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Post by superwarp1 on Oct 23, 2024 23:52:48 GMT
WHAT, where does the spike come from when there’s a short? I can tell you it’s not in the engine It's not a matter of the source, it's a matter of what you want to protect. The waveforms generated by derailments, sparks, and shorts are very irregular. When these happen, the load is varying and as resistance, and inductance change, the voltage can swing all over the place. Where at one spot in the circuit, near the derailment the voltage could be exceedingly high, another spot near the transformer could be at the zero crossing. The TVS will do your engine electronics no good there. If the spike waveform repeats long enough then yes the TVS will shut the current to ground, which may or may not cause the circuit breaker to trip depending on the duration. However, by that time the damage to the sensitive electronics is done. Again, TVS devices need to be within inches to centimeters away from the circuitry to protect it against the wild varying high frequency waveforms that are the result of rapid loading and unloading of the transformer. Again we’ll have to agree to disagree. 
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Post by steveoncattailcreek on Oct 24, 2024 2:18:53 GMT
It's not a matter of the source, it's a matter of what you want to protect. The waveforms generated by derailments, sparks, and shorts are very irregular. When these happen, the load is varying and as resistance, and inductance change, the voltage can swing all over the place. Where at one spot in the circuit, near the derailment the voltage could be exceedingly high, another spot near the transformer could be at the zero crossing. The TVS will do your engine electronics no good there. If the spike waveform repeats long enough then yes the TVS will shut the current to ground, which may or may not cause the circuit breaker to trip depending on the duration. However, by that time the damage to the sensitive electronics is done. Again, TVS devices need to be within inches to centimeters away from the circuitry to protect it against the wild varying high frequency waveforms that are the result of rapid loading and unloading of the transformer. Again we’ll have to agree to disagree. That's a non-answer, to an issue with, I believe, a reasonably knowable answer. You seem to feel that, no matter the location of the physical disruption (short, etc.), the potentially damaging voltage spike will *always* emanate directly from the power source (the transformer), and not from the point of disruption. If that is true, then, yes, a TVS directly across the transformer terminals stands the best chance to nip the spike before it can propagate outward to the vulnerable circuit boards. I am not a scholar of such matters, but that is not my understanding of the sole possible cause or origin of voltage spikes. If I am correct, then a TVS across the transformer terminals may or may not provide adequate spike suppression for any vulnerable PCBs. OTOH, placing the TVS directly across the point of vulnerability will *absolutely* provide the maximum protection for that particular PCB, regardless of the point source of the spike or which of us is correct. That's not opinion, just logic and fact. Yeah, it's somewhat inconvenient to have to open each item of rolling stock with a circuit board and solder in a TVS, but IMHO that's still a lot less inconvenient than having to find replacement parts before replacing a burned-out board. YMMV . . .
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Post by superwarp1 on Oct 24, 2024 11:45:35 GMT
Again we’ll have to agree to disagree. That's a non-answer, to an issue with, I believe, a reasonably knowable answer. You seem to feel that, no matter the location of the physical disruption (short, etc.), the potentially damaging voltage spike will *always* emanate directly from the power source (the transformer), and not from the point of disruption. If that is true, then, yes, a TVS directly across the transformer terminals stands the best chance to nip the spike before it can propagate outward to the vulnerable circuit boards. I am not a scholar of such matters, but that is not my understanding of the sole possible cause or origin of voltage spikes. If I am correct, then a TVS across the transformer terminals may or may not provide adequate spike suppression for any vulnerable PCBs. OTOH, placing the TVS directly across the point of vulnerability will *absolutely* provide the maximum protection for that particular PCB, regardless of the point source of the spike or which of us is correct. That's not opinion, just logic and fact. Yeah, it's somewhat inconvenient to have to open each item of rolling stock with a circuit board and solder in a TVS, but IMHO that's still a lot less inconvenient than having to find replacement parts before replacing a burned-out board. YMMV . . . Well since you went there, I'll go there just this once. I'm not saying installing a tranzorb in every engine wouldn't work, I'm saying it's not necessary. Go ahead and void warranties, and take the time to dissemble every engine to install. Anyone who knows physics, knows that transformers hate a change in state, when a short occur the spike gets generated in the transformer to try to reverse this change in state. Clamping it at the source is the best option. Since electrons or voltage moves near the speed of light, what's a few feet going to matter? 
If you watched my videos on the PSX electronic circuit breakers which I guess you didn't. Not only does the PSX clamp the voltage it also clamps the current. Arch welding wheels to track is a thing of the past with these installed.
And since you may think I'm full of !@#$ and don't know what I'm talking about. Being a Avionics/Electronics with a tech for 35 years with a degree in electronic technology, licensed by the FAA. Protecting aircraft and other equipment from Lightning strikes and other conditions, plus dealing with transorbs longer than anyone in this hobby has even heard about them. I think I know and since I've installed my current setup, I have yet to blow any electronics in any engine.
Last point, what if the tranzorb blows protecting your engine? I've seen more blown tranzorbs than I can shake a stick at and tranzorbs when they go bad don't always short, they sometimes blow open and then your engine is unprotected. So take your engine apart again to replace, easier if it's wired across the track or your power source.
There, that's it, I doubt I'll change anyone's minds. That's why I didn't respond, why waste the oxygen. So time to go back to work. Peace 
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Post by bobthetrainguy on Oct 24, 2024 19:22:53 GMT
That's a non-answer, to an issue with, I believe, a reasonably knowable answer. You seem to feel that, no matter the location of the physical disruption (short, etc.), the potentially damaging voltage spike will *always* emanate directly from the power source (the transformer), and not from the point of disruption. If that is true, then, yes, a TVS directly across the transformer terminals stands the best chance to nip the spike before it can propagate outward to the vulnerable circuit boards. I am not a scholar of such matters, but that is not my understanding of the sole possible cause or origin of voltage spikes. If I am correct, then a TVS across the transformer terminals may or may not provide adequate spike suppression for any vulnerable PCBs. OTOH, placing the TVS directly across the point of vulnerability will *absolutely* provide the maximum protection for that particular PCB, regardless of the point source of the spike or which of us is correct. That's not opinion, just logic and fact. Yeah, it's somewhat inconvenient to have to open each item of rolling stock with a circuit board and solder in a TVS, but IMHO that's still a lot less inconvenient than having to find replacement parts before replacing a burned-out board. YMMV . . . Well since you went there, I'll go there just this once. I'm not saying installing a tranzorb in every engine wouldn't work, I'm saying it's not necessary. Go ahead and void warranties, and take the time to dissemble every engine to install. Anyone who knows physics, knows that transformers hate a change in state, when a short occur the spike gets generated in the transformer to try to reverse this change in state. Clamping it at the source is the best option. Since electrons or voltage moves near the speed of light, what's a few feet going to matter?
If you watched my videos on the PSX electronic circuit breakers which I guess you didn't. Not only does the PSX clamp the voltage it also clamps the current. Arch welding wheels to track is a thing of the past with these installed.
And since you may think I'm full of !@#$ and don't know what I'm talking about. Being a Avionics/Electronics with a tech for 35 years with a degree in electronic technology, licensed by the FAA. Protecting aircraft and other equipment from Lightning strikes and other conditions, plus dealing with transorbs longer than anyone in this hobby has even heard about them. I think I know and since I've installed my current setup, I have yet to blow any electronics in any engine.
Last point, what if the tranzorb blows protecting your engine? I've seen more blown tranzorbs than I can shake a stick at and tranzorbs when they go bad don't always short, they sometimes blow open and then your engine is unprotected. So take your engine apart again to replace, easier if it's wired across the track or your power source.
There, that's it, I doubt I'll change anyone's minds. That's why I didn't respond, why waste the oxygen. So time to go back to work. Peace Hook a scope to the brushes of a motor spinning at a medium speed while driving a load. Set it to trigger and hold and set your trigger to double the applied voltage, the y-axis to something close to the applied voltage per division, and an x-axis of 2ms/div. Now disconnect the power to both terminals and after you read the scope, come back and we'll chat. |
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Post by trainman9 on Oct 25, 2024 14:33:35 GMT
Isn’t it true that when a short occurs and a circuit breaker is activated that the circuit breaker should be replaced. On the other hand, isn’t it true that a circuit breaker has a lifespan and after a time they lose their effectiveness.
In other words they become less effective over time.
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Post by steveoncattailcreek on Oct 25, 2024 14:57:08 GMT
Isn’t it true that when a short occurs and a circuit breaker is activated that the circuit breaker should be replaced. On the other hand, isn’t it true that a circuit breaker has a lifespan and after a time they lose their effectiveness.
In other words they become less effective over time. I don't think I've ever heard that, and can't think of why that might be true. On one level, I think you may be confusing circuit breakers with simple fuses, which are designed to, well, *fuse* when overloaded, and burn out, opening the circuit and protecting the system from a prolonged overload. Those do in fact have to be replaced after each use. By contrast, circuit breakers are designed to be reset after opening during an overload. I suppose some manufacturer might try to cheap out and build circuit breakers so poorly built that they degrade over time as you suggest, but I've never experienced anything that would support your suggestion. Thermal circuit breakers are relatively cheap, but with the cost of the much more expensive "instant" breakers, replacing them every time they "pop" would likely be prohibitive, and at minimum would be very inconvenient.
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Post by trainman9 on Oct 25, 2024 18:14:47 GMT
Did a search and depending on the source, circuit breakers can last 20-30 years or 30-40 years. The longevity depends on several factors including how many times the circuit breaker is activated. The more they are activated the shorter the lifespans.
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Post by twincities on Oct 26, 2024 15:43:49 GMT
need some help  antenna 2 black wires from rcmc which is correct connector at pcb at cab control area with the red knobs etc it was loose before i knew where it came from not a good day easy part was r&r rcmc board or is there a wiring schematic somewhere on lionel's website |
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Post by twincities on Oct 26, 2024 19:09:40 GMT
as to where the antenna connects to I figured it out and big boy is alive again checked batting for dual smoke unit and blow down all good so didn't bother with whistle steam so the baby oil is working fine after a years use batting not burnt is a brownish color best guess is from high heat these dual smoke units do run hot not being an electronics guru was wondering if old board can be repaired?
I'm waiting on those tvs? diodes to arrive am going to connect at each of 4 blocks hot & ground wires will assume at the source is better than nothing?
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Post by twincities on Oct 27, 2024 12:40:13 GMT
I found wiring diagram for big boy marker lights black connector so how stupid that they do not list what color of wires goes where seeing 2 wires on that connector are black then next terminal is white I'll assume same for 2 wires broken off now how do I get them soldered to there terminals not a huge connector!
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Post by trainman9 on Oct 27, 2024 14:34:32 GMT
Did you get your replacement board?
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Post by twincities on Oct 27, 2024 16:38:04 GMT
Did you get your replacement board? yes I did get new board installed yesterday all was fine till today now when cool engine responds to cab2 commands once warmed up while running I lose all command control from cab2 its sending as i see base flash I tried cab 1 and it was fine then it too lost control when its in this state only option is to power off layout let sit for a few minutes until I can power on again then is okay so Im unsure if rcmc issue an antenna issue or a command base issue or just clean it up and set it as a display piece on top of this black connector for marker lights 2 wires broke off i was able to get soldered back on no easy task seeing connecter is really tiny but i disconnected that connecter just to see if it was the issue and no have same problem with it disconnected power to track at 18 volts this engine has been a nightmare out of the box in 2014 so I'm not sure what the issue is my luck another rcmc board gone or going poof am open to suggestions far as i know the rcmc has radio board etc built in think its time to walk away and come back to this engines issue when im in a better mood as right now a sledge hammer is in my thoughts
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Post by twincities on Oct 28, 2024 16:38:06 GMT
Update this is so crazy!
so new rcmc installed saturday worked fine but never ran it yesterday ran it and all was fine for 10 minutes then engine stopped dead tender sounds medium volume smoke units still smoking but will not respond to any commands from cab-2 legacy base red light flickers to remote key press but remotes red led stays dark power off turn cab-2 off wait 2 minutes turn power on poof all responds to cab-2 again but this is intermittent as sometimes when power applied I think its same as before powering off tender sounds engine powers on immediately but still no response to commands
so today i turned all smoke units and odyssey off ran fine for almost 10 minutes but tried the quillable whistle and within seconds engine comes to a halt and the whistle will not stay going if I hold the lever down it cuts in and out instead of staying on till i release the lever
so i turned all smoke and odyssey back on removed one wire from command base engine ran fine for 20 minutes using the whistle button on transformer ran fine I'm getting the impression the issue is either whistle related or somethings getting to hot but what?
and most times i have to do the eng id number and set then it responds again
anyone know if lionel can test the rcmc board to see if its the issue? is there anything i can unplug be it smoke units to isolate to find root cause?
thanks for any help on this
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Post by trainman9 on Oct 28, 2024 18:19:14 GMT
There was an issue a couple of years ago with the Legacy H10’s. It had something to do with the volume of the whistle. If you had the whistle volume set too high and blew the whistle the engine would stall. Let the engine sit and it would run fine again.
There was a solution but for the life of me I can’t remember what it was except to lower the volume of the whistle. Maybe someone else of this forum may be able to help. Are you on any other model railroad forums. If so, post about the issue and perhaps someone will chime in.
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Post by trainman9 on Oct 28, 2024 18:20:54 GMT
One other thing. Put your old board back in and see if the engine will run. Don’t blow the whistle.
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