
Installation
Tsunami2 and Econami Installation Guide 9
Step 3. Isolate Motor and Lights from the Frame
Note: If you have a DCC-ready model with an NMRA 8-pin connector, NMRA 9-Pin “JST”
connector, or 21-Pin “NEM” connector, proceed to page 15.
To ensure only the decoder’s motor outputs are driving the two motor connections, isolate the
motor connections from the locomotive frame, left rail, and right rail pickups. Many locomotives
are “DCC-ready,” and this step may not be necessary, though it varies depending upon the
manufacturer. Under Step 6. Install and Wire the Decoder, refer to “Installing into DCC-Ready
Locomotives” for more information regarding DCC-ready installations.
Note: Failure to properly isolate the motor may damage the decoder and we recommend
always practicing this step during the installation process.
To verify that the motor terminals are isolated from the chassis and rail pickups, refer to the
following procedure:
1. Make sure to have an ohmmeter or
continuity tester that you can use to
confirm that each motor terminal is
isolated.
2. Remove the body shell from the
locomotive (and the tender shell for
steam installations).
3. Examine the locomotive wiring and
locate each wire and where each wire is
connected; identify the power pickups
for the left and right rails and the
positive (+) and negative (−) motor
connections.
Note: The positive motor connection is
connected to the right rail (engineer
side) power pickup.
Figure 4: Conventional DC Power Pickups
4. Disconnect all wires that lead to motor
terminals.
Note: Some motor connections are
made by a spring contacting the “live”
chassis. In this instance, remove or
modify the spring contact. Be aware that
the motor and frame are permitted to
make contact when the body is
reinstalled in some locomotives.
5. Set the multimeter to continuity or
ohmmeter, and touch both meter probes
together. Ensure it reads 0 (short circuit)
to verify the meter is functioning
correctly.
6. Touch one probe to a motor terminal.
7. Touch the other probe to the
locomotive’s frame, then to the power
pickup wire for the left rail, then to the
power pickup wire for the right rail and
ensure the meter indicates an open
circuit.
8. To complete the test, remove the probe
from the terminal that has already been
tested and touch it to the other motor
terminal. Then, ensure the meter
indicates an open circuit by performing
the same test with the other probe:
touch it to the frame, the left rail pickup,
and then the right rail pickup.
9. Disconnect all lighting wires.
10. Using the ohmmeter (or continuity
tester), verify each lamp lead is isolated
from the locomotive’s frame, the left rail
pickup, and the right rail pickup.