Recommended Practices are only less mandatory than Standards by virtue of their slightly less critical subject matter and/or the fact that deviation for specific reason is permissible.

1. Powering of local tracks, switch machines, building lights, etc., is the responsibility of the individual builder and should be separate from circuits which interface with other modules in a layout.

2. Modular layouts may be easily divided into control blocks for multi-train operations. Blocks will normally be used to control trains on your own module or group of modules. To insert a block, place insulated rail joiners at one end of each bridge track and unplug the connectors at each end of break.

3. Block control of mainlines must be approved by all module participants.

NOTE: Common rail is NOT compatible with NTRAK wiring specifications. Check the S.I.G. for your particular scale for further details.

NOTE: S scale wiring is entirely different. Check NASG module specs for details.


The above diagram is available in two formats to facilitate printing and viewing.
Adobe acrobat version (Acobat Reader required) or 1790x2430 121k landscape GIF
Use #22 to #24 ga solid wire soldered to the outside of rails for connection to track power leads. "Solder terminal Strips" make an easy to trouble shoot connection point. Use as many power feeds per tracks as needed.

NOTE: A single large power supply is used with the many throttles on large layouts. The three tracks MUST NOT have any common connection. DO NOT use "COMMON RAIL" wiring. Gaps must be used on both rails on any crossover tracks. If the three main tracks are part of a yard, it must be possible to isolate them electrically.

Use UL approved heavy duty, multi outlet, extension unit with a grounded (three wire) power cord, 14 ga wire, 15 amp capacity. Use Stanley 1-1/4" Safetycup Hooks #V8482 to retain cord. Unit must be removable to meet safety codes, Wiring is subject to inspection by safety officials at public gatherings. if built in, 110V wiring must meet National Electric Code for Temporary winng, or any stricter local codes.

NOTE: For safety, a GFI (Ground Fault interrupter) circuit breaker is recommended in the 110 line powering a layout.

Page last updated June 26, 2001
Copyright (c) 1995-2001 National Model Railroad Association. All Rights Reserved.

This page is written and maintained by:Roger P. Hensley,
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