Large Scale Central

Revo compatibility question w/ USA trains

Electronics Power and Sound
#1

The topic is odd but i’m having a problem and i need the collective groups mind. scary.

So I put a Revo in a boxcar with a LiIon 14.8 6600 battery. I am only using the motor leads to power locos.

I am using a USA trains NW-2. I have disconnected the track pickup plugs and put a lead on one. The lead goes to the boccar. All seems normal. Here’s the catch; when the revo powers the loco the lights don’t work. Before you ask, yes the light switch is on. BUT, when I power the loco through the same jack but with a cheap LGB power pack the lights work fine. I have changed the polarity of the battery jack, the motor jack, I have connected to the other track pickup. I have matched the polarity and voltage of the powerpack. All to no avail.

Any thoughts? Cause I’m lost.

Thanks for any help,

Terry

#2

Terry,

Aristocraft’s Revo outputs digital PWM (pulse width modulation) verses straight analog DC.

Michael

#3

So direct wire lights to motor leads instead of relying on the USA electronics?

#4

Hi Terry, there are two styles of lights for the NW-2. Old style uses 18 volt bulbs and can be wired directly to the motor leads. But the newer version uses 5 volts and you need the engines circuit board for the 5v lights or you will blow the lights. However, you should use the circuit board to provide bi-directional lights. What version do you have?

On the NW-2 there are two lighting jacks below the rear door. These can be used to power the loco and lights. Just unplug the four wires from the wheel pick ups.

Let me know. Don

#5

I spoke with the gentleman I’m doing this for. He opted to put the revo in the loco. So, as Bart would say, out came the screwdriver of destiny and the +5 wire cutters of removal. Problem solved.

T

#6

Here ya go Terry;

http://ovgrs.org/the-trains/battery-power-radio-control-and-sound/usa-trains-nw-2/

Paul N. with the OttawaValleGRS has written-up a whole bunch of fantastic (imho) how-to articles, lo and behold even one regards NW-2, and possibly the config’ you were in the mid’ of attempting !!

doug c

#7

Terry much better install onboard. Here are some suggestion if you are not aware of. I just cut off the track pickup wires that are attached to the side frames. Then unplug the other two inside red/black wires from the motor block. Pull that harness inside. Next inside the loco unplug the two sets of motors wires. I reuse the 4 wire plugs to reconnect the motors wires together. Next you can use the extra black red wires to connect to the REVO motor output. Or cut off the plugs and solder all the wires together.

If the lights are 18v connect them to the REVO. If 5v I use my relay-U board to interface to the USAT board forbidirectional constant lighting. However, the REVO shuts off the lights when you stop.

Don

#8

Thanks Doug. I should have thought to look there. It pretty much summed up what I thought, after Michael telling me it was PWM of course. Don, thanks. It has the 5v system but i’ll just put LEDs in it.

Terry

#9

Thanks Doug. I should have thought to look there. It pretty much summed up what I thought, after Michael telling me it was PWM of course. Don, thanks. It has the 5v system but i’ll just put LEDs in it.

Terry

#10

Don mentioned about using the redundant track power wires from the motor blocks as a wiring harness to connect both motors to a radio control receiver. It’s a pretty slick trick he showed me to wire an F-3A.

These connectors have four wires each. Take a red wire from each of the connectors and solder them together. Take a black wire from each of the connectors and solder them together. That joins the two motor connectors together as shown at the top of the T.

Twin Motors Wiring Harness

The remaining red and black wires of one of the connectors are used to connect to the receiver’s motor output terminals as shown on the right. I soldered a 2-wire connector set to them because the receiver was mounted in the top of the hood, and I wanted a way to separate the shell from the frame.

The remaining red and black wires of the other connector were soldered to a 2-wire connector as shown on the left to be used as an MU plug to power a trailing F-3B unit.

#11

Don also mentioned a Lights Relay Board.

This allows a redundant track power connector on the USA Trains main circuit board to be connected to accessory battery terminals on the receiver. This provides clean linear DC power (not PWC) to allow the USA Trains 5-volt regulator to function properly and power the lights at full brightness. The relay provides directional lighting.

Lights Relay Board

#12

I’d think on battery operation, it would be best to replace the incandescent lights and the inefficient linear regulators with LEDs.

Less wire and cost also.

Greg

#13

Hi Greg, technically you are correct. But for those who do not want to rewire 3-9 lights on a given loco this is a simple non-invasive way to keep the lights working. The relay is $32 compared to $6.75 -$20.25 for new leds and hours of work.

Battery power on a USAT loco using it lights can last on average 2-3 hours using our 14.8v 2200 lithium pack.

I tried running my USAT streamlined cars standard lights on a battery but that was short lived. Those cars can draw 2 amps sitting still! Imagine replacing all those bulbs.

Don

#14

Depends on the loco for me. For “old” steamers i use incandescent lamps because no matter how you slice it LEDs do not look like old lamps. For modern locos I tend to install bright white LEDs and for old diesels I use warm white. BUT this is my taste. If i’m doing installs I put what the owner wants in them.

Switching LEDs is quick and easy. I can do a USA GP unit in about 2 hours for under $10. That’s 4 headlights, 4 number boards and 4 directional lights. Most i’ve done don’t want the cab light. But, I see the merit for those who wouldn’t want to do the work.

T

#15

While working on the F-3A F-3B project I looked for easier ways of installing battery power, radio control and sound. I have no trouble making my own LED circuit boards, and usually do for USAT diesels. But I am aware that many large scale owners are solder-phobic and electronically challenged, present company excluded. The Relay Board made it much easier to understand and install.

I am sure if I added this diagram for the USAT Christmas tree marker lights, a lot people would have a better chance of winning Clash of Clans that understanding how this works.

USAT Marker Lights

#16

Paul, for the USA trains locos with the directional lights I change them to a two pin multi polarity green/red 3mm LED. I then wire them to the motor lead.

I’ll keep the above in mind though. A couple diodes and a resistor seem to be just as simple. Thanks for all the help, i keep printing all these and adding them to my files.

And for the record, my clan is up to level 7 and we haven’t lost a war in six months. :slight_smile:

T

#17

Not really solder phobic, Paul. Some of us, like Clint Eastwood said " A mans just got to know his limitations" and to me the thought of taking a brand new loco I just got and doing open hood surgery on my own with not a real clue of the step by step involved to convert my -38 to battery makes the paying someone else to do it much easier. Maybe after I get one done, I can use it for reference and do the rest by myself, but would hate to turn that brand new , and only, loco into an expensive paperweight/display model. I hope i can take some of the knowledge on LSC and one day actually apply it , once I get a feel for how things work.

#18

Pete, As long as the motors (trucks) still work, it should not actually become a paperweight. In fact some folks gut all the wiz bangs out of their locos and start with a blank slate. But it is daunting to start surgery on your new “baby”.

#19

I like the unknown and have taken locos I have never seen and rewire them for DCC, track power or battery for others.

After troubleshooting mainframe computers for 45 years, the engines are very simple to me.

#20

Dan, but that is where some folks have an advantage over others. We understand wiring diagrams and we can figure out what is going on inside of the loco rather easily. To other folks, its just PFM.