An apparatus and method for selecting a ground capacitor that is connected between a ground of a circuit board included in a battery pack and a vehicle chassis. The apparatus includes a checking module configured to check a ground location on the circuit board; a selecting module configured to select a reference location on the circuit board, based on the ground location checked by the checking module; a calculating module configured to calculate a distance from the reference location selected by the selecting module to a nearest ground location as a reference distance; a computing module configured to compute a reference frequency by using the reference distance calculated by the calculating module; and a choosing module configured to choose a recommended capacitor, based on the reference frequency computed by the computing module.

An apparatus and method for selecting a ground capacitor that is connected between a ground of a circuit board included in a battery pack and a vehicle chassis. The apparatus includes a checking module configured to check a ground location on the circuit board; a selecting module configured to select a reference location on the circuit board, based on the ground location checked by the checking module; a calculating module configured to calculate a distance from the reference location selected by the selecting module to a nearest ground location as a reference distance; a computing module configured to compute a reference frequency by using the reference distance calculated by the calculating module; and a choosing module configured to choose a recommended capacitor, based on the reference frequency computed by the computing module.

A detection device for use with a master device is provided. The detection device includes an electric power source that is intermittently driven to generate electric power, a detector switched between a number of states by occurrence of a predetermined event or a predetermined state, an electric power accumulator that is charged or discharged by switching the state of the detector, and a controller powered by the electric power source. The controller is configured to determine the state of the detector and notify the master device of detection information corresponding to the state of the detector. Activation of the controller powered by the electric power source is followed by acknowledgment of the state of the detector by the controller based on a state of the electric power accumulator.

A control signal protection device protects a current-receiving field device from an undesirable interruption in a control signal provided to the field device. The control signal protection device includes a first terminal to connect the signal protection device to a control system and a second terminal that connects the control signal protection device to a field device. The control signal device further includes a power storing element for temporary accumulation of electric energy and a switching circuit for controlling operational mode of the signal protection device. Electric energy is stored in the power storing element in a first operational mode. Electric energy stored in the power storing element is supplied to a positive terminal in the second terminal pair in a second operational mode.