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Journal of electricity, power, and gas . ed, closingcontact E and F giving local trouble alarm onthe trouble buzzer and operating the telephone troublealarm T sending trouble alarm to the trouble de-partment. For the operation of this system, two duplicatestorage batteries of 12 cells each are employed, con-nected as shown at Bl and B2. through the doublethrow switches SI and S2 so arranged that while one battery is charging, the other battery is supplyingcurrent to the system. The local trouble buzzer is provided with a sep-arate battery B3 consisting of two dry cells and thetrouble alarm T h
Journal of electricity, power, and gas . ed, closingcontact E and F giving local trouble alarm onthe trouble buzzer and operating the telephone troublealarm T sending trouble alarm to the trouble de-partment. For the operation of this system, two duplicatestorage batteries of 12 cells each are employed, con-nected as shown at Bl and B2. through the doublethrow switches SI and S2 so arranged that while one battery is charging, the other battery is supplyingcurrent to the system. The local trouble buzzer is provided with a sep-arate battery B3 consisting of two dry cells and thetrouble alarm T has a separate battery B4 of 4dry cells. All of the batteries are tested daily by theoperation of test button P4 and P5 described For testing one side of P4 and P 5 is groundedat G2. This ground is made at a different locationthan at G3, then should the ground connection ofrelay R10 be broken it would be discovered when atest is made. Operating push button P4, tests one-half of the main battery and contacts of ground relay. Factory Panel Equipment. R10. Operating push button P5 tests the other halfof main battery and also relay R10 and batteries B3and B4. Operating P4 and P5 together shunts thebettery de-energizing relays R 5 and R6, thereby test-ing relay contacts and trouble alarm signals. In addition to the above tests, the alarm companyis required to have an inspector inspect all risks, onceeach month, testing for grounds, opens, etc., and bothsides of each and every circuit is opened to see thatthe relay Rll controlling the trouble box T willact on an open circuit. Both sides of each circuit are also grounded totest all contacts and see that each part of the systemis in readiness to perform its functions. This system has been in operation in the cityof Portland, Oregon, for one year and in that timehas received over its lines 14 fire alarms, three trou-ble alarms, no false alarms and no failures. Thesystem in each risk is inspected and approved bythe Underwri
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Keywords: ., bookauth, bookcentury1800, bookdecade1890, booksubjectelectricity