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An electrostatic fieldmeter, also called a static meter is a tool used in the static control industry. It is used for non-contact measurement of electrostatic charge on an object. It measures the force between the induced charges in a sensor and the charge present on the surface of an object.
When used for measuring voltage, the input impedance of the multimeter must be very high compared to the impedance of the circuit being measured; otherwise circuit operation may be affected and the reading will be inaccurate. Meters with electronic amplifiers (all digital multimeters and some analog meters) have a fixed input impedance that is ...
The charge control consists of a pressure switch built into the cell, which disconnects the charging current when the internal cell pressure rises above a certain limit; usually 200 pounds per square inch (1.4 MPa) to 300 pounds per square inch (2.1 MPa). This prevents overcharging and damage to the cell.
ESR meters fitted with protective diodes cannot be used, a battery will simply destroy the diodes and damage itself. An ESR meter known not to have diode protection will give a reading of internal resistance for a rechargeable or non-rechargeable battery of any size down to the smallest button cells which gives an indication of the state of charge.
Active balancing attempts to redistribute energy from cells at full charge to those with a lower state of charge. Energy can be bled from a cell at higher SOC by switching a reservoir capacitor in-circuit with the cell, then disconnecting the capacitor and reconnecting it to a cell with lower SOC, or through a DC-to-DC converter connected ...
In practice the conductivity cell is calibrated by using solutions of known specific resistance, ρ*, so the individual quantities l and A need not be known precisely, but only their ratio. [11] If the resistance of the calibration solution is R * , a cell-constant, defined as the ratio of l and A ( C = l ⁄ A ), is derived.
The inner electrode, which is electrically isolated from the shield, is connected to a meter to measure the charge. [1] In the field of semiconductor design, a coulombmeter consists of a meter used in combination with a metal probe tip to pinpoint locations of excess charge on, for instance a semiconductor device. This application of a ...
NiMH charge curve. To prevent cell damage, fast chargers must terminate their charge cycle before overcharging occurs. One method is to monitor the change of voltage with time. When the battery is fully charged, the voltage across its terminals drops slightly. The charger can detect this and stop charging.