WIRING by John Joyce
For those contemplating some rewiring, the following notes may be of some use. mohm should of course be m(Omega).
Cable Sizes and Railpart Part No's
Current cable types - Polyrad. Can also be ordered from Anixter.
| Railpart cat no | Strands | mm2 | Approx resistance mohm / m (pair of cables) |
| 006/110950 | 37/0.2 | 1.16 | 38 |
| 006/110960 | 37/0.25 | 1.82 | 24 |
| 006/110970 | 37/0.3 | 2.62 | 17 |
| 006/110980 | 37/0.4 | 4.65 | 9.5 |
| 006/110990 | 61/0.4 | 7.67 | 5.7 |
| 006/111000 | 80/0.4 | 10.1 | 4.4 |
| 006/111010 | 126/0.4 | 15.8 | 2.8 |
| 006/111020 | 196/0.4 | 24.6 | 1.8 |
| 006/111030 | 276/0.4 | 34.7 | 1.3 |
| 006/111040 | 396/0.4 | 49.8 | 0.93 |
| 006/111050 | 360/0.5 | 70.7 | 0.62 |
| 006/111060 | 475/0.5 | 93.3 | 0.47 |
| 006/111070 | 608/0.5 | 119 | 0.36 |
| 0006/155020 | 27-core jumper cable | ||
Old cable types
| Strands | mm2 | Replacement | Typical Uses |
| 3/0.036" | 1.97 | 37/0.3 | Some heater circuits |
| 7/0.029" | 2.98 | 37/0.3 | Most control circuits |
| 110/0.0076" | 3.22 | 37/0.3 | A few control circuits - use 37/0.3 |
| 7/0.036" | 4.60 | 37/0.4 | Heater power circuits (motor, glow plug) |
| 7/0.044" | 6.9 | ||
| 7/0.052" | 9.59 | 80/0.4 | Power supplies, lights, train wires 33 and 34 |
| 19/0.52 | 26 | ||
| 163/0.018" | 26.8 | 196/0.4 | Charge sockets |
| 248/0.018" | 40 | ||
| 61/0.044 | 60 | ||
| 416/0.018" | 68.3 | 360/0.5 | Engine start |
| 235/0.029" | 100 | 475/0.5 | Dynamo, main battery |
A note on the use of 7/0.052" for some circuits where it seems excessive. Whilst a smaller cable would be sufficient to carry the required current, the voltage drop becomes unacceptable over lengthy runs.