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I attempted to run a PS2 MTH MU set after a couple of years of storage. The engine came up on the remote, but at 2 SMPH the unit was off to the races. I stopped the engine and did a factory reset. The process deleted the engine, but when I attempted to "add" the remote read "Engine not found". There was some intermittent crackling sounds from the speaker. I noticed there was a 7-8 amp draw. I shut down the power and as I approached the engine I could smell that acrid burnt PCB odor. I took the shell off and immediately noticed the NiCd battery appeared to have a brown sugar type substance on and around the holder. The substance was not near the circuit boards. Inspecting the boards, there doesn't seem to be anything swollen or burnt.

1. Could the failure be caused due to a damaged battery?

2. Could a failure with the circuitry have cause the battery to rupture?

3. Would it be safe to swap out the battery, or would there be potential to ruin the good battery?

4. The IC's look modular. Could this be an under $100 repair?

As many can probably relate, the days of a $200 repair are over, being on retirement! If this problem sounds expensive, is there an inexpensive motor driver board, and if so, what would you suggest. Gutting and downgrading may be my only option.

Rich 

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Last edited by Smoke Stack Lightnin
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If this just happened, the odor from any burnt material should still be lingering.  You should be able to sniff the boards to localize the source.  Once you determine it is on a particular section/side of a board, look really carefully and I'm thinking you'll see a bulging component or darkened spot on the green colored board.  If you're going to rip out and junk the board set anyway, perhaps it's worth rolling the dice and trying a DIY repair.  

The item is 20-5676. The pronounced smell is gone, it just has the normal electronic smell when holding it close. I didn't see any darkened areas or bulging components. I guess a hemorrhaged battery would not cause runaway on start or 8 amp draw? The engine would stop if I reduced speed to zero, but would take off at one smph. Maybe I cut the power in time not to cause a total fry? I didn't have the Z4K over 13 volts.

Looks to me like a 3 volt board....Can you address the engine in command?   Take a look at the motor wires right on the motor. Make sure that  no frayed wires are touching the motor casing...That will cause a take off and also look at  the spacing been  the  track reader   and timing tape, should be about the thickness of a "dime"

Are you running it with the leaking battery?  If you can command the engine via DCS, then the engine is being "found" by DCS and I too am hopeful you can slide in under $100.  In any event it's obvious you need to replace the battery (under $10).

It's smart to keep the Z4000 voltage as low as possible in this troubleshooting phase.  DCS operates just fine at 12V. 

Are you seeing 7-8 AMPS on the Z4000 when you command the engine to 1-2 sMPH with "only" 12V?  Or are you seeing 7-8 AMPs when the engine starts up and is just sitting there at 0 sMPH?

Note that you can run the engine in command mode with the battery disconnected.  If this causes the 7-8 AMPS to disappear then that's a good clue.

BTW, you said a MU configuration.  I assume you're just running the engine in question without its companion.

 

Last edited by stan2004

It doesn't look like the battery is bad. Check it with a voltmeter.

It looks like a capacitor near the battery has serious problems. check parts near the battery. Do not assume the factory put the capacitor in the right polarity. Capacitors with reversed polarity used in low stress applications can last a while before failure.

I "make" the 5V connector boards.  I just take an old 5V board and pull the connector plastic bodies off, pull the 3V ones off the replacement board, and slide them on.  A little heat helps soften the plastic and make them come off easier.  The emphasis is on "a little heat", just enough to make the plastic more pliable.

It's sometimes possible to repair the boards, depending on what is wrong with it.  What exactly is the fault?

gunrunnerjohn posted:

I "make" the 5V connector boards.  I just take an old 5V board and pull the connector plastic bodies off, pull the 3V ones off the replacement board, and slide them on.  A little heat helps soften the plastic and make them come off easier.  The emphasis is on "a little heat", just enough to make the plastic more pliable.

It's sometimes possible to repair the boards, depending on what is wrong with it.  What exactly is the fault?

Exact problem: unknown. Symptoms: unable to charge battery PROPERLY while running.

I will send you an email as not to hijack this thread. Look for it in the coming days.

Last edited by Santa Fe 3751

Thanks for your help guys, I know it is hard to diagnose without having the item in hand. To answer a few questions:

The engine is a stand alone (interurban set).

The high amp draw happened while engine was idle with track power applied (cracklings from speaker).

While the engine was moving, it was taking 3 amps at 13 volts. Note the engine and 3 passenger cars have strip lighting.

The battery pack is distant from the PCB's. The speaker enclosure is in between. The brownish discharge is limited to the battery, battery holder, and wires leading from it.

I'm thinking about borrowing a battery from another engine, keeping the Z4k at 12V, then watch (and smell) what happens. I'm thinking it was power board suicide, so I might be shooting you an email John.

Thanks again everyone for being there!

Rich

The PS-2 3V board both processor and power supply can be repaired and this will be under $100.   I have never seen  that happen to the battery.  My recommendation is to remove the 7 pin connector and power engine up.  If still a short, you have an AC problem so check the center rail pickup.

If short is gone, the board is the issue.  I would remove battery and power up slowly.  If you see amps going up above .7 amps, shut power off.  Board needs to be tested.

Continued powering up of a damaged board can causes issues.  I also would not add another power supply unless you shut it off immediately if amps above .7amps.  There are processor faults that will damaged Power Supply.  G

Santa Fe 3751 posted:
gunrunnerjohn posted:

If it's just the power board, those can be had, I have several in stock.

Would you have the power boards with the 5v (black) quick connectors as I have a good processor but bad power from a 5v to 3v upgrade.

You need to be careful just swapping, see my notes above.  Processor faults can damage power supply.  If processor is good, Power Supply can be repaired.

Also PS-2 3V boards are still available, though in limited quantity.  G

I power them up on my bench and use my #91 magnetic breaker set to it's lowest setting for testing.  It will trip instantly on a bit more than 1 amp, and is useful for testing suspect boards.

I also have an ammeter connected so I can monitor the power as I bring up the voltage.  If the current just ramps up as the voltage comes up, I presume that there's a problem with the board and stop.  I agree that it's easy smoke things if you're not careful.

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So it drops from 7-8 Amps when stopped to "only" 3 Amps when moving.  That's interesting.  This suggests to me an issue in the motor drive electronics.  Can you pull the 5-pin connector on the bigger (processor) board that goes to the motor?  It usually will have yellow and white wires.  Obviously the engine will not move when commanded but does this change the 7-8 Amps? 

Likewise, you can pull all the harnesses from the boards and add them back one at a time if you're up for some DIY troubleshooting.  Obviously you must have the 7-pin power connector plugged in for anything to happen at all.  You should hear the relay click when power is initially applied.  Check the Amp draw.  Then start again with the battery connected.  Check the Amp draw.  Etc.

Note that if the engine is drawing 7-8 Amps at 12V-13V that's a whopping 100 Watts or so of power.  When idle, an engine should be drawing something closer to 5-10 Watts. That extra 90-95 Watts of power is going somewhere!  In other words something is heating up very quickly in your engine.  Think of touching a 100 Watt incandescent bulb when you turn it on...it's a matter of seconds before it's too hot to touch!  Now imagine that power concentrated in a tiny electronic component.    Point being the smell is a result of overheating so even if you shut down the power, the heated component(s) will take a while to cool down and you can localize the source of the fault by looking for the heat source.  Poking around with "fat fingers" to find a burning component is problematic, so you can take a Q-tip with 91% rubbing alcohol and dab around.  A hot component will evaporate the alcohol instantly.  Obviously some experimentation is required to get a sense for evaporation rates.  Just a thought.

No offense Stan, but I think in this case, he's better off having someone look at the boards.  I agree with George that pulling the 7-pin connector and testing for a short makes sense.  If it's the boards, there's very little that a novice is going to fix on those.  If it's drawing amps of current before it's added to the remote just by powering up, there's very little chance that it's anything but the boards.

Agreed.  But it seems to me that to meet the $100 threshold, it has to be a DIY component-level repair.  He's already in for $10 or so to replace the battery.  To swap the power supply board would be at least $80 and apparently it's only available to Authorized Service Centers.  Don't know if ASCs mark up parts like my auto repair shop.  Then there's the labor cost and I assume they charge more than minimum wage.  Add 2-way shipping charges - since engine takes off full bore at any commanded speed there could be a tach issue which might require sending in the entire engine which further jacks up shipping/handling.  And so on.

ps2 board replacement cost

Hence I figure Rich needs to perform some level of DIY troubleshooting.  My scenario is one of getting "lucky" where replacing a $2 component does the trick.  Maybe a buddy can do the soldering if that's not his thing.  I'm not saying it's likely but if you were in the path of the total solar eclipse (like I was) last week, you come to appreciate that miracles do occur.

 

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Lots of good advice here. I will try some of your suggestions to see if I can narrow down the possibilities. I will respond to this thread with my findings. If it looks like the repair cost is out of reach, maybe someone could suggest a basic motor/directional board as an alternative? I think Williams-Bauchman sells one. I do have basic soldering skills.

Rich

$5 to ship board to me and test and repair after estimate.  Swapping power supplies and smoking another $80 board with 2 engines that now do not work is priceless.  Once board test and repaired, it is simpler to point towards a review of the wiring which can be done now while boards removed.

Keep powering a board that is drawing more than .7amps with no load is $0, but if the short permanently damages the board, it is another $200.  Which is not quite priceless.  If it happens to be a flash board, then it will be a PS-32 upgrade, which also is not quite priceless but close.  No more flash board in stock, so engine requiring special code have to be repaired with the PS-32 board now. G 

I finally got around to doing the procedure GGG suggested on 9/4/17, 8:07am. I disconnected the 7 pin and at 12V it drew .7 amps exactly. I reconnected the 7 pin and powered up with 12V. The amp draw fluctuated between .2 and .3. The board didn't heat up during either procedure. With the 7 pin connected there is a buzzing noise almost like a sticking relay sound. If I press down on the heat sink(?) (I'm referring to the black rectangular that is connected to a metal frame) it will stop, but if I nudge the assembly it comes back. The board is fastened down not to tight, not to loose. I do not have a battery connected. The engine won't load into the remote. I tried to add it numerous times, with the buzzing and without, always getting the "no engine to add" error.

Does the battery need to be connected to add an engine? As I said, the battery for this engine leaked a brown sugary looking substance. I can remove a battery from another engine to further test if one is required to add an engine. If a battery is not required I'm at a loss at this point.

Does this shed new light on the problem?

Rich

 

GGG is right - check the AC power for a short.  Remove the 7-pin connector.

Apply power SLOWLY and note at what voltage the short occurs.  You should be able to apply all 22 VAC without a short.  If the short occurs, the problem is on the bottom of the power truck, where the center rail connector is in very close proximity to the outer rail connector. The problem is in the connector on the wires.  There is a very small tab on the outer edge of the connector, the opposite end of where the wire connects.  This occurred during manufacture.  The vendor did not remove the tab prior to installation.  I learned this from Jon, in the Service area at MTH during classes this summer.  The solution is to remove the outer rail connector and attach it to one of the screws on the truck frame.

Unfortunately this occurs on early PS2 3 V locomotives.  To protect yourself - always power up the locomotive SLOWLY and if a short occurs, problem solve before damage to the boards occurs.

bruce

Independent MTH ASC Technician

 

 Just a note, I have seen this condition with this battery. The engine still ran but started having issues with memory of settings. When I checked the battery from the inside of the shell, I saw the same thing. If I remember correctly again, the voltage was low (1.8v?) when checked with a meter and no load.

 I would also comment that the Z4000 should have a inline fuse attached for this situation. It will probably fry everything before it reacts IMO.

The Lionel 180w brick will trip fast and I still have fuses on them. I change the fuse to a small one when working on a problem engine. You can't react fast enough...... unless you can above the speed of light!

I can't see the good of applying power over and over to an engine with a known issue like this. A probable under $100 repair will be a long shot the more damage that is done.

 Users that have become educated on fixing trains all start somewhere. I just think talking it over rather than applying power and posting the results would be in order here.

Last edited by Engineer-Joe

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