Model Railway Forum

My friend has a massive N gauge European layout that is controlled by iTrain and uses a Roco Z21. He recently invested in a Roco Z21 booster as his layout is very large indeed. His problem is this - the whole system does not always switch on at all– absolutely nothing although the power is there….and he doesn’t know why. Sometimes it comes on and the whole layout works fine…and then on another visit, although switched on, absolutely nothing comes on, rendering the whole layout completely powerless. Any suggestions to fix this very frustrating problem would be grateful. Thanks in advance. I am still analog so I am unable to help him. Regards, Richard

I'm also an analogue modeller, so not an expert... but I beleive there are others here that use Z21... they'll probably be able to help more than I...

My first thoughts on this is that there is an intermittent short somewhere in the system or the booster is somehow faulty. Here's what I'd do :-

• Disconnect the z21 and booster from the rails & accessories, and disconnect the booster from the z21. Switch the unit on and check all is ok?

• Connect the z21 to a spare section of track only, power up and check if you can move a loco

• Repeat the above with the booster connected to the z21

That should isolate if there are issues with the Z21 or Booster, if all tests pass you'll need to go to the layout itself and go through all the wiring and connections to make sure they are properly connected, and that there are no shorts. You'll probably also want to disconnect/reconnect accessories in turn to see if the issue is in some way related to them. I'd also go through each point in turn, and power up the z21 with the point in each position incase thats the issue.

Hopefully someone with Z21 experience will be along shortly, but if not... I hope this helps!

Regards,

Steve D.

Thanks very much for your response. I will pass that onto him.

I have both a Z21 and a Z21 dual booster. I use Traincontroller rather than iTrain. When you say the layout does not come on what exactly happens? If both Z21 modules are working normally, then both should have a steady blue indicator light. Any other light - red, or flashing red - then there's a short somewhere. Are there many sound locos? These can cause an inrush of power at start-up.

Many thanks for your reply. There's no power at all anywhere on his very large layout - unable to do anything. He does have lots of Fleischmann and Minitrix locos with lights and sound capability. The fault doesn't seem to be a short circuit as the next time he switches on the main power supply, it might all come on....but sometimes it doesn't. Your point about the sound locos is good. Perhaps he should leave the power for a while to get all around his system (It is a very, VERY large layout, something that you'd expect of a German manufacturer at a major train fair.) Thanks for replying.

The reason behind the implication of a short somewhere, is that most devices like controllers have methods to detect shorts and protect themselves from their effects... hence, if the short is caused by a particular setting of the points for instance... the device won't switch on.