An apparatus comprises a housing and a plurality of electrical contacts. Each of the plurality of electrical contacts are arranged to sequentially contact a contact device as the contact device moves through the housing. The contact device comprises a first end configured to couple to a bolt, a second end opposite the first end, and a conductive region between a first insulated region and a second insulated region.

A frequency characteristics measurer is disposed in the vicinity of an end of refrigerant piping, the end of which is connected to an outdoor unit, that connects the outdoor unit and an indoor unit of an air conditioner, and measures frequency characteristics of the refrigerant piping. A filter is attached at a position between the outdoor unit and a position where a terminal of the frequency characteristics measurer is connected, so as to wrap the refrigerant piping. A piping length calculator is connected to the frequency characteristics measurer via an interface cable, and acquires, via the interface cable, frequency characteristics measured by means of the frequency characteristics measurer. The piping length calculator extracts a lowest anti-resonant frequency from the acquired frequency characteristics, and calculates the length of the refrigerant piping on the basis of the extracted lowest anti-resonant frequency.

An apparatus comprises a housing and a plurality of electrical contacts. Each of the plurality of electrical contacts are arranged to sequentially contact a contact device as the contact device moves through the housing. The contact device comprises a first end configured to couple to a bolt, a second end opposite the first end, and a conductive region between a first insulated region and a second insulated region.

The invention relates to a method for setting up two sensor systems for monitoring the state of wear of a chain, which method comprises the steps: first positioning of the first sensor system relative to a calibration object, first positioning of the second sensor system relative to the calibration object, carrying out a first signal detection using the first sensor system, carrying out a first signal detection using the second sensor system, wherein the first signal detection using the first sensor system takes place at the same time as the first signal detection of the second sensor system.

The invention relates to a method of determining the elongation of segments of a chain during operation, comprising the following steps: Performing a first detection to determine a position of a first chain component and detecting a first measurement value, performing a second detection to determine a position of a second chain component and detecting a second measurement value, and determining the distance L between the first and the second chain component, wherein the first detection and the second detection are performed simultaneously.

Systems and methods are provided for monitoring properties of a web during a roll-to-roll manufacturing process. The methods may include moving the web past a first roller such that the web contacts the first roller, wherein the first roller includes a first contact strip formed of an electrically conductive material and extends circumferentially about the first roller, applying a voltage to the first contact strip while moving the web past the first roller, such that the voltage conducts through the web to a second contact strip, measuring the voltage received by the second contact strip, determining local resistance values relative to positions of the web based on the difference in the voltage applied to the first contact strip and the voltage received by the second contact strip, and determining at least one property of the web relative to the positions of the web based on the local resistance values.

A cable length measurement device, configured to: be connected a winding wheel and measure an extension or retraction length of a cable on the winding wheel, which includes a fixed shell, a rotating shell and a control panel. The rotating shell is rotatably connected to the fixed shell. The rotating shell is configured to be connected to the winding wheel and rotate around a rotation axis with the winding wheel. One of the fixed shell and the rotating shell is provided with a signal transmitter. The other one of the fixed shell and the rotating shell is connected to the control panel. The control panel is provided with a signal receiver. When the signal transmitter passes through the signal receiver, the signal receiver generates a counting signal, and the control panel receives the counting signal to calculate the extension or retraction length of the cable on the winding wheel.

Systems and methods are provided for monitoring properties of a web during a roll-to-roll manufacturing process. The methods may include moving the web past a first roller such that the web contacts the first roller, wherein the first roller includes a first contact strip formed of an electrically conductive material and extends circumferentially about the first roller, applying a voltage to the first contact strip while moving the web past the first roller, such that the voltage conducts through the web to a second contact strip, measuring the voltage received by the second contact strip, determining local resistance values relative to positions of the web based on the difference in the voltage applied to the first contact strip and the voltage received by the second contact strip, and determining at least one property of the web relative to the positions of the web based on the local resistance values.