NEM standards are the standards for model railroads issued by the MOROP. NEM stands for Normen Europäischer Modellbahnen (German) or Normes Européennes de Modélisme (French), both of which translates to European standards for model railroads.
The NEM standards are defined and maintained by the Technical Commission of the MOROP in collaboration with model railroad manufacturers.
The NEM standards define the model railroad scales and guide manufacturers in creating compatible products and assist modellers in constructing model railroad layouts that operate reliably. The standards cover areas like suggested gradients, turn radiuses, wheel profiles, coupling designs and Digital Command Control and are mostly scale specific. A fundamental principle in NEM standards are compromises in the exact scale reduction ratio in order to favor operational reliability of model railroad systems. An example for this are wheel flanges which tend to be proportionally wider in smaller scales to ensure a reliable operation.
The NEM standards cover aeas similar to the standards and recommended practices defined by the NMRA in North America, but the two standards are not universally interchangeable. In recent years, MOROP and NMRA have been working more closely together to establish common standards for developments such as Digital Command Control. European model railroad manufacturers generally follow the NEM standards, while North American manufacturers generally follow NMRA standards instead.
- MOROP - MOROP, the association defining and maintaining the NEM standards
(Some of this page's content was taken from the NEM article in Wikipedia)