Circuit Integrity under Fire Conditions Apparatus
(BS 6387; IEC 60331; EN 50200)
1. Resistance To Fire Alone Testing (as prescribed in BS 6387 Protocol C / IEC 6033111)
The cable in question is mounted horizontally into a chamber, constructed of Zintec, with up to 5 ring clamps. It is then exposed to a 610mm long tube type gas burner.
Electrical continuity is checked throughout a 3 hour exposure to the gas burner set at an appropriate temperature.
2. Resistance to Fire with Water (as prescribed in BS 6387 Protocol W)
The cable is held with a metal support and the assembly is housed in an electrically earthed test frame which is held in a large, watertight, Stainless Steel trough.
The frame is also fitted with gas burners, a water sprinkler head and means to power and test the continuity of the cables.
A 400mm section of the cable in question is exposed to flames at 650°C, produced by a gas burner, for a period of 15 minutes.
The water spray is then switched on, in order to comply with the standard BS 6387 (Protocol W), the cable must maintain electrical integrity whilst both water and flames impinge on the cable for a further 15 minutes.
3. Resistance to Fire with Mechanical Shock (as prescribed in BS 6387 Protocol Z / IEC 60331 parts 1, 2 and 3 / EN 50200)
The cable is mounted on a vertical framework or board made from noncombustible material, depending on the standard.
This vertical framework / board is mounted onto rubber bushes such that it will be hit by a bar which is driven to fall on to the top edge of the framework / board at regular intervals during the test.
The powered cable must maintain electrical continuity when exposed to the flames from the burner and impact from the falling bar.