H—47

This indicated that the fusing current had been in excess of 2,000 amps with a timedelay less than five seconds and that the preheating current did not exceed 30 per cent, of minimum fusing current of 325 amps —that is, 100 amps. From information received from Municipal Electricity Department the maximum load current for two-monthly period prior to the fire was 173, 171, and 173 amps per phase. As the fire occurred at approximately 3.30 p.m. on a hot, sunny afternoon in the middle of November it can safely be assumed that the lighting and heating load would be low and that the load per phase would be in the vicinity of 100 amps. This means that if there was any fault current it would be of a very low value.

Fig. II. —Length of Interstrand Weld Against Pre-heating Current for 22/.029 Fuse Link with Blowing Current of 1,800 Amps.

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