Type A1, A2 and A3 cables serve fixed railway signalling wiring in relay rooms, signal boxes and equipment locations. All three use class 2 tinned copper with crosslinked LSZH insulation. A1 is an unsheathed single core, A2 adds an LSZH sheath to a single core, and A3 provides an LSZH-sheathed multicore construction. The choice depends on the wiring arrangement and the protection provided by the enclosure or route.
NR/PS/SIG/00005(formerly RT/E/PS/00005)
Electrical Characteristics at 20℃Conductors: Tinned stranded copper, class 2 according to IEC 60228 & BS 6360.
Insulation: LSZH crosslinked.
Core Wrapping: Plastic tape(s) with overlapping.
Sheath: LSZH (for types A2 & A3 only).
| Nominal Conductor Cross Section | mm | 0.75 | 1.15 |
| Maximum Conductor DC Resistance | Ω/km | 24.8 | 17.3 |
| Voltage Rating | KV | 0.65/1.1 | |
| Nominal Insulation Thickness | mm | 0.85 | 0.85 |
Minimum Bending Radius: 6×OD (static); 15×OD (dynamic)
Temperature Range:-25℃ to +85℃ (during operation); -10℃ to +85℃ (during installation)
| Cable Code | No. of cores& Nominal Conductor Cross Sectional Area No.×mm | No. & Nominal Diameter of Strands No/mm | Nominal Sheath Thickness mm | Overall Diameter Min/Max mm | Nominal Weight kg/km |
|---|---|---|---|---|---|
| Type A1(without sheath) | |||||
| BRAIL A1-H-1G0.75(BL) | 1x0.75(blue) | 7/0.37 | - | 2.7/3.2 | 16 |
| BRAIL A1-H-1G0.75(BR) | 1x0.75(brown) | 7/0.37 | - | 2.7/3.2 | 16 |
| BRAIL A1-H-1G0.75(RD) | 1x0.75(red) | 7/0.37 | - | 2.7/3.2 | 16 |
| BRAIL A1-H-1G0.75(OR) | 1x0.75(orange) | 7/0.37 | - | 2.7/3.2 | 16 |
| BRAIL A1-H-1G0.75(GR) | 1x0.75(green) | 7/0.37 | - | 2.7/3.2 | 16 |
| BRAIL A1-H-1G0.75(VI) | 1x0.75(violet) | 7/0.37 | - | 2.7/3.2 | 16 |
| BRAIL A1-H-1G0.75 | 1x0.75(black) | 7/0.37 | - | 2.7/3.2 | 16 |
| BRAIL A1-H-1G1.15 | 1x1.15(black) | 16/0.30 | - | 2.9/3.6 | 21 |
| Type A2(with sheath) | |||||
| BRAIL A2-3GH-1G0.75 | 1x0.75 | 7/0.37 | 0.7 | 4.0/5.0 | 30 |
| BRAIL A2-3GH-1G1.15 | 1x1.15 | 16/0.30 | 0.7 | 4.3/5.3 | 35 |
| Type A3(with sheath) | |||||
| BRAIL A3-3GH-2G0.75 | 2x0.75 | 7/0.37 | 0.9 | 6.7/8.8 | 67 |
| BRAIL A3-3GH-4G0.75 | 4x0.75 | 7/0.37 | 1.0 | 8.0/10.4 | 108 |
| BRAIL A3-3GH-6G0.75 | 6x0.75 | 7/0.37 | 1.1 | 9.7/12.5 | 160 |
| BRAIL A3-3GH-10G0.75 | 10x0.75 | 7/0.37 | 1.2 | 12.6/16.1 | 259 |
| BRAIL A3-3GH-14G0.75 | 14x0.75 | 7/0.37 | 1.3 | 13.8/17.7 | 495 |
| BRAIL A3-3GH-36G0.75 | 36x0.75 | 7/0.37 | 1.6 | 21.6/26.9 | 752 |
| BRAIL A3-3GH-48G0.75 | 48x0.75 | 7/0.37 | 1.6 | 24.3/30.7 | 963 |
Three constructions distinguish unsheathed single-core, sheathed single-core and multicore wiring.
A1 and A2 sizes include 0.75 and 1.15 mm²; the A3 table lists 0.75 mm² cores.
Separate dimension rows support terminal, conduit and cable-entry selection.
Start with the wiring schedule: type, conductor size, core count and identification colour. Use the actual cable diameter when planning entries and bends. The listed radii are 6 times overall diameter for static installation and 15 times during handling. Include route protection and required railway acceptance documents with the enquiry.
Type B1 & B2 Railway Signalling Cable, EPR Insulation and HDPCP Sheath
Type C1 & C2 Railway Signalling Tail Cable, 2.5 mm² Class 5 Copper
Which Type A cable has no outer sheath?
A1 is the unsheathed version. A2 and A3 have an LSZH outer sheath.
How do A2 and A3 differ?
A2 is a sheathed single core; A3 is the multicore construction.
Which conductor sizes are available?
A1 and A2 are listed in 0.75 and 1.15 mm². A3 is listed with 0.75 mm² cores in the listed core counts.
Is LSZH a circuit-integrity rating?
LSZH describes smoke and halogen characteristics. A requirement to maintain a circuit during fire needs its own specified test and supporting evidence.
What information helps identify the right order code?
Provide A1, A2 or A3, conductor size, number of cores, identification requirements and the required lengths.
