| 摘要 |
The present invention proposes a control device and control method for a fire alarm system, the control device and control method being capable of monitoring an on-line impedance or inter-wire impedance of field wires. The device is connected to a line, with a capacitive element being terminally connected at a far end of the line. The method comprises: sampling at least three output voltages (V 1 , V 2 , V 3 ) of the monitoring power supply at at least three different time points (t 1 , t 2 , t 3 ), respectively, wherein the at least three time points are all before the capacitive element reaches saturation, and the time points include at least three time points which satisfy: t 2 = nt 1 , t 3 = (2n-1)t 1 , where n is an integer greater than 1; and based on the at least three output voltages (V 1 , V 2 , V 3 ), calculating an on-line impedance (Rc) or inter-wire impedance (Rs) of the line. |
