What is the difference between a bridge resistance measurement and a multimeter resistance measuring resistor?
Bridge resistance measurement and multimeter resistance measuring resistance, mainly the principle is different:The electric bridge measures the resistance and produces a constant current source inside it. By collecting the voltage at both ends, the resistance is calculated, so the accuracy of measuring low resistance is very high, and the maximum can reach 0.01%.
Multimeter resistance profile, resistance test, is a constant voltage source, voltage division principle, calculate the corresponding resistance value, so the resistance is far greater than the multimeter resistance value, the measurement precision is high, the accuracy of normal around a few percent (ps: now some of the imported desktop multimeter is precision very high, but not this principle).
Measure resistance bridge, through the galvanometer to judge the bridge of "balance" has nothing to do with the power supply voltage, the measurement precision is high.Multimeter resistance profile measuring resistance, is based on the principle of closed circuit Ohm law to work, because of uneven resistance scale, the measurement precision is low. Especially the battery after long use, the electromotive force and internal resistance will have obvious changes, directly affect the accuracy of measurement.It can be said that one is the sky, the other is the earth, and their measuring accuracy is no better than that of the earth
