MX7E.pdf 59KB May 29 2006 05:56:01 PM - DCC Supplies

REVERSING LOOP MODULES MX7, MX7/3 Page 1
EDITION:
2003 02 15
Operating in struc tions
Re ver sing loop mo du les MX7, MX7/3
current version (from March 2002)

3 1
4 2
3 1
4 2
Page 2
REVERSING LOOP MODULES MX7, MX7/3
1. Allgemeines
By using a MX7 and isolating a sec ti on of track with gaps in both rails on either side
every reversing loop configuration (also turntables) can be wired and used without
any pro blems. The changing of po la ri ty in the reversing loop section is done very
quickly (within some microsecs) when the train is cros sing the gap and cau ses a
short circuit. The train con ti nu es running without any visible influence from the re -
versing loop; and it is al ways ful ly controllable by the cab.
The potentiometer allows to ad just the cur rent treshhold, which cau ses the auto -
matic change of polarity (and which is also the in di ca ti on for a real overcurrent con -
dition, which is assumed, when the current goes beyond the tres hold also after
some po la ri ty chan ges). In the lat ter case the out put LED is flashing.
Nor mal ly it is not necessary to modify the ori gi nal adjustment; for lar ge scales so -
me ti mes it is necessary to make a turn to the right side.
Triple reversing loop mo du le MX7/3:
This device con tains three ti mes the circuitry of the MX7. It is used for cases, when
not enough spa ce for a re ver sing loop section containing a full lenght of a whole
train is avai la ble. Then threee both-rail-gapped sec tions (instead of one) should be
built in such a way, that the pro ba bi li ty of crossing all four gaps at the same time is
very low. The usual way is to make one sec ti on in the lenght of a loco (or a con sist of
lo cos), and adjacent (on both sides) a short sec ti on (in the length of a bo gie).
2. Specifications
3. Track sections and con nec tions to MX7
Most simple way of use:
Jumper in right position (ex works)
C O M M A N D S T A T I O N M X 1 - B A C K V I E W
RS.232
CAN CAN
TRAFO
~ ~
Track outputs ....................................................... 3 A (Over cur rent pro tec ti on)
Track input (from the
command station)
Grund and pos. voltage,
to be connected with the
command station in order
to reduce the voltage drop
in the reversing loop track
section; obligatory in
certain cases.
Adjusting the treshold
for polarity change
(between about 2 - 4 A)
Jumper
right position (ex works) - ouputs supplied from track input
left position - outputs suppled from ground and pos. voltage
+
GROUND
Jumper
open (ex works); jumper should be used, if MX7 is used
after MX9, and MX9 shows wrong
occupancy state.
Outputs for 3 track sections;
LEDs showing current
polarity (red/green).
Contineous flashing means
short circuit because of
high current or bridging
all track isolations
simultaneously.
Flashing LED shows operation
of the module.
With addtional connection
of ground and pos. voltage:
C O M M A N D S T A T I O N M X 1 - B A C K V I E W
RS.232
CAN
CAN
TRAFO
~ ~
Jumper in left position

REVERSING LOOP MODULES MX7, MX7/3 Page 3
MX7 in a track triangle:
5.
If there is only little room
between the turnouts,
it must be avoided, that
both track isolations
are bridged simultaneoulsy
MX7/3 in a track triangle:
only one of the four track isolations
must remain free at
any time; if the distances of the
4 track isolations are arranged
cleverly, this is the case always.
5 cm
5 cm
(distance of car wheels)
40 cm
max. lenght of loco(s)
RS.232
MX7 used after track section module MX9:
CAN
CAN
3 1
4 2
N P
TRAFO
~ ~
MX9
Jumper in right position