Wednesday, June 10th, 2009

FREMO

This idea basically allows lots of different people to create model railway modules and to be able to link them together in all different arrangements to create huge layouts. The standards for the system need to specify how the connections between the modules are to be made so that everyone’s modules will be compatible.

There are several different standards in use around the world that are incompatible with one another. The Australian Model Railway Associaltion recently released a standard for Australian use.

I wasn’t involved in the development of the Australian standard but as a member of the Federal Committee of management of the Association I did get to vote to adopt that as the standard. The AMRA standard is compatible with some of the overseas systems but obviously since those systems are themselves incompatible with one another it wasn’t possible to be compatible with all of them.

There are three main aspects to the standard where I believe that the right decision was made.

  • There are two methods of setting up tracks to cross from one module to another. One method involves having the track on the modules end a short distance back from the edge and inseerting a short bridging track while the other involves fixing the track down securely right at the end of the board. From the experience I have had with using these two methods on different model railways I have built the second of these methods is so superior to the first that I’d never again consider using bridging track between modules for any reason. The AMRA standards committee made the same decision and the AMRA standard uses the sensible approach of track right to the edge. That immediately makes the AMRA standard incompatible with those poorly thought out standards that use bridging track.
  • The second aspect I wish to mention is the method by which power is passed the length of the modules. Some of the standards already in use have demonstrated that when you have a huge layout that the methods that they have selected for connecting power through the layout has issues with distance. This is well known from other electronic fields such as computers where for example different categories of network cables have different maximum distances specified for their use. The longest distance for which such network cables that use wire rather than fibre optics is category five cable which is good up to 100 metres. The AMRA standard has adopted this for some of the through wiring for modules to support layout sizes of up to 100 metres where some of the overseas systems use other systems which are only good to 30 metres.
  • The third issue that I want to mention is plugs used for connecting the through wiring. Now here the choices are less obvious as to which is superior to what however there are some of the existing overseas standards that are compatible with the above choices that the AMRA standards committee made and so it makes sense to select the same plugs as those standards use so as to be as compatible as possible with the existing overseas standards. This AMRA has also done.

Sp basically AMRA has set standards that are the Australian equivalent to the best of the overseas standards that have already been developed but which is incompatible with inferior systems. Since the standard can’t be compatible with all of the different incompatible standards it makes sense to be compatible with the ones that got the most obvious things right.

Be Sociable, Share!

Tags: ,

Comments are closed.