The invention discloses prison perimeter high-
voltage power grid linkage alarm equipment, which structurally comprises a
machine body, a power connection port, a
loudspeaker and a heat dissipation net, wherein the right side of the
machine body and the power connection port are integrally formed, and the periphery of the heat dissipation net is fixedly installed on one side of the
machine body; the machine body comprises a shell, a cable, a selective power-off structure, an
infrared emitter and a sounder. The selective power-off structure is matched with an
electromagnet on the cable, connection is kept through magnetic force resistance of a lower pressing ring under the normal condition, current can normally flow into the machine body to enable alarm equipment to work, and when a high-
voltage power grid is short-circuited, huge current firstly flows through the
electromagnet on the cable to generate huge magnetic force, so that the selective lower pressing ring cannot be pressed and bounced off to disconnect a circuit, meanwhile, the current is further prevented from flowing in through fusing of the burning fuse, and meanwhile, a built-in power supply is started to drive the cableto work. Alarm equipment is prevented from being burnt due to the fact that a large amount of current is injected at the moment of
short circuit. And maintenance is more convenient.