# Adding DCC to Lima F7/F9 with pancake motor (only 1 wire connected to motor)



## ianb26 (Dec 29, 2014)

Hi there,

I just bought a V/Line (Melbourne, Victoria, Australia) Lima F7/F9 which i want to DCC. It has a pancake motor BUT there is only one wire connected to the motor, -on the left hand side - with 2 wires going to headlight bulb, one from the left and one from the white. What would be the track connections. Would the grey & orange wires still go to the motor? Where would the red and black wires on the decoder connect to?

I have attached some photos. The last photo shows the connection from the pickup to the motor. (The one pickup).

I believe it's common that Lima wired their pancakes motors this way. Any help would be appreciated








































Ian.


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## Aard D'Vaark (Aug 1, 2019)

as a guess [remember this is a guess] the grey and orange would go to the motor [where the wires go now], the red and black would go to the wires, and the capacitor between the two terminals on the motor would be removed .. if the unit moves backwards when forward is selected, and the red wire goes to the right wheel, then just reverse the grey and orange wires ..
this can also be done by changing CV29 , but the two wires is [in my opinion] easier to do ...
note: the wire from the motor to the close rear wheel is where the red should go [right side, loco facing away]


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## DonR (Oct 18, 2012)

It is very important that the motor is fully insulated from the loco frame. Some makes connected one brush
to the frame. If this is the way your motor is wired you must break that connection.

The Orange and Gray wires go directly to the motor brushes. No other wires may connect to them.
The Blue wire is Light POSITIVE.
White wire is Front light
Yellow wire is Rear light

The Red wire connects ONLY to the RIGHT wheel power pickups
The Black wire connects ONLY to the LEFT where power pickups

NOTE: You will get much more dependable service if you make
certain that the loco has ALL WHEEL power pickup. You may have
to add that to some older locos.

If the loco backs when controller is set to FW... REVERSE the ORANGE AND GRAY motor connections.

A word of caution regarding the pancake motor.
These usually draw more current than motors
now used. Be sure your decoder can handle at least 2.5 amp draw.

Do an amp draw test. Using a DC power pack or 9 v battery source
set your multimeter to AMPS. Connect negative of source to one brush.
Connect one probe to other brush and the other probe to
the source positive. If power pack raise speed control.
Note Amp draw.

A helpful tip...if the motor does draw too much current and you see
the decoder go pufffttt....you can likely have the decoder replaced
free...I converted a pan cake motor to DCC and that is what
happened...Digitrax replaced it free.

Don


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## ianb26 (Dec 29, 2014)

DonR said:


> The Red wire connects ONLY to the RIGHT wheel power pickups
> The Black wire connects ONLY to the LEFT where power pickups
> 
> NOTE: You will get much more dependable service if you make
> ...


Hi Don,

Nice to hear from you again. I'm OK with colour coding. The thing that has thrown me is there is *only* the solid wire from the left hand terminal to the wheel. Then there are the *2* wires to the headlamp. *No other connection from the front truck wheels to the motor.* 

This can be seen in the last 3 photos. If needed, I can take more photos.

Ian


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## flyboy2610 (Jan 20, 2010)

ianb26 said:


> *No other connection from the front truck wheels to the motor.*


In that case motor is probably in direct contact with the frame, which is acting as an electrical pathway. One set of wheels is providing electrical power to the frame, which is passing it along to the motor. You may need to further dis-assemble the locomotive to find out where that connection is occurring.


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## DonR (Oct 18, 2012)

Ian

It's been quite a while since hearing from you. How are things in Melbourne?

As Flyboy mentions, the frame via one truck may be 'live'. You must disconnect ANY existing
wires to the motor and ensure it's housing is isolated from the frame. Only the Orange and
Gray wires should go to the motor. The lights also may be connected to the frame. They
should also be isolated from it. If ONE truck and frame is 'live' the Black wire would
connect to the frame. The Red wire connects to the 'other' truck's power pickup.
You would want to make sure the couplers are plastic to avoid shorting to a
connected car.

You can test if frame is 'live'. Set meter to ohms...one probe on the wheels
of suspect truck...other probe on the frame. If you get a reading it's live and
you would need to follow above.

Don


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## NSW42220 (23 d ago)

Know this is an old post but just to clarify a few things (I have a few Aussie Lima locos). The frame is plastic so nothing to short out there. Lima's wiring with the motor to the left and viewed from above:
Short wire from the left motor brush connects to motor bogie, its front and rear wheels pickup power from the inner rail.
One long wire from the right motor brush connects to retaining clip on the front (unpowered) bogie, its front and rear wheels pickup power from the outer rail. The same clip retains the bulb but as it only provides outer rail power to it another long wire connects the left motor brush (i.e. inner rail power) to the lamp itself.


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## DonR (Oct 18, 2012)

The wiring of a DC loco is very
simple. If your loco has all wheel
power pickup there should be
a wire from each side of each
truck. Red wire (?) from Right side,
Black from Left. The 2 red wires
connect together. The 2 blacks
also connect together.
Red wire would go to one motor tab.
Black to the other. Other than lights
there should be no other connection
to the motor tabs. (Note previous posts
to get direction of movement correct)
If you are adding Decoder the unit
should provide instructions for the
color coded wires.

Don


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## Lemonhawk (Sep 24, 2013)

Start a new topic, don't resurrect an old one. Inner rail? Is this O gauge or European 3 rail HO? Why are you asking this? Does it not run? Is it DC or AC? Best to just start all over with a new topic and provide more information.


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## NSW42220 (23 d ago)

Lemonhawk said:


> Start a new topic, don't resurrect an old one. Inner rail? Is this O gauge or European 3 rail HO? Why are you asking this? Does it not run? Is it DC or AC? Best to just start all over with a new topic and provide more information.


No prob. Doing my own conversion and came upon this. To quote "The thing that has thrown me is there is *only* the solid wire from the left hand terminal to the wheel. Then there are the *2* wires to the headlamp. *No other connection from the front truck wheels to the motor.* "
Just seemed some confusion about how this particular (DC) loco is wired 'out of the box', before installing a decoder. 

Here one of those wires is the connection from the front truck (pickup is the left rail) to the motor. The other provides right rail power to the globe from the powered truck. If the globe was not removed from the mounting the decoder would probably blow.


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