Digitrax from Burkhardt

[BobB]

Of the three listed Digitrax dealers here in South Africa, it's probable that John Burkhart from Johannesburg is one of the well known suppliers, not least of all because of his sessions at his home (and shop) running his large HO american outline layout. I'm told his liberal use of expletives knows no bounds when a hapless operator makes a mistake.

I recently purchased a reverse loop module from John (a revision 1 AR1) which did not work when installed. John's reaction (and written comments) are that I was wrong in the way that the layout was wired because his substitution "test" indicated the unit worked.

The fact that he did not take any measurement (calibrated or not) and that he presumed a heavy HO locomotive equated to a small n gauge loco running at virtually minimum speed was superfluous, it had to be my wiring that was at fault !!!!!!!

Whilst I would not suggest that my track laying and power supply systems are ever perfect, with no examination, to be told by John that I am at fault is insulting.

The essence of this narrative is to warn you all. If you buy from John Burjhardt, it would appear that the "No worries" guarantee offered by Digitrax does not apply. But not to worry, we have the consumer protection act here in South Africa.

[Freightcars]

Hi Bob,

Could you give a detailed description of the problem that you're experiencing with the AR1?  I'm guessing its not "tripping" when its supposed to, but could you give some more details.  Also if you could include

AR-1's are generally easy to use.  There are a couple of things one needs to do to get them to work:

• The section of track that the AR-1 controls must be isolated on both rails at both ends of the section
• Your longest train must fit inside the whole auto reverse section
• You may need to set the TTC screw (Turntable Trip Current Adjustment) so that the AR1 trips at the correct time
• It is a good idea to have feeds as close a possible to the isolated gaps as is possible.  Preferably on both sides of the gap.  This helps to make sure that the correct device
• You may need to adjust the trip settings in the command station so that it acts slower than the AR1

The above are just some things that may help off the top of my head.  As I said, more information is needed.

HTH,

Niel

[BobB]

Hi Niel, thank you for your response.

As you say, the AR1 is generally very easy to use. The AR1 would not trip when a test locomotive was run slowly around the loop. The loco in question was a run-in Farish small bo-bo diesel. It would trip albeit with a short being detected when run at higher speed with the lights turned on, therefore needing to draw a higher current. This same locomotive worked on another layout using an AR1 with the AR1's TTC potentiometer remaining set at the as supplied mid point.

The reverse loop was isolated at both ends with insulated joiners to give the required "double gap".
The longest train fitted into the reverse loop.
The TTC was set to the minimum setting (as per the set up instructions)
Initially feeds to the track inside the loop were by wires soldered to the underneath of fish plates. I was using Peco 1st radius set track curves (N gauge) so about 180 mm from the gaps. Outside of the reverse loop one feed was on the end of another curve (so again about 180mm) whilst the other end was closer, about 50 mm.
Initially the controller was not from Digitrax but after the trouble started I reverted to using a DCS51 (Zephyr as they used to be known). Its settings were as supplied brand new.

At the insistence of John I soldered two extra track feeds onto the reverse loop at each end "less than 50mm from the ends". This made absolutely no difference to the operation of the unit. Of coarse, the two curves which were so treated are now 'damaged'.

The unit has been returned. John has written that he tested the unit by substituting it in his layout (Big HO american outline) and that it worked perfectly. Because of this he says the unit is not defective. Perhaps he is right but it did not trip for my little diesel, possibly because the current draw was below the specified 0.25 Amps, or perhaps the unit needs more than that to work. In any event it did not work and neither John nor I know why because no electrical readings have been taken.

I am in the process of modifying the track layout to remove some of the compromises entered into for the purposes of getting the Hornby e-link system to operate. Whilst doing this I will wire the reverse loop to operate using an old fashioned DPDT. Whilst I regard this as a retrogressive step, it overcomes the inability to obtain a working reverse loop module here in South Africa.

[BigEd]

I know John since the 1999 Model Train Conference here in Cape Town. But I know that you can pose your problem straight to Digitrax and they will assist you.

[Freightcars]

Hi Bob,


That the AR-1 needs more current to trip it is unlikely.  Some of the small more modern HO locos are very light on amp draw. I'd suspect that it may be possible that they draw as little as 180ma and these operate flawlessly.  Also coupled to the fact that the same loco has operated on another layout that worked kinda rules this out, barring that your AR1 maybe defective.

Ok, it seems that all the obvious stuff was done right. In theory with everything been correct it should work, but it doesn't 

The only one that may be questionable is the trip setting of the DCS51.  By default it is set 1/8th of a second which can be to fast to give the AR-1 a chance to trip properly.  Try setting Op switch 18 to "closed" to extend the trip time to 1/2 second.  Consult page 54 of the Zephyr Xtra manual for details on how to do this. 

Cheers,

Niel

[BobB]

Hi Guys,

Thank you Niel for your help and thank you BigEd for the suggestion that I should contact Digitrax direct, this I will do.

Thank goodness for Forums, Facebook, Twitter, Hello Peter etc. and of course the consumer protection act !

[Freightcars]

Hi Bob,

No worries.  I'm curious as to why its not working, hence my interest.  At this point I still think that the trip time on the DCS51 needs setting.

If write to Digitrax Tech Support, be sure to give as much detail as.  The more info given, the more chance they have of helping you.  From my past experience Tech Support doesn't always get the answers write either.  You may need to go back and forth a couple of time to get the right help.

Bob and myself have also exchanged some emails off forum.  We'll be meeting up over the weekend to see if we can figure out whats going on.  I'll report back to the forum afterwards.

Cheers,

Niel

[BobB]

Mr Burkhardt today offered a refund !!!!!!!!!!!!!!!!!!

In the mean time; Mr Niel Wilson (Freightcars) was kind enough to do some testing with my Zephyr and my locomotives. He came to the conclusion that the Zephyr needed to be set so that there was a longer time for it to re-act to a sensed short so that the AR-1 could trip before the Zephyr stopped everything. Niel set the Zephyr for me and I retrieved the AR-1, re-connected it and hey presto everything worked like a charm.

Thank you very much Niel.

Also, thanks are due to Colin Tanner-Tremaine who performed some testing on behalf of Mr Burkhardt.

I have asked Mr Burkhardt to inform Digitrax of the problem and the successful solution that was adopted with the suggestion that their instructions either include or reference potential problems and their corrections to those problems. I do not know if this will happen. On the one hand, all's well that ends well but did it need to be this difficult ?

[capeklr]

Glad that the problem was sorted out. 

[Freightcars]

@Bob

No worries at all.  Glad we could get it sorted out.


Bob and myself got together yesterday morning.  We did some quick testing of his two locos and Zephyr.  Using a RRampMeter we determined that the current draw of his locos.  The Class 20 was pulling approximately 140 mA and the Class 24 was pulling approximately half of that (70 mA).  Both of these locos draw very little current.

We then wired an AR-1 from my layout into the test track, which consisted of 3 pieces of isolated track.  The one on the left was wired normally, the middle one was feed from the AR-1 and the right hand track was wired so that it was reversed from the left hand one.  This gave us a quick and dirty simulation of a reverse loop section.

We then tried to run a loco from one end of the test track to the other end across the auto reverse section.  As expected the Zephyr shut down as soon as the loco hit the reversing section. Once the loco was removed the track power came back up.  Bridging the gaps in the reverse loop with a screw driver on one rail only also caused the Zephyr to trip.

We then set the booster short circuit shutdown time from 1/8th to 1/2 second.  This is done by setting Option Switch 18 on the Zephyr to "c".  Again we tried to run a loco from one end of the test track to the other.  This time the loco tripped the AR-1 correctly when it crossed the auto reverse section.  We repeated the test several times and it worked each time.

In conclusion:  There was a race on between the Zephyr and the AR-1 to see who would detect the short first.  The Zephyr was always winning thus not allowing the AR-1 to do its job.  By slowing down the Zephyr's timing the AR-1 detects the short first and then can do its job properly.

Cheers,

Niel

[BobB]

Hi Niel

An unfortunate postscript to this whole affair :

I was in the process of converting to a dpdt switch before we sorted the AR-1/Zephyr out. This involved removing the under-board peco point motor and substituting a surface mounted one so that I could use Peco's switch. The peco system needs the carrying baseplate to be screwed down. Having started to fit a new motor, I was going to carry on but the screw driver slipped and now I have to replace the whole point and motor assembly. Grrrrrrrr. I can't blame anybody but myself and that makes it more annoying...... Anyway, now I'll go back to putting the motor underneath because I don't need the switch anymore.

Happy days?

Cheers

Bob

[BigEd]

Bob and others using Peco point motors - there's help on the horizon.

You all know how finicky these point motors can be? Fear no more. KevinC, a member here designed and build a fully adjustable base plate mount for Peco point motors! I sold a few here in Cape Town for him over the years.

But now the Cape Townians don't have enough money to buy them and use their fingers to throw points...

[Freightcars]

@Bob - That's no fun.  Unfortunately these things do happen.

@Ed - Hmmm, good to know.  I may need to talk to him about these.

Cheers,

Niel