Abstract: A noise determination device is provided that determines the presence of noise on an input signal with a constant value that is output from an external device. The noise determination device includes a sampling unit that performs three samplings on the input signal, a sampling-interval setting unit that sets an interval between a first one and a second one of the samplings to have a value that is different from an integral multiple of the period of the periodic noise, and sets an interval between the second one and a third one of the samplings to be equal to or larger than an interval that is large enough to fully attenuate the periodic noise, and a noise determination unit that determines that the noise is not superimposed on the input signal only when all values acquired by the first, second, and third samplings match one another.

Abstract: A terminal block includes a top surface formed to be flat, a concave portion formed on the top surface, and a plurality of wiring connecting holes arranged in the concave portion. Wiring display parts corresponding to the wiring connecting holes are arranged on the top surface. The concave portion is arranged in plural for each wiring group. A buttonhole is arranged adjacent to the wiring connecting hole and an opening/closing button for opening and closing a wiring connection fitting located on a bottom part of the wiring connecting hole is accommodated in the buttonhole. The concave portion is a belt-shaped groove.

Abstract: A noise analysis apparatus has a plurality of digital filters and a noise analysis unit. The plurality of digital filters have mutually different filtering characteristics and filter a same input signal to output a plurality of output signals, respectively. The noise analysis unit detects presence or absence of a noise in the input signal, based on the plurality of output signals. More specifically, the noise analysis unit detects the presence or absence of the noise in the input signal, based on whether or not values of the plurality of output signals coincide with each other.

Abstract: A noise determination device is provided that determines the presence of noise on an input signal with a constant value that is output from an external device. The noise determination device includes a sampling unit that performs three samplings on the input signal, a sampling-interval setting unit that sets an interval between a first one and a second one of the samplings to have a value that is different from an integral multiple of the period of the periodic noise, and sets an interval between the second one and a third one of the samplings to be equal to or larger than an interval that is large enough to fully attenuate the periodic noise, and a noise determination unit that determines that the noise is not superimposed on the input signal only when all values acquired by the first, second, and third samplings match one another.

Abstract: A terminal block includes a top surface formed to be flat, a concave portion formed on the top surface, and a plurality of wiring connecting holes arranged in the concave portion. Wiring display parts corresponding to the wiring connecting holes are arranged on the top surface. The concave portion is arranged in plural for each wiring group. A buttonhole is arranged adjacent to the wiring connecting hole and an opening/closing button for opening and closing a wiring connection fitting located on a bottom part of the wiring connecting hole is accommodated in the buttonhole. The concave portion is a belt-shaped groove.