308 error / bachmann econami n scale /solved

craftech Mar 19, 2021

  1. FlightRisk

    FlightRisk TrainBoard Member

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    Well, you make me blush ;) Thank you for taking the time to offer your experience and your thanks. The feedback we get from people is really, really rewarding. If it goes to my head, Ash will slap me ;)
     
  2. Mark Ricci

    Mark Ricci TrainBoard Member

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    Hi Ash,

    In anticipation of a Raspberry Pi 4 being delivered tomorrow (for JMRI). Getting some things ready.. Very exciting!!

    However here are a few answers.

    A-(With and without ESP wifi shield and ESP separate nic (as mentioned on the DCC++EX site) and power adapter.
    First Round -Late last year
    Arduino branded Mega and Motor Shield
    2nd Round - Mid Spring
    Elegoo Mega and DIY Motor Shield
    3rd (current)
    Elegoo Mega and Deek Robot

    B-Throughout testing-used brand new dual output 12V@2A and 5V@2A (5V not connected) power supply.

    C-Also have bought the DCC++ EX recommended Ledmo 12V @5A for the layout but have not used for programming.

    D-All Testing done with separate 9V 1A PS for Mega and Motor Shield logic and the 12V @2A connected to Vin of Motor shield. Outside Dupont wires for wifi, no other connections exist.

    E-Same JMRI windows 10 version 4.22 on both computers used in testing.

    F-I'll measure AC, but a little more info.... Using 12V@2A on layout, and measuring DC individually from either rail to motor shield ground, very little change in output voltage. The load during this testing, back in March (Elegoo Mega, DIY Shield + wifi), was varied by running one loco at test points 100, 75, 50, 25% and 0% throttle levels with and without sound and/or LEDs loco lights while having another idle with LED and sound. And in the end, both locos running sound and leds with worst case only down 120mV. I'm a DCC novice but for example, assuming filter components are selected properly so that ripple is held in check, this should be more than satisfactory as it hovers no more than 1% loading. It would seem to point that the 12V @2A supply should be sufficient to program at 250ma.

    In preparation for the PI, I plan on swapping out the layout Mega and DIY shield (will be updating to 3.1 before setting up with Pi, with the test (mega and Deek robot-(ultimately the programming base station to eliminate separate programming track on layout). If you think there is some value, I'd be most happy to perform ACK tests on either or both base stations. Please advise..

    Assuming time permits later this afternoon, I'll get going with the ACK tests.

    Generally visit the DCC++EX site 2-3x a week for updated info.

    Thanks so much for all the help...
     
  3. Mark Ricci

    Mark Ricci TrainBoard Member

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    Additional Info.
    Prog Track AC Measurement (no load) - 26V
    Prog Track AC Measurement with LOCO (After Execution below) - 23.3
    <1 PROG>
    <D ACK ON>
    <R 8 1 1>

    The concern is although think that the AC rms measurement value is good for reference and comparison, the A-D converter is designed to measure AC and report it's rms value. The properties of a sine wave are different and how accurate the DMM reports the true value of a non-sinusoidal wave is questionable.

    JMRI log during execution...Before revision of mysetup.h-currently at 10700
    Status Cmd
    Power Status: OFF
    Status:Station: DCC-EX, Build: 4a2513d, Version: 3.1.0
    Read Track Current Cmd
    Meter reply: name CurrentMAIN, value 0.00, type C, unit Milli, min 0.00, max 1997.00, resolution 1.00, warn 1997.00
    Current: 0 / 1024
    Track Power ON Cmd
    Power Status: Name:pROGStatus:ON
    Read Track Current Cmd
    Meter reply: name CurrentMAIN, value 0.00, type C, unit Milli, min 0.00, max 1997.00, resolution 1.00, warn 1997.00
    Current: 0 / 1024
    Unknown Message: 'D ACK ON'
    Read Track Current Cmd
    Meter reply: name CurrentMAIN, value 0.00, type C, unit Milli, min 0.00, max 1997.00, resolution 1.00, warn 1997.00
    Current: 0 / 1024
    Status Cmd
    Power Status: OFF
    Status:Station: DCC-EX, Build: 4a2513d, Version: 3.1.0
    Read Track Current Cmd
    Meter reply: name CurrentMAIN, value 0.00, type C, unit Milli, min 0.00, max 1997.00, resolution 1.00, warn 1997.00
    Current: 0 / 1024
    Prog Read Cmd: CV: 8, Callback Num: 1, Callback Sub: 1
    Unrecognized reply: '* ACK baseline=3/8mA Threshold=23/68mA Duration between 4000us and 10700us *'
    Unrecognized reply: '* V0 cv=8 bit=7 *'
    Unrecognized reply: '* ACK after 79mS max=67/200mA pulse=10556uS samples=90 gaps=0 *'
    Unrecognized reply: '* V0 cv=8 bit=6 *'
    Unrecognized reply: '* ACK after 84mS max=63/188mA pulse=10440uS samples=142 gaps=0 *'
    Unrecognized reply: '* V0 cv=8 bit=5 *'
    Unrecognized reply: '* NO-ACK after 144mS max=5/14mA pulse=0uS samples=75 gaps=0 *'
    Unrecognized reply: '* V0 cv=8 bit=4 *'
    Unrecognized reply: '* ACK after 30mS max=60/179mA pulse=10324uS samples=63 gaps=0 *'
    Unrecognized reply: '* V0 cv=8 bit=3 *'
    Unrecognized reply: '* ACK after 28mS max=54/161mA pulse=10440uS samples=60 gaps=0 *'
    Unrecognized reply: '* V0 cv=8 bit=2 *'
    Unrecognized reply: '* NO-ACK after 143mS max=3/8mA pulse=0uS samples=75 gaps=0 *'
    Unrecognized reply: '* V0 cv=8 bit=1 *'
    Unrecognized reply: '* NO-ACK after 144mS max=1/2mA pulse=0uS samples=76 gaps=0 *'
    Unrecognized reply: '* V0 cv=8 bit=0 *'
    Unrecognized reply: '* ACK after 29mS max=63/188mA pulse=10440uS samples=61 gaps=0 *'
    Unrecognized reply: '* VB cv=8 value=38 *'
    Unrecognized reply: '* ACK after 28mS max=56/167mA pulse=10556uS samples=68 gaps=0 *'
    Unrecognized reply: '* Callback(38) *'
    Program Reply: Callback Num: 1, Callback Sub: 1, CV: 8, Value: 38
    Read Track Current Cmd
    Meter reply: name CurrentMAIN, value 0.00, type C, unit Milli, min 0.00, max 1997.00, resolution 1.00, warn 1997.00
    Current: 0 / 1024
    Read Track Current Cmd
    Meter reply: name CurrentMAIN, value 0.00, type C, unit Milli, min 0.00, max 1997.00, resolution 1.00, warn 1997.00
    Current: 0 / 1024
    Status Cmd
    Power Status: OFF
    Status:Station: DCC-EX, Build: 4a2513d, Version: 3.1.0
    Read Track Current Cmd
    Meter reply: name CurrentMAIN, value 0.00, type C, unit Milli, min 0.00, max 1997.00, resolution 1.00, warn 1997.00
    Current: 0 / 1024


    *****After updating to 11000
    Unknown Message: 'D ack on'
    Read Track Current Cmd
    Meter reply: name CurrentMAIN, value 0.00, type C, unit Milli, min 0.00, max 1997.00, resolution 1.00, warn 1997.00
    Current: 0 / 1024
    Prog Read Cmd: CV: 8, Callback Num: 1, Callback Sub: 1
    Unrecognized reply: '* ACK baseline=3/8mA Threshold=23/68mA Duration between 4000us and 11000us *'
    Unrecognized reply: '* V0 cv=8 bit=7 *'
    Unrecognized reply: '* ACK after 29mS max=62/185mA pulse=10672uS samples=59 gaps=0 *'
    Unrecognized reply: '* V0 cv=8 bit=6 *'
    Unrecognized reply: '* ACK after 28mS max=62/185mA pulse=10440uS samples=64 gaps=0 *'
    Unrecognized reply: '* V0 cv=8 bit=5 *'
    Unrecognized reply: '* NO-ACK after 143mS max=9/26mA pulse=0uS samples=75 gaps=0 *'
    Unrecognized reply: '* V0 cv=8 bit=4 *'
    Unrecognized reply: '* ACK after 29mS max=63/188mA pulse=10440uS samples=63 gaps=0 *'
    Unrecognized reply: '* V0 cv=8 bit=3 *'
    Unrecognized reply: '* ACK after 28mS max=51/152mA pulse=10440uS samples=62 gaps=0 *'
    Unrecognized reply: '* V0 cv=8 bit=2 *'
    Unrecognized reply: '* NO-ACK after 145mS max=6/17mA pulse=0uS samples=76 gaps=0 *'
    Unrecognized reply: '* V0 cv=8 bit=1 *'
    Unrecognized reply: '* NO-ACK after 144mS max=2/5mA pulse=0uS samples=76 gaps=0 *'
    Unrecognized reply: '* V0 cv=8 bit=0 *'
    Unrecognized reply: '* ACK after 29mS max=57/170mA pulse=10208uS samples=62 gaps=0 *'
    Unrecognized reply: '* VB cv=8 value=38 *'
    Unrecognized reply: '* ACK after 29mS max=62/185mA pulse=10324uS samples=68 gaps=0 *'
    Unrecognized reply: '* Callback(38) *'
    Program Reply: Callback Num: 1, Callback Sub: 1, CV: 8, Value: 38
    Read Track Current Cmd
    Meter reply: name CurrentMAIN, value 0.00, type C, unit Milli, min 0.00, max 1997.00, resolution 1.00, warn 1997.00
    Current: 0 / 1024
    Status Cmd
    Power Status: OFF

    JMRI reading LOCO Basic Sheet for the first time - No Errors, and after 3 runs, 100% AOK - YEAH!!
    A couple of questions....

    Curious.. Is there some sort of ratio using these ACK MAX, ACK Limit and maybe another in an effort to minimize loco movement during programming? Again curious only, as these changes definitely works for me.

    Went ahead and added Limit 50 seem to be faster running 3 commands.. Also, while JMRI reported a 308 1st attempt, it completed. Thinking maybe spot on track cuz the next 3 runs were flawless and and appeared to run thru the fastest yet!!!
    Status:Station: DCC-EX, Build: 4a2513d, Version: 3.1.0
    Read Track Current Cmd
    Meter reply: name CurrentMAIN, value 0.00, type C, unit Milli, min 0.00, max 1997.00, resolution 1.00, warn 1997.00
    Current: 0 / 1024
    Read Track Current Cmd
    Meter reply: name CurrentMAIN, value 0.00, type C, unit Milli, min 0.00, max 1997.00, resolution 1.00, warn 1997.00
    Current: 0 / 1024
    Read Track Current Cmd
    Meter reply: name CurrentMAIN, value 0.00, type C, unit Milli, min 0.00, max 1997.00, resolution 1.00, warn 1997.00
    Current: 0 / 1024
    Prog Read Cmd: CV: 8, Callback Num: 1, Callback Sub: 1
    Unrecognized reply: '* ACK baseline=1/2mA Threshold=17/50mA Duration between 4000us and 11000us *'
    Unrecognized reply: '* V0 cv=8 bit=7 *'
    Unrecognized reply: '* ACK after 55mS max=71/212mA pulse=10788uS samples=89 gaps=0 *'
    Unrecognized reply: '* V0 cv=8 bit=6 *'
    Unrecognized reply: '* ACK after 29mS max=68/203mA pulse=10788uS samples=63 gaps=0 *'
    Unrecognized reply: '* V0 cv=8 bit=5 *'
    Unrecognized reply: '* NO-ACK after 144mS max=3/8mA pulse=0uS samples=76 gaps=0 *'
    Unrecognized reply: '* V0 cv=8 bit=4 *'
    Unrecognized reply: '* ACK after 29mS max=56/167mA pulse=10788uS samples=64 gaps=0 *'
    Unrecognized reply: '* V0 cv=8 bit=3 *'
    Unrecognized reply: '* ACK after 29mS max=59/176mA pulse=10904uS samples=65 gaps=0 *'
    Unrecognized reply: '* V0 cv=8 bit=2 *'
    Unrecognized reply: '* NO-ACK after 144mS max=1/2mA pulse=0uS samples=76 gaps=0 *'
    Unrecognized reply: '* V0 cv=8 bit=1 *'
    Unrecognized reply: '* NO-ACK after 144mS max=1/2mA pulse=0uS samples=76 gaps=0 *'
    Unrecognized reply: '* V0 cv=8 bit=0 *'
    Unrecognized reply: '* ACK after 29mS max=55/164mA pulse=10788uS samples=64 gaps=0 *'
    Unrecognized reply: '* VB cv=8 value=38 *'
    Unrecognized reply: '* ACK after 29mS max=58/173mA pulse=10788uS samples=69 gaps=0 *'
    Unrecognized reply: '* Callback(38) *'
    Program Reply: Callback Num: 1, Callback Sub: 1, CV: 8, Value: 38
    Status Cmd
    Power Status: OFF

    Thank you!!!!!!
    One other thing throughout all this that may be useful for others.. Have thread regarding double crossover stutter in 1 direction. Both brand new BLI F3 and Atlas gold SD35 ran terribly thru turnouts. A couple of months ago, nearing the end of the line about to throw layout in dumpster, banged into the layout, 4' above hard floor, BLI F3 fell to ground and the 2 trucks broke. Received exchange trucks but b4 installing, not only cleaned pickups, but 1 long side was closer to wheels than the other, bending to equalize and then slightly more to increase pressure. Since then, May 17, it has been operating beyond expectations. Understand any combination of the 4 variables could have impacted the change in performance. Believe this contributed to the problem. Mention this because that a lot of BLI Paragon skuttlebutt regarding contacts. Something that could be issue in attempting to prog BLIs. Just wanted to pass it along...
     
    Ash likes this.
  4. Ash

    Ash TrainBoard Member

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    Using the AC volts scale on my analog meter, I generally see a reading 1 to 2 volts lower than the DC input.

    Glad to see 100% success. I have yet to find the algorithm for ACK tuning. I start with the defaults and check the diags if I see 308 errors.

    RE: loco movement. Some move more. For my short test track, I have a binder clip on one rail and a soft eraser -- start with the loco against the eraser/clip, positioned to avoid damage to the coupler.

    With JMRI 4.23.5 or higher, those lines would appear like this:
    DIAG: VB cv=8 value=38
    DIAG: ACK after 29mS max=58/173mA pulse=10788uS samples=69 gaps=0
     
    Mark Ricci likes this.
  5. BigJake

    BigJake TrainBoard Member

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    Please note that inexpensive multimeters approximate RMS (root-mean-squares) measurements of AC wave forms by assuming it is a sinewave and scaling a series of measurements accordingly. This is not accurate for non-sinusoidal waveforms (e.g. household AC voltage is sinusoidal, DCC waveforms are NOT).

    Besides that, even many "True RMS" reading multimeters do not sample fast enough to accurately compute the RMS of fast square-waves, perhaps including DCC, especially waveforms that "ring" a lot.

    As such, a voltage reading of the DCC waveform from most anything but an oscilloscope should be considered a figure of merit, not absolute truth, and only directly comparable with other measurements from the same model of multimeter.
     
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  6. Mark Ricci

    Mark Ricci TrainBoard Member

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    Absolutely BigJake! Exact point I was making before. Both meters measure AC 120 line at correct value. Below shows their reaction to PWM. Even upper end Flukes would have issues. Don't you love the classic Eico 100A4 VOM. Of course it had trouble too! Ah, D'Arsonal meter movements, voltmeter multipliers and ammeter shunts... This stuff is so great! Now I'm a bit upset with myself for selling the dual channel 20 Mhz scope a while back... :-(

    Definitely like the format on the test version you are using. Probably will wait for the expected production 4.23.7 due out soon.

    New to DCC and only have 2 locos - unaware whether the movement during programming is generally normal or is a symptom of a decoder or other loco "defect"?

    Ash my sincere thanks in working with those in promoting this. DCC++EX and Arduino have initiated an electronics renaissance for me and just want to say how grateful I am to you guys.

    upload_2021-6-23_6-2-31.png
     
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  7. BigJake

    BigJake TrainBoard Member

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    Yeah, my dad and grandfather were old Hams and had all kinds of old tube equipment (but not an o'scope). My dad had a nice Simpson analog meter which my brother has now. I used Fluke meters at work, and I have one at home. They are good for 99% of what I need, but a scope would be nice. Knowing how to probe is half the battle with digital waveforms, no matter what the voltage. "Keep your signals close and ground closer!"

    Your locomotives moving a little during service mode programming (not "programming on the main, aka "ops mode programming") is normal. The decoder acknowledges/answers commands by pulsing the current load, which is detected by the programmer. Decoders pulse the motor and flash the headlights to generate the current pulses. as well as providing visual cues that the decoder is accepting and responding to commands. Some decoders alternate the direction of the motor pulses so the loco does not go far, but others will walk quite a ways if you read the decoder's entire register set into JMRI Decoder Pro!
     
    Mark Ricci likes this.
  8. Mark Ricci

    Mark Ricci TrainBoard Member

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    How did you guess? Been an Amateur Radio license holder for 40+ years. My first radio was a pre-WW2 Hallicrafters Skybuddy. Donated just about all of my electronics stuff to local HAM club b4 moving to FL including a couple of Simpson 260s. Solid and Definitely workhorses. Don't remember why I kept the Eico??
    Couldn't say it better myself. Don't have the isolation transformer anymore either. :) Essential for using scope or other test eq with a grounded input when measuring above ground...

    Thank you for the insight regarding the loco movement during programming. Using just a few pieces of track, JMRI on Windows PC and a separate DCC++EX base in the office for service mode programming. Only tested reading basic sheet so guessing movement could be pretty far 10-12"??? if reading all the sheets. Is there ever a time when its necessary to read all the sheets?? Thank you.
     
  9. BigJake

    BigJake TrainBoard Member

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    If you put bumpers on either end of the programming track, the loco will just spin its wheels a bit when pulsing the motor at the end of the track, but at least it will stay on the track.

    Another choice is a treadmill (aka "rollers"), if you don't have room for a small test/programming loop.

    But a test loop is invaluable for speed-matching locos that will be consisted together. Some folks use programming-on-the-main (ops-mode programming) and speed-match on the layout (assuming the layout is/has a loop).
     
    Mark Ricci likes this.
  10. Mark Ricci

    Mark Ricci TrainBoard Member

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    Thank you... Is there ever a time when its necessary or required to read and/or write all the sheets in JMRI for decoder?
     
  11. BigJake

    BigJake TrainBoard Member

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    I read all of mine into DP, but I don't use sound decoders, so their register contents are smaller. It still makes one of my loco's circle the dining room table half again.

    The reason is, so that if anything goes wrong with the decoder, I can restore it (or a new one of the same brand/type) back to the same settings.

    I have not yet had to use this feature to restore a decoder. knock knock...

    Besides the much better programming user interface than any throttle can provide, it's one of JMRI DP's best features, IMHO.
     
    Mark Ricci likes this.
  12. Mark Ricci

    Mark Ricci TrainBoard Member

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    A form of backup--- didn't think about since have not changed CVs other than addr. Some day.. Yes, can see that is very useful..

    Oh, no doubt! Right from the getgo DP was the only way I was planning on programming. Thanks!
     
  13. Mark Ricci

    Mark Ricci TrainBoard Member

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    Interesting......
    Bought a backup DIY motor shield and for fun, swapped out the Deek robot motor shield on same Uno and code (Ash helped me on with no 308 errors). Many 308 errors.. Put the Deek robot back, no issues. Another variable to the 308 issue equation for consideration besides loco decoder though hate to draw a conclusion with a sample of 1. Going to try additional DIY and Deek robot shields.

    Curious whether my OPs base, a Mega and DIY Motor shield that powers the layout(OPS only), have not yet attempted to program via that system. interested in determining whether this is some sort of anomaly with the DIY shields or not. Actually planning on doing this next. Wanted to pass additional observation along. Has or is any pattern developing that suggests higher instances of 308 errors when using one of the 3 popular Arduino branded Shield, Deek Robot and DIY as compared to the others assuming all other variables are the same eg. decoder, Arduino code, myconfig, mega-uno(?), power supply, track....
     
  14. Ash

    Ash TrainBoard Member

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    The 'DIY More L298NH' is listed as a supported motor shield. https://dcc-ex.com/reference/hardwa...ghlight=diy more#diy-more-l298nh-motor-shield

    I don't have experience with the board; current sensing might be different (or defective). There is also a slight difference in the location of some of the pins and how they protrude from the bottom -- make sure that they are not shorting against the USB connector.

    Did you save some of the diagnostics?
    <1 PROG>
    <D ACK ON>
    <R>
    <R 8 1 1>

    Also good to see the initial startup report.
    <D RESET>
     
    Mark Ricci likes this.
  15. FlightRisk

    FlightRisk TrainBoard Member

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    I have one of those boards, I'll test it on an Uno.

    UPDATE: We tested this board in the past which is why it is one of the boards we know works. So I went to the "lab" with a known, standard test track setup and compared it to a Deek-Robot Motor Shield. It is well within spec. There is a bit of a tolerance on all the boards we find, so even between the same brand, there can be differences. The IBT_2 and some of the Pololu current sense boards can be so different, it is best to calibrate them.

    So here I test with known resistor packs that sit on the track along with an Ammeter measuring the current usage of the motor shield. There was no significant difference between the current reporting or performance of the 2 shields. For example, one test using the main track showed the Deek-Robot using 1.12A and averaging about 1.27Amp reported with the <c> command. The DIY More put out a bit more current at 1.2A and reflected that with about 1.3A reported. That is about the limit of either board without a heat sink and a cooing fan. At the lower end, for 100mA, the DR was reporting around 113 and the DIY was showing me 107. I could use these values to calibrate the current sense reporting, but we really just need an idea that we aren't approaching the limit of the board and to have short circuit detection, so that's an unnecessary effort.

    Using the <D ACK ON><R> It read an N-Scale sound Loco 100% of the time. I didn't try other locos, but this one uses about 32mA idling with its diesel noises (if I turn power on with <0>. I tried it with auto-power-on-programming also) and it was registering 500mA pulses. A bit of overkill ;)

    So try the <R> test with ACK diagnostics on and let us know what you find. I sometimes find a wire loose, bent pin, or have a non-sound loco that isn't seated on the track. That's why I like testing with sound locos and turning both tracks on. The current meter in JMRI is also helpful. You shouldn't have 0 Amps showing on the main track if the power is on and a loco is on the track.

    Fred
    DCC-EX
     
    Last edited: Jul 14, 2021
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  16. Mark Ricci

    Mark Ricci TrainBoard Member

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    Thank you for the input. Sorry, just saw this today. Only have 2 locos, both with DCC sound and this issue only on the BLI P3. The DIY works flawlessly in OPS and issue only when attempting to prog BLI. When checked last, the Loksound select in Atlas loco programmed with either shield with no problem. Decided to go with the DIY cuz of the 298HN package better heat dissipation because of the slightly better values as you have confirmed.

    Slightly different tangent question???
    Since using DIY for OPS, outside programming needs, hoping that it has sufficient power to drive Digitrax DS64(with D-crossover) directly from shield's track output. In parallel with the shield's track output, a TAM VAlley DAB002 will be inserted which will be connected to track to power loco's. Any thoughts on the DIY (or Deek Robot) driving DS64 assuming no locos drawing power??
     
  17. FlightRisk

    FlightRisk TrainBoard Member

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    The DS64 says that at 14V, it's max current is 300mA. So that's not a problem forn the DIY which will do about 1.2A (more with a heat sink and fan). Digitrax does recommend an external supply if you have more than one. So you can always use track power and use DCC to control things, or you can have a separate bus.
     
  18. Mark Ricci

    Mark Ricci TrainBoard Member

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    Thank you Fred for reply. I don't have a DS64 yet to try so before ordering booster(s), 1 or 2 needed??? was hoping maybe somebody tested.

    Want to use DS64 across base station (DIY Shield) track output and a TAM valley booster input connected to the base station track output as well. Tam Valley output to track bus. Kinda of curious as worse case condition is one DS64 output will be connected to drive Double Crossover and throwing its 4 solenoids at one time. Figured that motor shield 1.2 A could suffice assuming the track and running decoders are powered via booster effectively placing no load across the shield output?? Added plus is track shorts are isolated from shield output keeping the DCC signal to the DS64??

    System is JMRI Pi 4 with DCC++EX base so my understanding is unless Loconet is used, the DS64 must be powered by track. Fortunately, only have 4 switches so 1 DS64 is plenty... Thank you.
     
  19. FlightRisk

    FlightRisk TrainBoard Member

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    It is true that if you just connect the output of the CS to the Tam Valley Booster(or boosters), then you really aren't loading down the command station very much. They use a 6N137, which is an optoisolator connected to the track and uses about 5mA according to their spec sheet. I get 8mA, but not much difference. The booster is rated for 3A continuous power, which also would power 10 DS64s.

    But, you don't have to even have a motor shield. You can send the DCC signal to that booster directly from the signal pin of the Arduino. 5V is enough to trigger the optoisolator. So for the STANDARD_MOTOR_SHIELD in your config.h (the default), you connect pin 12 to one side of the DCC input and ground of the Arduino to the other. If the led lights, switch them around since you would only be sending positive pulses instead of the full DCC bi-polar signal. So when it is working, it lights the LED inside the optoisolator. Since there is no negative pulse to be shunted/half rectified, the DCC signal led near the screw terminals won't light. You can only use one or 2 boosters connected this way because the Arduino can only source a max of 40mA. But I imagine the first booster can be rigged for track output and connected to the others configured as accessory boosters. Just a thought, hope it isn't TMI. In any case, no need for any more than a 10V DC power supply into the motor shield if you use that since you just have enough current to run the input of the optoisolator (5mA), though 12 or 14 won't hurt anything.

    I don't know what's inside the DS64, but since it says it only uses a max of 300mA, that is probably inrush current if there is a capacitors charging or if it is directly energizing a solenoid. If it is the same circuit as their DS52 2 turnout decoder, it charges a big capacitor and switches it with MOSFETs to energize the coils. As you said, if the track shorts, you have 5 minutes to fix it before the DS64 cuts power to the accessories too. And you are right about needing power from the track or a booster since that is how it gets its commands (DCC) if you aren't using Loconet.
     
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  20. Mark Ricci

    Mark Ricci TrainBoard Member

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    Thank you for the info. Assuming shield output can drive DS64 and D-xover, there does not seem to be any advantage of buying a 2nd booster since already have the DIY shield, unless at the moment solenoids go off trips the shield or causes significant loading thereby adversely impacting DCC signal supplied to the track via the booster. Thinking then of buying just 1 TAM DAB002 Booster for track.

    Currently using the Ledmo 12V 5A DC power supply as recommended on the DCC EX site. It supplies sufficient power to track via Vin of shield, it is used to power the D xover and other switches, powers the Pi and Arduino logic (via 12V-5V Buck). For the first time the locos don't "feel" that instantaneous load when throwing the D Crossover. Also running structure lighting (current draw estimate 10 mA) via the Pi's 5V and GND GPIO pins.

    Mention all this cuz it would appear that the Ledmo 12V 5A, even with adding the DS64 and DAB002 booster, should suffice since the Booster will draw only what's needed based on locos running. Any thoughts?
     
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