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Manganin is a trademarked name for an alloy of typically 84.2% copper, 12.1% manganese, and 3.7% nickel. It was first developed by Edward Weston in 1892, improving upon his Constantan (1887). Manganin foil and wire is used in the manufacture of resistors , particularly ammeter shunts , because of its virtually zero temperature coefficient of ...
For manganin, a common shunt material, at 80 °C thermal drift begins to occur, at 120 °C thermal drift is a significant problem where error, depending on the design of the shunt, can be several percent and at 140 °C the manganin alloy becomes permanently damaged due to annealing resulting in the resistance value drifting up or down.
Strain resistance strips are commonly used on structural pieces of steel and so on, so this manganin use should be explained more, how does it measure stress, but not strain. — Preceding unsigned comment added by 90.64.1.28 ( talk ) 18:37, 2 March 2017 (UTC) [ reply ]
Very importantly, constantan can be processed for self-temperature compensation to match a wide range of test material coefficients of thermal expansion.A-alloy is supplied in self-temperature-compensation (S-T-C) numbers 00, 03, 05, 06, 09, 13, 15, 18, 30, 40, and 50, for use on test materials with corresponding thermal expansion coefficients, expressed in parts per million by length (or μm ...
A resistance decade box or resistor substitution box is a unit containing resistors of many values, with one or more mechanical switches which allow any one of various discrete resistances offered by the box to be dialed in. Usually the resistance is accurate to high precision, ranging from laboratory/calibration grade accuracy of 20 parts per ...
To measure a low unknown resistance X, replace Y with a copper busbar that can be assumed to be of zero resistance. In practical use, when the bridge is unbalanced, the galvanometer is shunted with a low resistance to avoid burning it out. It is only used at full sensitivity when the anticipated measurement is close to the null point.
The meter comprised a moving coil meter, voltage and precision resistors, and switches and sockets to select the range. The first Avometer had a sensitivity of 60 Ω/V, three direct current ranges (12 mA, 1.2 A, and 12 A), three direct voltage ranges (12, 120, and 600 V or optionally 1,200 V), and a 10,000 Ω resistance range.
If the length of the R 1 resistance wire is AB, where A is the (-) end and B is the (+) end, and the movable wiper is at point X at a distance AX on the R 3 portion of the resistance wire when the galvanometer gives a zero reading for an unknown voltage, the distance AX is measured or read from a pre-printed scale next to the resistance wire.