British Standard BS6387 covers the performance requirements and test methods for cables required to maintain circuit integrity under fire conditions, It has been developed to assist installation designers with their assessment of the fire performance characteristics of various types of cables and their selection for specific applications. In particular, it covers the cables' ability to maintain circuit integrity against set time and temperature parameters.
BS6387 covers fire resistant cables with a voltage rating of 300/500V and 450/750V. It also covers mineral-insulated cables manufactured in accordance with BS6207.
BS6387 Cable categories
| | Resistance to fire alone |
| Category A | 650oC for 3 hours |
| Category B | 750oC for 3 hours |
| Category C | 950oC for 3 hours |
| Category D | 950oC for 20 minutes (short duration) |
| | Resistance to fire with water (W) |
| Category X | 650oC for 3 hours |
| Category Y | 750oC for 3 hours |
| Category Z | 950oC for 3 hours |
For example, a cable meeting the requirements in terms of their ability to maintain circuit integrity for 3 hours at 950oC and also for 3 hours at 650oC when exposed to fire and water would be referred to as CWX.
Other tests covered under BS6387 include voltage tests on completed cables, tests for bending characteristics, tests for resistance to impact at ambient temperature, and tests for fire resistance characteristics.
Eland Cables is a leading supplier of cables designed to maintain circuit integrity under fire conditions, inclu
ding our Firetec cables and a comprehensive range of mineral insulated copper cable manufactured in accordance with BS6387.
CONDUCTORS
| NOMINAL CROSS SECTIONAL AREA mm² | MAXIMUM RESISTANCE OF CONDUCTOR AT 20ºC ohms/km |
| 1 | 18.1 |
| 1.5 | 12.1 |
| 2.5 | 7.41 |
| 4 | 4.61 |
ELECTRICAL CHARACTERISTICS
Current Carrying Capacity
| NO. OF CORES | NOMINAL CROSS SECTIONAL AREA mm² | SINGLE PHASE AC OR DC Amps | THREE PHASE AC Amps |
| 2 | 1 | 17 | - |
| 2 | 1.5 | 21 | - |
| 2 | 2.5 | 28 | - |
| 2 | 4 | 36 | - |
| 3 | 1 | - | 14 |
| 3 | 1.5 | - | 17 |
| 3 | 2.5 | - | 23 |
| 4 | 1 | - | 14 |
| 4 | 1.5 | - | 17 |
| 4 | 2.5 | - | 23 |
| 7 | 1.5 | 12 | - |
| 7 | 2.5 | 16 | - |
Voltage Drop
| NO. OF CORES | NOMINAL CROSS SECTIONAL AREA mm² | SINGLE PHASE AC OR DC mV/A/M | THREE PHASE AC mV/A/M |
| 2 | 1 | 42 | - |
| 2 | 1.5 | 28 | - |
| 2 | 2.5 | 17 | - |
| 2 | 4 | 10 | - |
| 3 | 1 | - | 36 |
| 3 | 1.5 | - | 24 |
| 3 | 2.5 | - | 14 |
| 4 | 1 | - | 36 |
| 4 | 1.5 | - | 24 |
| 4 | 2.5 | - | 14 |
| 7 | 1.5 | 28 | - |
| 7 | 2.5 | 17 | - |
* Method of cable support should withstand a similar temperature and donation to that of the cable.
