BS 88-2:2007 pdf free.Low-voltage fuses — Supplementary requirementsfor fuses for use by authorized persons (fuses mainly for industrialapplication)—Examples of standardized systems of fuses A to I.
BS 88-2 The following additional requirements apply to fuses with fuse-links having boltedconnections. Such fuses have rated currents up to and including 1 250 A and rated voltagesup to and including 690 V a.c.and up to and including 500 V d.c.
The following characteristics of the fuses are specified in addition to the lEC 60269-1:minimum rated breaking capacities;
The maximum values of power dissipation of fuse-links are given in Figure 501.
The values of rated acceptable power dissipation of fuse-holders at rated current when testedin accordance with 8.3.1 are given in Figure 503.
Limits of time-current characteristics
Time-current characteristics, time-current zones and overload curves
ln addition to the limits of pre-arcing time given by the gates and the conventional times andcurrents，the time-current zones，excluding manufacturing tolerances, are given in Figures504 and 505.The tolerance on time-current characteristics shall not deviate by more than+10 % in terms of current.
Conventional times and currents The conventional times and currents,in addition to the values of lEC 60269-1, are given inTable 501.The requirements of lEC 60269-1 apply and in addition fuse-links shall operate without themelting of the fine fuse wire and without mechanical damage to the rig.
Verification of resistance to heat Fuse-holders fitted with fuse-links having the maximum power dissipation corresponding tothe acceptable power dissipation of the fuse-holder shall be cyclically loaded as pre-treatment. The pre-treatment is specified in 8.4.3.2 of lEC 60269-1.After cooling to normaltemperature, the breaking capacity shall be tested at l in accordance with 8.5.
Fuse-links containing organic material in the body or filler shall be subjected to the same testas described above.These fuse-links shall interrupt the test currents l and ls.
Verification of non-deterioration of contacts Subclause 8.10 of IEC 60269-1 applies.
Arrangement of the fuse Subclause 8.10.1 of IEC 60269-1 applies with the following addition.
The dummy fuse-links shall have dimensions that comply with Figure 501 for those referencesthat are accommodated in the standardized fuse-holders in Figure 503.
The power dissipation of the dummy fuse-links shall be the rated acceptable power dissipationof the fuse-holders given in Figure 503 when tested in the standardized power dissipation testrig given in Figure 506.BS 88-2 pdf download.