发明名称 |
Disaster prevention monitoring apparatus |
摘要 |
A disaster prevention monitor is disclosed in which the power consumption during a line monitoring process is reduced, and a disconnection or a short circuit of control lines can be detected by using a single switching means. A central station has a monitor command transmitter for transmitting a monitor command signal to initiate monitoring of power and control lines. A terminal or repeater station has circuitry for controlling the connection of control lines between a line monitor and power lines. During normal conditions, the control lines are not connected to the power lines, but become so connected only in response to a command from the central station. A line monitoring command causes generation of a negative voltage which is applied to line monitoring circuitry to actuate such circuitry for monitoring the status of the power and control lines.
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申请公布号 |
US5475363(A) |
申请公布日期 |
1995.12.12 |
申请号 |
US19940212854 |
申请日期 |
1994.03.15 |
申请人 |
HOCHIKI CORPORATION |
发明人 |
SUZUKI, MUNEMASA;KOYAMA, KIYOAKI;SHIMOKAWA, TAKASHI |
分类号 |
G08B25/00;G08B26/00;G08B29/06;(IPC1-7):G08B29/00 |
主分类号 |
G08B25/00 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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