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USA Trains SD40-2 LM-4S-G installation

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Gino:
Has anyone installed an LM-3S-G or LM-4S-G in an USA Trains SD40-2?
I loaded the new software per the instructions and tried to set the Full Load Current. The locomotive tries to set the current per the test but the current draw appears to be more than the PWR-56 can supply and sees the load as a short and shuts down. The test times out so the Full Load Current never gets set.
Has anyone come across this problem? If so is there a solution?
I have not seen this problem with other USA Trains 4 axle locomotives.

gregeusa:
The gearing is a bit different, and a little more friction driving the 3rd axle.

I'd try measuring the amps it draws on DC and see if something is abnormal.

even though the PWR56 is 4 amps, it is only 14.2 volts, really not appropriate for G scale, most G scale needs at least 18 volts, many G scale is 24v on the rails.

USAT motors have a very high stall current... for years the only decoder people would guarantee on USAT locos was the 8 amp NCE decoder.

So, see what it pulls on 14.2 volts... a cheap Harbor Freight meter will do the job.

Greg

Gino:
I measured the current draw using a Chicago Model International 40MS DC power pack.
At full speed with the locomotive on the track and the wheels spinning the current draw was approximately 3.6 amps in one direction and approximately 3.2 amps in the other direction.
Track voltage is approximately 14.8V.
This is an older locomotive I purchased used so I am not sure the conditions of the motors. If there is info on what the typical current draw should be that would be nice to find out.

Appreciating the response.

gregeusa:
So you are very close to the rated current for the PWR56, and note that your meter is undoubtedly averaging the reading, so peaks could easily exceed the 4 amp rating of the PWR56.

I would suggest trying a higher current supply, but then of course you are also reaching the limit of the decoder itself.

Greg

Gino:
Greg,
Thanks for responding.

The PWR-56 comes with a PA-2 Brick power supply
So if I am clear on what you are saying you could replace the PA-2 with a Brick power supply with a higher current rating.
This would make sense but will this be a problem for the PWR-56?

Another option, since G Scale uses a higher voltage, would be using a Brick or filtered power supply with a higher voltage, say 18 volts and higher current rating. Again would this be a problem exceeding the input requirements for the PWR-56?

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