LGB 21382 Streetcar - excessive current drawn..

The 3 way connectors are the reed switches & "clock" for the sound unit.
 
dutchelm said:
The 3 way connectors are the reed switches & "clock" for the sound unit.
Doh!
I completely missed the pickup/motor connector at the other end of the block!! :o ;) >:(
 
Sorted!! ;D ;D ;D

Thanks for all the input, guys..
Continuity of pickup all the way down each side, and draws just over an Amp almost constantly.
now, just 'google' a picture to 100% check which way round the vents go back on, and Robert is your mothers brother!!
;) :D
 
I may have spoken too soon..

The loco will run quite briskly, analogue 15V at 1Amp, but there is a 'warm' smell after a few minutes..
Not sure if there is oil being burnt off, or it is just me being hyper-sensitive?? That does represent 15W being dissipated somewhere, so there will be some heat..

On DCC, the lights seem to be overly dim, but the unit will run quite happily for over 20 minutes..

I am a little concerned it is still drawing too much current.. Solving the pickup problem has helped, but I now wonder if the decoder has been 'cooked' as well??
 
I have put my tram on the rollers. Lights & sound on. Using a stabilised supply at 15 volts it was taking about 0.75A. Doesn't sound good for yours.
 
Thanks Mike.

I did wonder if it was just 'tight'.. It is 2003 vintage, and does not appear to have had much use.
I have had it running for about 30 minutes. It smells a little warm, which I feel is not good.

Think I will have to strip it down to the decoder to see if it shows signs of running hot.. :(
 
Phil
Before you disassemble again it may be worth removing the bottoms of the bogies (sorry trucks) to see if the grease has not solidfied & is making things stiff.
 
Mike,
I have had the motor-blocks apart, to sort the pickup problem..
Initially, I thought it might be oil contamination of the motors (still might be some of the problem), as there always seems to be quite a bit of 'oil' around the joining faces of motor-blocks. - ?Does the grease break down, releasing 'oil' and drying out?
Thought it might be a film of oil acting as an insulator on the wire/rod linking brushes and skates, but this was not so.
Lubrication seems fine.. Motors (on their own) take about 0.3Amps each (at 15V analogue), which would mean 400mA for sound and lights.. Lights appear dim, though sound is fine.
If I run it at 15V and it is drawing 1Amp, it will occasionally 'twitch' and take a larger current for an instant. - Whether this is just down to dirty wheels etc. or 'something' within the decoder I do not know.
 
Earlier this year a mate acquired a shelf queen test run only New York version for a good price.
It suffered from poor pickup so the bogies (trucks) needed attention. I wasn't 100% happy with the motors so I stripped them down for cleaning. Unlike most motors I've had to strip down there was no sign of internal lubricant contamination but, in view of its lack of use, a surprising amount of carbon dust inside the motor casing. The commutator was pristine, confirming the lack of use but the slots were partially clogged with carbon dust. Current draw was reduced by cleaning these out. I wondered if they had a bad/different spec. batch of brushes with these motors. I advised my mate to keep an eye on the current in future especially as I burnt out his decoder in his other, New Orleans, version when checking the pickups.
If it turns out to be the decoder and you need a factory replacement one German source is in this link.
http://www.modell-land-service.de/014100-onboard-decoder-69800s103-p-9447.html
 
Thanks Neil..
I have followed other threads about stripping down Buhler motors. - They have either a red. or buff/brown plastic end I believe.. as this is a 'Chinese', supposedly, vintage item, will it have buhler motors do you think?
 
PhilP said:
Thanks Neil..
I have followed other threads about stripping down Buhler motors. - They have either a red. or buff/brown plastic end I believe.. as this is a 'Chinese', supposedly, vintage item, will it have buhler motors do you think?
The four(two trams) I've seen looked identical to the later "can" LGB Buhler motors. I'd didn't check to see what (if any) markings they had.
 
I've got one of these streetcar's and have had two decoder's blown resulting in the central station tripping out. I did read somewhere that there is a problem with the motor blocks on these. I don't think I will be spending any more money on this unit despite sounding great when going fine, it has cost a fortune to get it repaired only to go faulty a few months later.
 
Kevin said:
I've got one of these streetcar's and have had two decoder's blown resulting in the central station tripping out. I did read somewhere that there is a problem with the motor blocks on these. I don't think I will be spending any more money on this unit despite sounding great when going fine, it has cost a fortune to get it repaired only to go faulty a few months later.
There do seem to be recurring problems with this model..
I *think* the problem stems from the power not being picked-up properly from all the wheels / skates along each side of the unit.. This results in the decoder 'working too hard' to amplify-up the voltage to drive the motors as commanded, and so causes the decoder to overheat and fail.

The 'carboning-up' of the motors does not help with the current-draw either.

As to cost of fixing them:
So far, I have spent a good three hours on this particular unit (some a learning curve, I admit).. This unit is now picking-up properly, and current-drawn is better, but probably still excessive.. It is whether I spend more time on it at the moment (attack the motors, and/or fight my way to the decoder) or send it out 'as-is' and wait for it to fail at some point in the future. - Money spent now, or money spent later!

I suppose cleaning the motors would give them a greater lifespan. This should reduce the load on the decoder, but it could be the damage is already done to this.
<edit>
Motors are around £40 a pop, and looks like a similar amount for a decoder from Germany (in euros anyway)..
 
hmmm... the decoder doesn't "amplify" anything with regard to the motor voltage, it lets (almost) the full track voltage through to the motor and simply controls the "average" power to the motor by varying the pulse width duty cycle (PWM). If the decoder can't draw enough amps from the track via the wheels (due to dirt, dodgy pickups or whatever) then it cannot pass those amps to the motor.

On the other hand if the motor is drawing too much current due to dirt or a bad coil, or there's a short in the block, then that could exceed the rating of the motor control components in the decoder, causing overheating and failure.
 
Thanks Nick.. it was a 'theory'!! ;)

Think I will *have* to have the motors out/apart then.. About 0.3A on a single motor on its' own at 15V analogue is a little excessive.
I might try running the motors (both of them) directly from the regulated supply for 10-15 minutes, and see if they smell 'hot'.. That would show if it is the motors, or the electronics that are cooking..
If the motors do not smell after that, it has to be the electronics.. - That would explain where the extra 0.4Amps is going, though that does not seem too bad for sound and all the lights to me??
 
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