A fence tester for testing the voltage in an electric fence comprises a handle member and a blade member pivotally coupled to the handle member between an open state extending from the handle member and a closed state partly recessed into the handle member. The handle member defines a hollow interior region, and comprises a printed circuit board having an electronic monitoring circuit therein. An antenna coupled to the electronic monitoring circuit is configured to conduct an electrical current induced therein by an electric field generated by a pulsating voltage in the electric fence when the fence tester is located adjacent the electric fence. A latching element located in the handle member operated by a manually operated operating element in the handle member latches the blade member in the open state and the closed state.

The present invention relates to a transformer relay and a battery voltage measurement system using the same and the transformer relay includes: a transformer transforming voltage of a voltage measurement signal according to a wiring ratio of a first wiring and a second wiring; and a relay transferring voltage of a battery while an operation state is changed to an On state when the transformed voltage of the voltage measurement signal is input and the battery voltage measurement system using the transformer relay, includes: the transformer; and a measurement unit measuring a battery voltage value by receiving the voltage of the battery from the relay.

A door switch inspection device for detecting an abnormal condition of a landing door switch used in an elevator is disclosed. Each of a plurality of landing door switches is disposed on a corresponding landing door at each landing floor for detecting an open/closed state of the landing door. The door switch inspection device includes a plurality of voltage detection units connected to the ground side of their respective landing door switches for detecting a voltage value of their respective landing door switches, and a switch contact monitoring unit for detecting an abnormal condition of a landing door switch, which is carried out by calculating a voltage difference between two adjacent floors and comparing the voltage difference with a threshold voltage.

A power control apparatus according to the present disclosure includes a first interconnection relay and a second interconnection relay configured to interconnect or parallel off an inverter to or from a power grid, a reference potential relay configured to set a neutral phase of an independent operation output system to a reference potential, voltage sensors respectively installed between the first interconnection relay and the inverter and between the first interconnection relay and the power grid, voltage sensors respectively installed between the second interconnection relay and the inverter and between the second interconnection relay and the power grid, and a controller configured to turn the reference potential relay on to set the neutral phase to the reference potential and then to judge whether a state of each interconnection relay is normal on the basis of voltage values measured by the voltage sensors.

A door switch inspection device for detecting an abnormal condition of a landing door switch used in an elevator is disclosed. Each of a plurality of landing door switches is disposed on a corresponding landing door at each landing floor for detecting an open/closed state of the landing door. The door switch inspection device includes a plurality of voltage detection units connected to the ground side of their respective landing door switches for detecting a voltage value of their respective landing door switches, and a switch contact monitoring unit for detecting an abnormal condition of a landing door switch, which is carried out by calculating a voltage difference between two adjacent floors and comparing the voltage difference with a threshold voltage.

The present invention relates to a transformer relay and a battery voltage measurement system using the same and the transformer relay includes: a transformer transforming voltage of a voltage measurement signal according to a wiring ratio of a first wiring and a second wiring; and a relay transferring voltage of a battery while an operation state is changed to an On state when the transformed voltage of the voltage measurement signal is input and the battery voltage measurement system using the transformer relay, includes: the transformer; and a measurement unit measuring a battery voltage value by receiving the voltage of the battery from the relay.