Voltage measurer with wide measuring range

Abstract

A voltage measuring device with a wide measurement range, its first stepping plate is composed of 21×100Ω measuring plate and auxiliary plate I’ and I” without resistance, and the second stepping plate is composed of 9×90Ω The ring resistance and two 10Ω resistor nets constitute the measuring panel, and the 10×5Ω resistor forms the auxiliary panel, and the third panel is a double-sliding line panel, and the two measuring panels are connected with the measuring sliding wires with wires, and the voltage is not switched by a switch. The measuring device has no variation and thermoelectric potential influence during the DC voltage measurement, and the replacement disks of the first and second stepping disks are omitted. This voltage measuring device has four types: ×10, ×1, ×0.1, ×0.01 The maximum measurement voltage is 2.31V, and the high and low resolution is 0.1μV.

Description

technical field [0001] The invention relates to an instrument for measuring DC voltage. Background technique [0002] At present, for the potentiometer with three measuring discs, in the connection between the three measuring discs, the intermediate disc is generally switched by a switch, which will cause a change in contact resistance and limit the resolution. In order to overcome this problem, large brushes are generally used to increase the contact area, and silver-copper composite materials are used; Patent No. ZL200520101772.0 discloses a new method for solving the deterioration of switch contact resistance by a potentiometer with three measuring discs. The first and second stepping discs are composed of a measuring disc, a substituting disc and an auxiliary disc. The resistance values ​​on the measuring disc and the substituting disc are the same. Every time a resistance is added to the measuring disc, the substituting disc will reduce the same resistance. , since the...

AI Technical Summary

Problems solved by technology

After the two measuring discs are connected, they are connected with the sliding wire disc between the two measuring terminals, so that the brushes on the switch of the stepping disc are excluded from the measuring circuit, and there is no switching between the resistances on the three measuring discs, and There will be no deterioration; since the first and second stepping discs have replacement discs, the number of layers of the first and second stepping discs welded with resistance is increased, thereby increasing the volume of the instrument and making the switch and the instrument structure becomes complex

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