Fault Levels for CL Fusing of Transformers
Fault Levels for CL Fusing of Transformers
(OP)
We would be interested in knowing what most utilities use as the fault current level at which they install current limiting fuses on 3-phase pad-mounted transformers (to minimize explosion). We realize that: (1) bayonet expulsion fuses have a 3500 amp limit (so we may use fuses in air or a VFI); (2) most CL fuses are not large enough for very large transformers, (3) CL fuses my need to be paralleled for large transformers, (4); and smaller transformer may be more susceptible to exploding; but (5) fault currents might be higher where larger transformers are used because they require a stiffer system. (Base response on. 7.2/12.5 kV grd Y systems). Thank you.





