| 摘要 |
<p>PURPOSE:To prevent a cable number required for monitor from being increased even when the number of repeater chassises is increased by connecting one terminal of a contact of a gas alarm sensor fitted to n-set of repeater cases to a 1st cable and connecting other terminal to a connection part corresponding to connection parts of resistors provided side by side inserted to a 2nd cable respectively. CONSTITUTION:One terminal of contacts 311, 321, 331, 341 of a gas alarm sensor is connected to a 1st cable 4 connecting one terminal of a digital resistance meter of a terminal station A and one terminal of a digital resistance meter 72 of a terminal station B. Moreover, one terminal of the contact 311 of the gas alarm sensor is con nected to the other terminal of the digital resistance meter 62 of the terminal station A via a resistor R0 and connected to the other terminal of the contact 321 of the adjacent gas alarm sensor via a resistor R1. When, for example, a computer 61 of the terminal station A sends a measurement command to the digital resistance meter 62, the digital resistance meter measures the resistance between the 1st cable and the 2nd cable. When the read resistance is larger than a built-in reference value 4r, it is discriminated that the gasypressure is normal, but if the resistance is smaller, a faulty point is located to display the number of a faulty repeater and energizes a buzzer of the alarm sensor.</p> |
