The bridge is generally a split-type bridge and a box-type bridge. The principle is basically the same. It is a set of circuit diagrams with a lot of resistors and meters. When the potential of two specific contacts of the line is equal, it is called Balance the bridge and use it to accurately measure the resistance. There are two types of balanced bridges and unbalanced bridges.
What is a non-balanced bridge?In practical engineering and scientific experiments, many physical quantities are continuously changed and can only be measured by unbalanced bridges. The basic principle of unbalanced bridges is to measure resistance through bridge circuits, according to the unbalanced voltage of the bridge output. Then, arithmetic processing is performed to obtain other physical quantities such as temperature, pressure, deformation, and the like which cause a change in resistance.
Bridge form of unbalanced bridge1, equal arm bridge
The four bridge arms of the bridge have the same resistance, that is, R1=R2=R3=RX0; where RX0 is the initial value of RX, and the bridge is in equilibrium, U0=0.
2, the horizontal bridge is also called the output symmetrical bridge
At this time, the bridge arm resistance of the bridge is symmetrical to the output, that is, R1 = R3, R2 = RX0, but R1 ≠R2
3, the vertical bridge is also called the power supply symmetric bridge
At this time, the bridge arm resistance is symmetrically equal from the power supply end of the bridge.
4. Proportional bridge
At this time, the bridge arm resistance has a certain proportional relationship, that is, R1=KR2, R3=KRX0 or R1=K R3, R2=K RX0, and K is a proportional coefficient. In fact this is a general form of unbalanced bridge.
Unbalanced bridge outputThe output load classification of unbalanced bridges can be divided into two types. One is that the load impedance is large relative to the bridge arm resistance, such as a digital voltmeter with a high input impedance or an operational amplifier circuit with a large input impedance; the other is a small load impedance, which is comparable to the bridge arm resistance. The latter type is also called a power bridge because the unbalanced bridge needs to output a certain amount of power.
According to the Thevenin's theorem, the bridge shown in Figure 1 can be equivalent to the two-port network shown in Figure 2(a).
When the potential of two specific contacts in the bridge is equal, that is, the bridge output of the two contacts is zero, it is called the balanced bridge.
Balanced bridge classificationThe bridge can be divided into a DC balanced bridge and an AC balanced bridge according to the excitation mode.
DC balanced bridge for DC bridge, its output voltage is:
The output voltage is:
It can be seen from the above formula: 
,
Then the output voltage must be zero, and the bridge is in equilibrium, called the balanced bridge.
Therefore, for DC balanced bridges, the equilibrium conditions are:
AC balanced bridge
For DC bridges, the output voltage is:
The output voltage is:
It can be seen from the above formula: 
, the output voltage is zero. For an AC bridge, Z is a complex number.
Then, the balance conditions of the AC bridge are:
It can be expressed as:
The relationship between the unbalanced bridge and the balanced bridge is a right and wrong relationship. A bridge that operates under unbalanced conditions is an unbalanced bridge, and a bridge that operates under balanced conditions is a balanced bridge.
Balanced bridge refers to the same midpoint voltage of the two arms, in order to test accurately and with high precision. Unbalanced bridges are relatively simple and less accurate.
Somke Machine
Fog Smoke Machine
Feature:
* DURABLE MATERIAL: It is made of top grade aluminum alloy, built-in fan for heat dissipation, stable and lightweight. Look upscale and durable for long time.
* BEAUTIFUL COLOR SHOW: It can choose single colors or color combinations. It will be great enjoyment to see the colorful light projected to the ceiling, wall and floor,etc.
* SUIT FOR VARIOUS OCCASION: Suit for various parties, birthday, dance, holiday, celebrations, Karaoke, family or friend home celebration. The laser light can be used in home, disco, living room, bar, club, or anywhere needed.
* EASY OPERATION: The light will enter sound activated mode, which makes the lights blink according to the beat of the music or sound. Adjustable motion speed.
* CREAT ATMOSPHERE EVERYWHERE: This laser light is mini size with tripod, portable and convenient for carry. You can place it everywhere.
Our company have 13 years experience of LED Display and Stage Lights , our company mainly produce Indoor Rental LED Display, Outdoor Rental LED Display, Transparent LED Display,Indoor Fixed Indoor LED Display, Outdoor Fixed LED Display, Poster LED Display , Dance LED Display ... In additional, we also produce stage lights, such as beam lights Series, moving head lights Series, LED Par Light Series and son on..
Somke Machine Series,Smoke Machine,Wedding Smoke Machine,Smoke Machine Party
Guangzhou Chengwen Photoelectric Technology co.,ltd , https://www.cwleddisplay.com