headlights and the cab light. Cab lights connected this way can
be switched with the F0 key but in contrast to the headlights were non-directional.
This is however a general schematic that can be used in cases where something is to be operated by
several different function outputs, but the same outputs used independent of each other. There are 2
diodes required (type 1N4007 or equivalent) available from ZIMO or any electronic parts supply store.
Blue
Yellow
White
Headlights
Rear Front
2 Diodes
1N4007
Cab light bulb
Connecting function outputs FO1, FO2, FO3, FO4…:
Depending on decoder type, function outputs FO1 and higher are available on wires, solder pads or
part of a connector (i.e. the MX620 offers FO1 and FO2 on solder pads, the MX630 and MX632 on
wires and further outputs on solder pads) and can be connected in the same fashion as headlights.
For mapping the outputs to function keys, see chapter 5; the function outputs FO1 and FO2 are
mapped by default with function keys F1 and F2.
Also see note on MX632 below!
Red
Black
blue
Yellow
White
Solder pad FO1
Right rail
Left rail
Headlights
Rear Front
E
.g
.
C
a
b
l
ig
h
t
Using logic level outputs:
ZIMO decoders also have so called logic level outputs in addition to the normal function outputs, to
which current consuming devices may not be connected directly. Use a ZIMO M4000A amplifier or
similar transistor switching device, when connecting logic level outputs with a load.
Some logic level outputs are used alternatively for the “SUSI-CLOCK” and SUSI-DATA” connections
and can be switched to logic level outputs when setting CV #124 Bit 7 = 1 (if SUSI is not required).
Furthermore, the same pins can be used for servo control (activated with CV’s #181 & 182).
NOTE on MX632:
The logic level outputs FO5 and FO6 of the MX632 are identical in their function as
the amplified outputs FO5 and FO6 (not FO7 and FO8 as was first announced erroneously); however,
if
“SUSI” (CV #124, Bit 7) or servo control (CV’s #181, 182) is active, neither the amplified out-
puts FO5/FO6 nor the logic level outputs FO5/FO6 will be functional!!
The brown lead of an
amplifier module M4000Z
is connected with the relevant logic level output sol-
der pad of the decoder.
