What is a power meter?
A force measuring device in the medical and therapeutic area is used to test muscle strength. It should be checked whether therapeutic measures are successful.
What types of power meters are there?
Mechanical power meter
To the Mechanical power meters belong to feather scales with Newton display. The disadvantage of this variant is that the extension of the spiral spring must be relatively large so that a sufficiently good resolution of the scale is achieved. A spring scale is therefore extended by about 100 mm, for example, at a measuring range of 10 N, so that a scale resolution of 0.1 n is achieved. With mechanical power meters with analog scale, the measurement path becomes considerably shorter. The compression or elongation of a spiral spring is transferred to a pointer, which increases the measuring accuracy.
Hydraulic power meter
Due to their shape, hydraulic force measuring devices are often referred to as a power jar or pressure measuring can. They are typically round and have a hollow body as well as a breakdown. As with the other force measuring devices, a metal membrane is also deformed under force. The pressure is increased proportional by the reduction in volume or the volume is displaced. Hydraulic power measuring devices of this kind can usually only measure in a stimulus and are often used for measuring very high forces.
Digital power meter
Digital power meter are usually developed on the basis of sensors with DMS (stretching strips). The minimal elastic deformation of a sensor body is transferred to a measuring grille. The line cross-section is changed by stretching or compression. The change in the cross -section causes the change in electrical resistance, which is evaluated in the measuring electronics. The nominal measurement route for digital force measuring devices is very low compared to other power meters and is between 0.1 and 0.2 mm. Another advantage is that parasitics are noticeably lower from the power impact or the location of the power meter in the room. This leads to better comparability and reproducibility of the measurement results.
What forces are measured with a force meter?
A power knife can either measure the pressure or tensile force. Normally Newton is normally considered a unit of measurement. A power knife measures the forces between two bodies and shows the measurement result analogously or digitally depending on the execution.