| 摘要 |
PURPOSE:To improve a reliability of a system under an abnormal condition by a method wherein a plurality of cooling fans are divided into an upper stage group and a lower stage group and when a special signal is generated in response to a trouble of each of the cooling fans in each of the groups, the system is turned off. CONSTITUTION:When a plurality of shells 3 installed in an electrical equipment 1 are cooled by air, a plurality of cooling fans 2a to 2f are divided into two groups of upper and lower ones in their lateral line units. In turn, a cooling fan abnormal state generating circuit is provided for each of the cooling fans. The abnormal signal is informed to OR circuits 4a and 4b in a power supply control part 4 divided by upper and lower stages in an electrical equipment 1. Outputs of both OR circuits 4a and 4b are input terminals of each of AND circuits 4c, resulting in that if the AND circuit 4c outputs '1', a power supply part 5 is turned OFF and then the system is also turned off. |
