Ammeter to be measured with both polarities, common in scientific and industrial equipment. Zero-center ammeters are also commonly placed in series with a battery. In this application, the charging of the battery deflects the needle to one side of the scale (commonly, the right side) and the discharging of the battery deflects the needle to the other side. A special type of zero-center ammeter for testing high currents in cars and trucks has a pivoted bar magnet that moves the pointer, and a fixed bar magnet to keep the pointer centered with no current. The magnetic field around the wire carrying
Electrical cardiometry Electrical cardiometry Electrical cardiometry is a method based on the model of "Electrical Velocimetry", and non-invasively measures stroke volume (SV), cardiac output (CO), and other hemodynamic parameters through the use of 4 surface ECG electrodes. Electrical cardiometry is a method trademarked by Cardiotronic, Inc., and is U.S. FDA approved for use on adults, children, and neonates. The measured bioimpedance over time can be expressed as the superposition of three components: where Z is the quasi-static portion of the electrical impedance (base impedance), ΔZ are the changes of impedance due to the respiratory cycle, and ΔZ are the changes of impedance