What is a universal bridge?

Last Update Time: 2019-01-05 10:24:47

The universal bridge is an instrument made of bridge circuit balance principle, which is divided into three categories : DC bridge, AC bridge and AC / DC bridge, it can be used to measure resistance value, capacitance, inductance, quality factor, loss factor, impedance and so on, which is suitable for measuring components used in DC or low frequency range, the measuring accuracy is relatively high.

 

1.The function of the knob and switch

(1)Terminal.

It is used to connect the measured element. It is best to connect the measured element directly to the terminal. If it is not connected, the wire can be connected, the wire should be as short as possible. When necessary, the wire resistance should be removed in the measurement result. When the polar element is measured, the "1" is connected to the positive pole and "2" is connected to the negative pole.

 

(2) External socket.

When the external audio source is used, the audio signal source can be transmitted by the socket when the band switch is "outside". If the capacitance and inductance are measured with an additional DC bias, the output can be transmitted from this socket.

 

(3)Toggle switch.

The switch is placed in the "inner 1kHz" position when the oscillation signal of the 1kHz inside the bridge is used as a power supply; the switch is placed in the "outside" position when the signal power supply is lost by the external socket.

 

(4)Range selection switch.

Select the range of measurement. The indication value of each block is the maximum value of the block.

 

(5) Loss multiplier switch. It is used to extend the reading range of the loss balance. In general, when the air core inductor is measured, it is placed in the "QX1Ω" position; when the high Q inductance coil and the general small loss capacitance are measured, it is placed in the "D*0.01" position; when the core inductor and the loss of large capacitance are measured, it is placed in the "D*1" position.

 

(6) Indicating the meter.

It is used to indicate whether the bridge is balanced. When the sensitivity of the bridge is largest, the pointer of the meter is zero, indicating that the bridge is balanced.

 

(7) Bridge casing earthing end.

 

(8)bridge sensitivity adjustment knob.

The sensitivity adjustment is realized by adjusting the gain of the amplifier, and the sensitivity of the bridge is reduced when the bridge is balanced, so that the meter indication is less than the full scale, when the bridge is balanced, the sensitivity is gradually increased, and the accuracy of the bridge measurement is improved.

 

(9) Reading Disk.

The bridge is balanced by adjusting the two reading discs, and the first reading disc is a step switch, and the reading of each block is 1 / 10 of the range indication, that is, 0.1 units; the second reading disc is continuously adjusted, with a full scale of 1 / 10 of the range indication, 50 small cells, and 0.002 units per cell. 1 loss trimming knob. Adjust the loss in balance, in case of " 0 ".

 

(10)Loss balance adjustment.

The loss reading of the measured inductance and capacitance can be indicated, and the reading of the reading plate is multiplied by the indication of the loss rate switch, that is, the loss value.

 

(11)Measuring selector switch.

 The resistance measured less than 10Ω should be placed in " R10Ω"; when measuring the resistance greater than 100Ω, it should be placed in " R > 100Ω ";

When measuring the capacitance, it should be placed in " C "; the inductance should be placed in " L ";

When the meter is not in use, it should be " off ", and the internal power supply can be cut off.


This article is from Allicdata.