×
单选题
341. When the smoke control relay R648 energizes, it supplies 28v dc to energize the supply system control interrupt relay R645
A
When the smoke control relay R648 is powered, it gives 28v dc to activate the supply system control interrupt relay R645.
B
As the smoke control relay R648 is connected, 28v dc is supplied to the supply system control interrupt relay R645.
C
When the smoke control relay R648 has power, it needs 28v dc to start the supply system control interrupt relay R645.
答案解析
正确答案：A
相关题目
单选题
3022. The unit pressurizes and filters the oil
单选题
3021. Engine fire detection system is system of dual loop
单选题
3020. 安全扫描器检测金属物体。
单选题
3019. The system test, which is self-contained and may duplicate other tests, contains all adjustments and tolerances to maintain systems or units at maximum efficiency
单选题
3018. Release the pressure from the hydraulic system
单选题
3017. Individual wire identification codes are established to assist in tracing circuitry (Figure 5)
单选题
3016. Make sure that the lock nut touch the springs
单选题
3015. Put the tools in the solvent to make the compound soft
单选题
3014. 用柔软的布将窗户擦亮
单选题
3013. 接通地面电源
