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MSR17

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Discussion starter · #1 · (Edited)
First off, a sincere “Thank You” to those who responded to my initial query about my “Dead As A Doornail” LGB 21261 locomotive.

I’ve been able to hardwire the motor and, thankfully, it functions well.

I’ve isolated the problem, the engine isn’t getting track power.

What I believe:
the slide shoe pickups are used to power the lights & smoke unit. Electrical continuity is established by two inner vertical metal rods which contact the shoes and pass the current up to a four slot female electrical plug via the rods protruding thru the top of the Motor Brick.

Given:
The drive wheels have six spring-loaded, electrically isolated wipers to pickup current from the six drivers. One for each rail. To provide continuity across each driver set, there is a wiper across the three axles.

My question?

I would think that the two outer rods which also extend through the Brick to connect to the two outer plugs in the four-slot female connector would have to establish continuity somehow to the driver wipers and/or the slide shoes…
But they don’t. They don’t seem to touch anything regarding the pickup mechanism. And these two outer rods power the motor.

Does anyone know how continuity is established between the outer rods and pickup mechanism? The PDF’s are unclear.

Learning slowly but surely.Thank you again for your help.

Mitch
 
#2 ·
Download the 20261 manual to see all the parts plus the electrical cabling diagram. When removing the bottom motor block plastic plate one must be sure to place the 2 long silver bars to contact the middle 2 pins (track power) and the outer pins are just motor connectors to the 4 pin cable on top of the motor block.
 
Discussion starter · #3 · (Edited)
piercedandan said:
Download the 20261 manual to see all the parts plus the electrical cabling diagram. When removing the bottom motor block plastic plate one must be sure to place the 2 long silver bars to contact the middle 2 pins (track power) and the outer pins are just motor connectors to the 4 pin cable on top of the motor block.
Click to expand...
Thank you for responding, appreciated!
Regarding the outer pins, shouldn’t they connect to current as when I apply current to the outter pins, the motor functions?

I confess, I’m unsure of the purpose of tha electronic board. Perhaps it’s suppose to supply current to the motor???
Image
Image

Been studying the explosions, but I can’t quite cipher if/where those pins connect to anything.
 
#4 ·
Here's my take:
Item 69 connects the three wheel pickups and the shoe pickup
Pins 68 connect from 69 (one left, one right) up and out the top of the motor block (Item 65).
Pins 67 connect from motor pins, up and out top of motor block.
So pins 68 (power pickups) and 67 (motor) extend out the top of the motor block forming a 4-pin male connect.
NOTE: its hard to tell but 67 (outer pins) may be motor or pickup with 68 the other. An ohmmeter would confirm.
 
#5 ·
One more thing, the interconnection of all these pins, wipers, etc. rely on contact under pressure.
In this case the motor block assembly must be fully assembled and all screws snugged down.
Also, if it has been over-lubed with oil etc, the oil may have worked into the contact areas and is isolating the connection.
A disassembly and cleaning with alcohol for Items 67,68,69, motor pins may be in order.

An ohmmeter on the two outer pins should measure resistance on the motor (less than 20 ohms?)
An ohmmeter for the left inner pin should have 0 ohms to the left wheels and pickup shoe. Same for right.
 
Discussion starter · #6 ·
wraujr said:
Here's my take:
Item 69 connects the three wheel pickups and the shoe pickup
Pins 68 connect from 69 (one left, one right) up and out the top of the motor block (Item 65).
Pins 67 connect from motor pins, up and out top of motor block.
So pins 68 (power pickups) and 67 (motor) extend out the top of the motor block forming a 4-pin male connect.
NOTE: its hard to tell but 67 (outer pins) may be motor or pickup with 68 the other. An ohmmeter would confirm.
Click to expand...
Thank you!
I’m unsure of the purpose of the electronic board, but…Im beginning to think outer pins
Supply current from the board TO the motor.

Do you, perhaps, know the function of the Board?

Thanks again 🤗🤗🤗
 
#7 ·
The board is supplying distribution of power to all the various functions (i.e. motor, smoke, headlights, cab light, lantern lights.)
The is why all the various cables come to the "board"
So the two inner pins on the motor block are from the track pickups (wheels and shoes) and this supplies track power to the "board".
From there the power (lets call it voltage) is distributed to all functions including motor.
Depending on smoke unit and headlights (LED) there may be electronic circuitry to generate the proper voltages (from the track voltage) that is required.
There is also a switch on this board that controls whether lights/motor/some combo are powered. See owner's manual
 
Discussion starter · #8 ·
wraujr said:
The board is supplying distribution of power to all the various functions (i.e. motor, smoke, headlights, cab light, lantern lights.)
The is why all the various cables come to the "board"
So the two inner pins on the motor block are from the track pickups (wheels and shoes) and this supplies track power to the "board".
From there the power (lets call it voltage) is distributed to all functions including motor.
Depending on smoke unit and headlights (LED) there may be electronic circuitry to generate the proper voltages (from the track voltage) that is required.
There is also a switch on this board that controls whether lights/motor/some combo are powered. See owner's manual
Click to expand...
Thank you!
So the outer two pins supply voltage to the motor?
I think what confused me are the various electronic devices (capacitors, dip switches etc). But I recall this board is DCC-Enabled (via the six-prong white male connector on the upper right.

So I’m assuming the electronic components are for interfacing with the DCC board & have nothing to do with their tor, lights & smoke unit?

Thank you for you explanation! 🤗🤗🤗

And I’ve made sure the Cab’s Selector Switch is set to “2 / Fully Operational”
Image
Image
n
 
#9 ·
You said: "So I’m assuming the electronic components are for interfacing with the DCC board & have nothing to do with their tor, lights & smoke unit? "

No you can't assume that.
I am no LGB expert, but I have heard that some smoke units require a different/controlled voltage than the track voltage. So some of that circuitry
could be a power supply for the smoke unit.
If lights are LEDs they can't be connected directly to track power and need a few components to properly regulate the voltage to the LED.
And then there may be circuitry for supporting DCC.
Can't really know for sure unless you have a schematic diagram for the board.
 
#10 ·
The upper right 6 pin socket is for a cable (55026) when using the LGB DCC decoder. The 4 switches on the left are for disconnecting track power from the motor when upgrading to DCC as the motor has to be completely isolated from the track power.
 
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piercedandan
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