3rd Rail SP Berkshire EOB problem

Well, I'd start with the normal moves, reseat all the connectors and boards, as well as checking for any loose connections.

 

I'm assuming you're talking about the TAS EOB boards in this engine?

Thanks gunrunnerjohn,

 

According to the instruction booklet, it has the TAS EOB system.

I'll take the tender shell off and see if anything looks as if it's come loose.

Check the sensor eye to sensor tape on the motor maybe make sure there is a 2-3mm gap and not rubbing the flywheel or if the sensor is too far away? Just a thought maybe

Thanks,

I checked that the boards/connectors in the tender were all tight - couldn't find a problem.

I'll remove the locomotive shell and check the sensor eye/clearance.

 

If the sensor doesn't trigger, it takes off like a rocket.

One other thing to check is make sure the valve gear is not bent or binding and the eccentric crank is in the correct position. Sometimes the screw holding it on loosens and allows it to rotate.

OT but does this dealer have any more squirreled away? This ugly duckling is one of my favorite SP engines. I assume it has the whaleback tender?

 

Pete

I checked the sensor tape - it's in good condition.

Sensor space is about 2mm from tape but at an angle - the light blinks each time the black/white stripe passes.

With the engine on rollers, I tried increasing the gap to 3mm and (as gunrunnerjohn predicted) it ran off at full speed for about 1/2 sec and then stopped.

 

Pete,

 

Yes, it has the whaleback tender. I'll ask the dealer if he has any more tucked away.

 

I checked the valve gear and all seems fine.

 

Does anyone know of a source for EOB spares/repairs - I'd prefer not to have to rip out the EOB and install an ERR system!

Well, the three boards are standard Lionel boards, so that shouldn't be an issue, they're readily available.

 

If you're looking for the EOB MB/driver assembly, tell me what exact version you have, pictures would help.  I have several here.

I'd appreciate your checking on availability.

Before replacing hardware you might want to try resetting the board. Its more involved than most TMCC boards.  Thanks to John, I have a pdf I can email you or you might find it here on one of his posts.

 

Pete

Pete,

 

I'll let you know as he gets back to me.

I'd be grateful if you could email me the reset pdf?

 

Gunrunnerjohn, I can't see any version no on the motherboard - can you tell me where I should look and/or which part of the assembly you need pictures of?

Frank

Frank, I didn't see your email but if you check this thread you will find one of John's posts with the pdf you can download.

 

Pete

 

look at my thread..id just picked up a TAS EOB system...got picks of it..see if my EOB board is the same as yours..

https://ogrforum.com/t...87#15649413432618487

We probably should try to narrow down the problem before considering board replacements.  

 

Here's a thread where I posted all the TAS stuff I have: https://ogrforum.com/t...rials-andamp-manuals

 

What you're describing is unusual, but could be explained by an electronic failure, just have to try to narrow it down.

 

The fact that it happens in both directions kinda' makes me think it's not just a bad component, normally that kind of behavior is in one direction.

Thanks,

 

I really appreciate your help on this.

I re-checked the bare board and can see no version no similar to the picture in joseywales' thread.

 

I tried resetting the background pulse etc - no difference.

 

I selected 128 step mode and the locomotive accelerated gently to a much higher speed but, it then stopped responding to TMCC commands - fortunately on rollers not crashing into other trains!

 

Does this narrow things down?

Frank, are you saying your board is different than the one pictured in Joseywales thread? 

The one in the pic is an EOB motherboard. It should match what you see in the EOB installation manual. If it is not the same I suppose you might have an EOB Drop in board which is much smaller.

 

Pete

ok i was wrong i think..look at the instruction manual john posted on my thread..TAS made 2 boards 1 is a SAW the other is a EOB..are you sure you have a EOB board?.Because john posted the manual for saw and thats how id found out i have a EOB system..SAW has 6 wires to the tender=6 pin in the loco..  and EOB has 8 wires...didnt know there was a upgrade cruize kit for the EOB?..Theres 2 versions of the EOB ..your might be the earlyer version and mine might be the newer version..??

https://ogrforum.com/t...r-motor-driver-board

It has an 8 wire tether and the instruction book says EOB.

 

The motherboard looks identical to the one shown in the EOB installation manual and very similar to the picture in the thread - except that there is no "version 2" label on mine.

 

if it looks like the one in the manual..its the same as mine then..didnt you say the tach sencer is on a angle on the motor? if so,try the line it up strait on the motor..on a angle could give the board wrong reading from the motor tach tape..I haven't installed my EOB yet. in my S1 ..just for the heck of it..does your train have the TAS turbo smoke unit in it?

There are actually at least two versions of the EOB board, I have a couple that are the same, and another one that has the connectors in different places.  Yes, they're all really EOB boards.

Joseywales,

Yes - it does have the TAS turbo smoke unit.

I re-aligned the tach sensor - it didn't make any difference.

Gunrunnerjohn,

I'll upload a photograph of the motherboard top after I remove the power, sound and R2LC boards after family breakfast today.

As I test this system, it seems that the EOB has developed some kind of "speed limit" which makes it cut off the motor when the limit is reached/exceeded.

 

Again, thanks for your patience and help on this.

If you still have access to the motor verify the distance from the sensor to the flywheel is .030". Not sure of the exact tolerance but too far or too close can generate pickup errors.

 

Pete

I can't see pickup errors shutting down the board like that, but obviously it doesn't hurt to verify it.

 

I wonder if it's possible a component on the pickup board is failing and causing some odd issue?  I'd think a runaway would be the usual result, that's what always happens to me with pickup errors on these or MTH stuff.

 

I'm thinking maybe bad drivers that overheat whenever you draw too much current?

just a curious question john..what if the tach reader might be going bad? wonder if that can cause that problem?..britrailer.boy iwould like to see how that smoke unit is wired up..I got one too to got with the EOB setup..wished there was instrutions on those smoke units..

The only way I can see the tach reader doing something like this is if a component on it starts to oscillate at some point and sends lots of pulses to the EOB board, that would effectively shut down the speed control.  There is an LM358 op-amp on the board, I suppose it could be doing something odd...

Joseywales,

 

I have a set of (rather dog-eared) instructions for a TAS turbosmoke unit which I recently installed in a Williams brass 4-6-2 that I gutted and rebuilt with an ERR Cruise Commander/RS4 I can scna these and post them if you want them. The ERR Turbosmoke installation was pretty straightforward - 3 wires (AC hot, Ground, Chuff signal from RS4. Unfortunately, the Turbosmoke unit on my 3rd Rail Berk is buried inside the shell and I can't see exactly how it's wired but there are 3 wires from the locomotive harness leading to it.

 

 

Here are pictures of the EOB motherboard and the motor/tach sensor.

 

Let me know if you need more to help me identify/solve the problem.

Frank

I'd like a copy, can you attach them to a post here?  Even better, there is a pinned thread in the TMCC/Legacy forum for documentation, that would be a good place to put them.

Here's one debugging idea.  Try running it in conventional mode and see if it has the same issue.  Next, refer to the diagram below and install a jumper across the cruise on/off switch and run it in conventional.  See if either of those options results in normal operation.

 

 

I'll scan the Turbosmoke instructions and post them to this thread and the documentation thread.

For the conventional mode tests, I'll have to dig out an old transformer from my junk box.

 

I'll let you know the results.

Are you just running with a brick now?  The conventional tests should tell us if it's a speed control issue or perhaps the drivers are turning off for some reason.

I've had to replace the drivers on a couple of these, one self-inflicted by letting a wire get away from me, the other was probably a shorted motor lead, but I don't know for sure.




That would be great, always handy to have those when questions come up.

I tried the conventional mode tests.

 

Basically, nothing happened.

 

I started with "cruise on". As I increased power, the lights came on and I got a faint buzz from the speaker. At 17vac, one brief interruption of power produced a click but no movement.

 

With "cruise off" same result.

 

Does this tell you anything?

Gunrunnerjohn,

As promised, here is the TAS Turbosmoke installation instruction booklet (also posted on the 'reference materials' thread).

Do you have any further thoughts on my 'speed restriction' problem?

Any suggestions will be very welcome.

At this point I would try and determine if its the motor or the board. If you have a DC power pack or a diode bridge to convert AC to DC you could apply the DC directly to the motor leads gradually ramping up the voltage. Do this with the tether disconnected of course. Its a long shot, I know, but without detailed schematics of the board it would be hard to tell what is failing. If the motor comes up to speed then you know for sure there is a problem with the board.

 

Pete

Thanks Norton,

 

I'll give it a try.

look at this thread..sounds alittle like yours?

https://ogrforum.com/t...b-signal-sensitivity

Thanks for the Turbosmoke instructions, that should answer a few questions.

Joseywales,

Thanks for pointing out the other EOB thread and the resolution.

 

Both of my 3rd Rail engines (I also have a Mogul) have the antenna connected to the tender chassis. All the literature I've seen says that grounding the antenna is a killer - is that a myth or, are 3rd Rail engines wired up differently to Lionel engines?