芝加哥火灾报警系统的电机发电机。
芝加哥，生病了。安装了Gamewell火灾报警系统的情况下，具有闭合电路系统 - 在所有大城市中通常。通过这是指电路，少量电流保持不断流动 - 一个警报盒串联放置，并且街道信号箱的瞬间打开导致火灾报警信号被转动在。为了确保电流供应的绝对可靠性和恒定，储存电池代替重力电池。为了在电池充电时提供供应火灾报警电路的供应，已经放入了一组电动发电机，适用于从C无电压运行。这些电动发电机中的每一个是通过柔性耦合直接连接到适合于适合于特定火灾报警电路的电压的直流电器连接的110伏电机，希望 - 两台机器设置在同一张床上盘子。电动机和发电机都是分流器缠绕的，以这种方式，两台机器的字段直接连接在1个LO压电源电路的电源上。电动机的速度通过其场电路中的可调电阻而变化。发电机的场电路还具有可变电阻。从发电机的电枢连接到火灾报警电路的连接时，电路通过各种街道报警盒耗尽，并通过中央局的继电器返回给电机发生器。 The office apparatus which the relay operates does not concern this article. The double throw switch is for throwing the fire alarm circuit either on the motor generator or on the storage batteries. The duty of the motor generator, when in use, is to maintain on an alarm circuit a current of .04 ampere. The current in the fire alarm circuit can evidently be adjusted in a number of ways by the arrangement shown. The current round the fields of the generator can be varied; the speed of motor can be changed by varying the motor field resistance; or, finally, an adjustable resistance in the fire alarm circuit itself can be used to regulate the amount of current flowing in the fire alarm circuit. Six motor generators have been put in. One of these gives 100 volts for the alarm circuit; two give seventy volts; and three give forty volts. Thus six different circuits are supplied. The motor generators have been in continuous operation since they were pui in. and, except when the storage battery is being “ exercised,” will probably be used most of the time.
At the recent tournament of the New England States Veteran Firemen’s league held at Portland, Me.,the Springfield,Mass., veterans were in fine shape. They mustered 250 men in uniform and won the silver cup for presenting the finest appearance on parade. If they win it again, it becomes their property. They appeared to splendid advantage in the march. Their number and the fact that they drew their engine, instead of having it hauled by horses, was greatly in their favor.
