User manual

Connection of contacts:
1. Three-conductor rail-system
At the feedback module RM-88-N all contacts can be connected
which are switching against ground (mostly digital wire
“brown”).
Therefore is it possible to switch against the feedback module
connection clamp marked ⊥ or against the connection 0 (brown)
of the rails.
Switch rails, contact rails and reed-contacts can be
connected to the clamps 1 to 16 as shown below.
Type of contact
1 2 3 4 1 2 3 4 1 2 3 4
Schaltgleis
Kontaktgleis Reedkontakt
Kontaktart
switch track contact track
reed contact
At section 2 (two-conductor rail system) you can find an
additional possibility to connect reed-contacts. The second
connection of the reed-contact will not be soldered to the
connection 0 of the track but connected to the ground clamp ⊥
at the feedback module.
All shown above connections are conform exactly to the known
wiring of the Märklin feedback module s88.
Further sample connections can be found at the Internet on our
Web Site (www.ldt-infocenter.com) at the section “Downloads”
and “Sample Connections”.
Beside the single sample connections we recommend the file
“RM-88_Info” within the section “Downloads”.
To avoid interferences and wrong occupancy reports by
feedback module, which are switching against ground, is it
recommended not to install the connection cable to the 16
inputs together with digital current carrying cables (e.g. common
cable channel).
If the connection cables to the contacts are very long and
installed very narrow (e.g. within one cable with several wires) it
can even come to some signal transfer between two wires.
Although only one section is actually occupied several sections
can be reported to be occupied.
But also the particularly simple track occupied report from
contact rails (one isolated rail) can initiate problems because
the isolated rail runs inevitable parallel to the digital current
carrying middle conductor.
As longer a contact track as sooner interferences are possible.
As a result the input can be switched temporarily to be occupied
although no train is on the respective track section.
The described problems can be solved by using interference
suppression diodes or decoupling diodes before the single
inputs. A sample wiring can be found on our Web Site at the
section “Sample Connections”.
Alternative is it possible to use the feedback module RM-88-N-
O that is less sensitive against interferences due to opto-
coupling inputs.
2. Two-conductor rail-system:
If you use reed contacts or other potential-free contacts for
feedback signals on your layout you can install the wiring to the
feedback module RM-88-N as shown at the below circuit.
1
2
3
4
Reedkontakt
reed contact
Even the shortest switch impulses will be transferred by the
feedback module RM-88-N because they will be stored via the
s88-feedback bus until the digital control unit or the interface
will request this information.
Feedback module from our Digital-Professional-Series are
easy to use on your digital model railroad, as they are 100%
compatible with the s88 feedback bus.
Accessories:
For safe installation of the feedback module below your model
layout we offer an installation set under the order code MON-
SET and for the assembled kits a sturdy exact matching case
(order code: LDT-01).
Further products from our Digital-Professional-
Series:
RM-88-N-O
16-fold feedback module with integrated opto coupling-
inputs for the s88-feedback bus.
RM-GB-8
8-fold feedback module with integrated occupancy
detectors for the s88 feedback bus.
S-DEC-4
4-fold turnout decoder for 4 magnet accessories with free
programmable decoder addresses and possible external power
supply.
M-DEC
4-fold decoder for motor driven turnouts. For motors up to
1A. With free programmable decoder addresses. Drives can be
connected directly with the decoder output.
LS-DEC
Light signal decoder for up to 4 LED train signals. Signal signs
will be originally dimmed up and down and directly positioned
via the decoder address.
Made in Europe by
Littfinski DatenTechnik (LDT)
Kleiner Ring 9
D-25492 Heist/Germany
Phone: [phone] / 977 381
Fax: [phone] / 977 382
Internet: http://www.ldt-infocenter.com
Subject to technical changes and errors.  02/2013 by LDT
Märklin and Arnold are registered trademarks.