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Modules built prior to the acceptance of these Standards will be exempt from these Standards. However, if non-conforming modules are to interface with conforming modules, a Transition module will be required to accommodate any difference in trackage, electrical, etc.
| Scale | Height From Floor To Top of Rail | Hand Laid or Commercial Rail Code | Interface Track Clearances H=Horiz V=Vertical |
Track Center Lines from Front of Module | Track Centers Parallel Tracks | Track Setback From End of Module | Center Lines on Curves |
|---|---|---|---|---|---|---|---|
| * denotes change from previous issue. | |||||||
| Zn-3 * | 40" (1016mm) | 60 | H=15/32" (12mm) V=1-19/64" (33mm) | 5" Single (127mm) 6" Second (153mm) | 1" (25mm) | 2-3/16" (55mm) | 1" (25mm) |
| Zn-3 n/a at this time. Figures included for possible future use. | |||||||
| Nn3 | See Note n1 & nA | 60 n2 nB * | H=19/32" (15.1mm) V=1-21/32" (42.1mm) | 2" Single (50.8mm) 8-1/2" Second* (215.9mm) | 1" (25mm) | 2-3/16 nC (55mm)* | 1" (25mm) |
| HOn2 | 40" (1016mm) | 70 n3 | H=3/4" (19mm) V=2-1/8" (54mm) | 6" Single (152.4mm) 7-11/16" Second (192.3mm) | 1-11/16" (42.9mm) * | 4" (101.6mm) | 2" (50.8mm) |
| HOn2-1/2 | 40" (1016mm) | 55 (9mm ga) | H=1-1/32"n4 (26.2mm) V=2-3/16" (55.6mm) | 5" Single (127mm) 6-13/16" Second (169.6mm) | 1-13/16" (46mm) | 2" (50.8mm) | 2" (50.8mm) |
| HOn3 | 40" (1016mm) | 70 n3 | H=1-1/32"n4 (26.2mm) V=2-11/32"(59.5mm) | 5" Single (127mm) 7" Second (177.8mm) | 2" (50.8mm) | 4" (101.6mm) | 2" (50.8mm) |
| Sn2 | 42" (1067mm) | 70 (10.5mm)n5 | H=1-1/8" (28.6mm) V=3-3/16" (81mm) | 6" Single (152.4mm) 8-1/4" Second (209.5mm) | 2-1/4" (57.2mm) | 4" (101.6mm) | 2-7/16" (61.9mm) |
| Sn2-1/2 | 42" (1067mm) | 70 | H=1-1/8" (28.6mm) V=3-3/16" (81mm) | 6" Single (152.4mm) 8-1/4" Second (209.5mm) | 2-1/4" (57.2mm) | 3" (76.2mm) | 2-9/16" (65.1mm) |
| Sn3 | 42" (1067mm) | 70 | H=1-1/8"n4 (28.6mm) V=3-3/16" (81mm) | 6" Single (152.4mm) 8-1/4" Second (209.5mm) | 2-1/4" (57.2mm) | 4" (101.6mm) | 2-9/16" (65.1mm) |
| 0n2 | 43 1/2" (1104.9mm) | 70 | H=1-7/16"n4 (36.5mm) V=4-1/4" (108mm) | 8" Single (203.2mm) 11" Second (279.4mm) | 3" (76.2mm) | 4" (101.6m) | 3-5/16" (84.1mm) |
| 0n2-1/2 | 43 1/2" (1104.9mm) | 100 | H=1-7/8" (47.6mm) V=4-1/4" (108mm) | 5" Single (127mm) | 3" (76.2mm) | 2" (50.8mm) | 3-5/16" (84.1mm) |
| 0n3 | 43 1/2" (1104.9mm) | 83 | H=1-7/8" (47.6mm) V=4-1/4" (108mm) | 8" (203.2mm) | 3-3/4" (95.2mm) | 2" (50.8mm) | 4" (101.6mm) |