Converting Lgb 23881 back to DC

Greg Elmassian

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I read it as he melted the pins in the header soldering the jumpers.

Agree with what you said, although will caution to use some OTHER socket to keep the pins from shifting when making the jumper, NOT the socket on the decoder.

Greg
 

Tumble99

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Hey all, I am using the rcs titan trackside with out a pwm to linear converter, I’ll be ordering one shortly.

Bellow are the attached links for the power supply and track side titan. As described by others the rcs titan is similar to an aristocraft engineer, it is remote control dc power.

The power supply I am using is a laboratory power supply which goes up to 24 volts and 6 amps. The locomotive, draws two amps at 24 volts.

There is no argument from me about the locomotive will run slower with a decoder, however the loco runs at a crawl regardless. I don’t expect, nor want the loco to run as fast as an Lgb stainz, a light gallop would be nice.

With out a doubt it is very interesting the lack of available available on the 23881 vs the older uintah mallets.




 

Tumble99

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2 amps is too high for that loco... to check, is that current draw unloaded (no train), or on rollers?

2 amps at 24 volts is almost 50 watts !!!!

Greg
Comfortably less then 2 amps the transformers ampere reader is not linear, I will have to find my ampere meter, I haven’t had a proper need for it recently.
 

Software Tools

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In a conversation in another place, Eddie posted a picture of the loco running on a rolling road with about 22V DC voltage. It was running slowly (for that voltage) and it looked to me that the two drives were running with a noticeable speed differential, which was greater than I would expect to be the case in prefect world rolling road conditions.

I'm wondering whether the slow running may due to mechanical issues in the motor blocks rather than in the Massoth decoder settings. The high-ish current being drawn would also suggest that there may be issues in the motor blocks.
 

Tumble99

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In a conversation in another place, Eddie posted a picture of the loco running on a rolling road with about 22V DC voltage. It was running slowly (for that voltage) and it looked to me that the two drives were running with a noticeable speed differential, which was greater than I would expect to be the case in prefect world rolling road conditions.

I'm wondering whether the slow running may due to mechanical issues in the motor blocks rather than in the Massoth decoder settings. The high-ish current being drawn would also suggest that there may be issues in the motor blocks.

I don’t agree, only because when direct power is put to the motors. Mechanically the valve gear and motion goes as quickly as you would expect for the voltage.
 

Greg Elmassian

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I gather this is a video, not a "picture"? Link please?

If I read your sentence properly (it's actually in 2 sentences, the first incomplete), applying power to the motors directly there is no issue.

But you posted using the shorting plug did not make it much faster.

If all of this is true, then the only issue would be the power pickup from the wheels, through the pickup "brushes" and to the main board.

You could debug this pretty easily by leaving the plug in and applying DC power to the decoder directly (top of the pins of the shorting plug) bypassing the wheels and entire power pickup system.

Something is definitely fishy in the loco or part of the data reported is not correct.

Greg
 

PhilP

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OP is also feeding the track with PWM power from the trackside unit. - Says he will get a filter..

PWM could well be confusing the decoder, but the motors direct would not care..

There could be a problem, in one or more of the motor blocks.. This could be a sick motor, or could be a mechanical issue?

If the lab psu is variable, it could be used to directly drive the loco. - It may run fine, with pure dc into the decoder?

There may also be pickup issues, as alluded to by Greg.
I think we still need to break the problem down a little?

PhilP
 

muns

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Well on a moderators note, I'm glad the bickering has subsided because I get angry when there is bickering...and you don't want an angry mod, things happen without warning! There are some lovely buttons that are available to me, some of which I'm itching to try (ban) so please play nice.
 
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Tumble99

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Had a bit more time to work on the loco today , cleaning the pickups and wheels etc

After which I test ran the locomotive with a make shift rolling road (set the drivers in the air and in fact too embarrassing to show here ). I Found that the loco would run fine but perhaps a little slow up to 17volts and around an amp according to the transformer. However if the voltage was increased the amps to balloon approximately to 2 amps and the locomotive would then stop, and run intermittently until the voltage was reduced.

Furthermore at end of the run I noticed the front motor was running hot at the end although that was the block that was powered.

The plan for tomorrow after work is to test again with the back block being powered to see if it is the same, if not faulty motor is a potential cause.

Once again thank you to all, i don’t have much experience with locos past 2002 really and dcc is really beyond my scope. Sorry for causing such debate over what Lgb used during the made in China era.
 

Greg Elmassian

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To Mike, yes we finally got to what was going on. Persistence and pictures to prove what was what eliminated arguing.

Tumbel, good on you for making a makeshift rolling road, EXCELLENT! Never embarassing to show ingenuity or resourcefulness!

So, it seems that you are narrowing it down to one motor block.

It really sounds like mechanical (excessive friction somewhere) or the motor is bad. Motors can fail in interesting ways. It could be something as simple as brushes so worn that they act erratically, or shorted windings in the motor, which can act up when they get hot. (the insulation on the motor windings (wire) is very thin, so you can have damaged insulation that show up as a partial short when the windings heat, they are copper, they expand and can touch each other through damaged insulation.

The insulation on motor windings is a very thin coat of enamel paint, effectively. The motor current really seems to point to damaged motors, but it could be drivetrain binding, although binding usually is erratic, and comes and goes with each revolution.

Keep at it, you are progressing!

Greg