Lenz problem

I've got an old hornby with the old style worm drive running ok on Lenz DCC. Have you checked the connections, I got the red light to go out when I shorted the power?

In the bit below you say that you programmed the chip, but you got an E02 so how did you program it? The ID should be set-up for 3.

I got an E02 when I used a Digitrax chip with my Lenz, I found that I had to use a different programming mode to get the information on the chip, try CV or Register, it's in the manual how to do it, Direct mode sends all the data at once and th chip can't cope, or something like tat, where as CV or Register sends each packet at a time in a more sedate manner.

Also get the controller as the power supply and hook them up to a simple piece of track, then get a non-DCC train and put in on the track. Select train ID 0 and you should be able to drive the non-DCC train, this way you can prove the Power Supply and the Controller.

Let us know what happens...

Dave M

I had a similar thing with a Lenz LE0511A on a Lenz compact system. For some reason, after fitting, the chip seemed to go faulty. When I checked the address on the programming track, I'd get an E02. I thought this was faulty and I swapped it for a new one. At the time, I thought that a hidden capacitor across the motor brushes and some inductors (chokes) installed in series with the motor contributed to the problem. These need to be removed.

When I installed the new chip, I noticed that if I removed the motor and tried to check the address, I'd get an E02. With the motor replaced in the chassis, the decoder would show its address properly. So an E02 does not mean that the decoder is faulty.

I seem to remember reading somewhere that you could not just connect the red and black wires directly to the programming track (in order to check the decoder) because there is not enough load on the decoder's circuits to allow it to function correctly.

Perhaps there are bad connections in your loco's motor or pickup circuits?

Mike

Thanks David & Mike. The story so far:

I've c>When I installed the new chip, I noticed that if I removed the motor and

That's interesting. The Hornby J38 has an LC circuit which I will try removing; I also have a Hornby tender-drive A4 but that's my son's pride & joy so I want to get it right before messing with that ;-)

The decoder seems to communicate up to a point, which agrees with what Mike said. Out with the soldering iron again...

Guy === May contain traces of irony. Contents liable to settle after posting.

Having removed it, the loco will now run backwards but not forwards! Programming also seems erratic. I'm going to desolder the pickups entirely, clean them and re-make the contacts, as intermittent stupidity has the feel of a dry joint about it.

Ooooh! It's exciting! I might actually be able to get the bleeder going soon. Failing that I'll convert the whole sodding layout to gas.

Guy === May contain traces of irony. Contents liable to settle after posting.

The story so far: I found that the transformer had died (second one - no idea what's going on), and was using a generic 16V transformer. This kept cutting out, so I sourced a 15V 7VA transformer from my local electronics shop, with suitable overcurrent protection, and hey, presto! things are starting to come together.

The intermittent short on the Hornby A4 finally became permanent so I could trace it. It now runs flawlessly, apart form lack of traction which I eventually traced to the front (tender) driving wheel not being driven - the cog was incorrectly aligned. I inserted an oiled paper psacer behind it and it was Much Better.

The only thing is that now my J83 won't run. It reads and writes fine on the programming track, motor pulses as it does so (in what I assume is the usual way), but when you issue the command to go forth, it sits there without even buzzing the motor. Hmmm...

Guy === May contain traces of irony. Contents liable to settle after posting.

If that's really a 7VA transformer its seriously underpowered for a DCC system, it is unlikely that your DCC system protection circuits will work with it. You should get a 50VA transformer at least, 100VA if you want some headroom for expansion.

Check that all the other CVs are at factory defaults, especially the maximum voltage.

Keith

Make friends in the hobby. Visit Garratt photos for the big steam lovers.

If the loco will not run on the programming track... Not sure whether you know this or not, but the programming track is designed in such a way that motor operation is not possible. I've seen a diagram somewhere showing that the programming track output is the same as a regular DCC output, but with a fairly high value series resistor. The purpose of this is to limit short circuit fault current so that your decoder is not damaged. So to check your motor, you'll have to make sure there are no shorts first, then check the decoder address can be read, then put it on the normal running track.

If the loco will not run on the normal track... Can you measure the *decoder* output voltage in order to eliminate it and the DCC system from the cause of fault? On my lenz LE0511A, I can check for DC volts using a multimeter connected across the orange and grey terminals. I can see a different voltage corresponding to different speed settings.

Hope this helps.

Mike

Zero volts. Also nothing on the accessory terminals (e.g. lights).

Guy === May contain traces of irony. Contents liable to settle after posting.

So on the programming track you can read/write the address, but on the programming track or on the running track you get no output from functions or motor output?

Are you testing close to the decoder terminals? (on the PCB would be best)

I think it's unusual to be able to program the address of a decoder without the decoder outputs being connected to anything - as Rob said. Also, as Keith said in this thread - check the CVs are at there factory defaults. Alternatively, there could be direct shorts across your outputs in the loco circuits, which would cause zero volts to appear across orange-grey, white-blue and yellow-blue teminals (on my LE0511A).

I had trouble installing my first decoder, and I had to unsolder the decoder and do a resistance check across the above connections on the loco. You should see in the region of 50-100ohms for a lightbulb and maybe 10 ohms for the motor? (I don't have exact figures) but they should each be greater than

Good luck. And if all else fails, remember to open the window before throwing anything through it : )

Mike.

Correct. The programming track is an isolated siding with a DPDT switch - I am trying to run in the context of main, and program in the context of the prog track. Programming is working flawlessly, and the loco moves slightly as it is programmed, plus if I connect 12V direct to the motor terminals (having first unplugged the decoder) the motor spins.

At the gold tags adjacent to the connector, yes.

Yup, I've got that point. There is another loco working fine. I'm not going to swap decoders because if the loco is burning out the decoders we'll end up with no running locos, so I think I'll buy another decoder.

I Reset the decoder and also checked the CVs manually.

Possible, I suppose, I'll check that. I wish I had an oscilloscope!

Sure. Everything seems OK, and the motor will run given 12V DC, so I am a bit puzzled.

Oh - thanks for the help, folks, and happy new one!

Guy === May contain traces of irony. Contents liable to settle after posting.