Hello, friends, I hope you all are doing great. In today’s tutorial, we will discuss the Difference Between AC & DC Bridge. The main difference between AC and DC bridge circuits is that the AC bridge used to find the value of the unknown impedance of circuitry and DC bridge circuit is used to find the value of th unknown resistance of a circuit.
In today’s post, we will have a detailed look at both ac and dc bridges with the details and compare them to find their differences. So let’s get started with Difference Between AC & DC Bridge.
Difference Between AC & DC Bridge
AC Bridge
- The circuitry that is used to find the value of the unknown impedance of any circuitry is called an AC bridge.
- It is given that AC supply as input.
- It is alternating the current detecting circuit.
- It is the analog circuit of the Whetstone Bridge.
- It has 4 limbs with a balanced detector and power supply configuration.
- It is used to solve different problems in communication systems and complicated circuits can be solved through this.
- It is used for shifting phase circuits and measuring the value of frequency.
- The components of this circuitry are resistive and reactive.
- It uses Wagner’s Earthing device.
- There are 2 types of ac bridge circuits.
- The balancing time required for this circuitry is less.
- The value of inductance capacitance can be found through this circuitry.
- In case of calculation of less value frequency, the supply line is the source of the bridge.
DC Bridge
- The DC bridge is used to find the value of unknown resistance.
- It used a dc power supply as input.
- It consists of four limbs with a power source and galvanometer.
- The value of the current relies on the potential of the meter.
- It has a balanced structure when no current about the meter
- It is DC detector module.
- Kelvin bridge is an example of dc bridge
- It used resistance in the circuitry.
- It does not use Wagner’s Earthing device.
- There are 7 types of dc bridge circuits.
- Its balancing time is high.
AC Beidge Vs DC Bridge
- The bridge circuit that is used to measure the unknown impedance of any circuit is called the Wheatstone bridge. So this DC bridge that used to measure the unknown component resistance in the circuit
- AC supply is used for the AC bridge and the DC bridge uses dc supply to measure the resistance
- For the current detector, ac detector is used in ac bridge and dc detector is used in the dc bridge
- The resistive and reactive elements are used in ac bridge and for the dc bridge only resistive components used
- There is a Wagner earth used for the elimination of earth capacitance in the circuit which also reduces the harmonics and faults existing due to the magnetic field. While for DC bridge Wagner earthing is not used
- AC bridge needs less time and dc bridge needs more time for balancing.
- Common types of AC bridges are that are
- Hay’s Bridge,
- Anderson Bridge,
- Schering bridge,
- Wein bridge.
- capacitance comparison bridge
- inductance comparison bridge
- Maxwell’s Bridge,
Types of AC Bridges
There are different types of AC bridges and each perform different operations. There are many types of AC bridges based on applications.Some types are listed here
Maxwell’s Bridge
- Maxwell bridge is used for measuring the inductance of inductors by balancing bridges with known resistors and capacitors. This bridge type is accurate and used for laboratory settings. The working featues of Maxwell’s Bridge is given by:
LR1=R2R3𝐿𝑅1=𝑅2𝑅3
- Here L is inductance, 𝑅1, R2, and 𝑅3 are known resistors.
Hay’s Bridge
- This bridge is like the Maxwell bridge and is used for measuring inductance but used for high-quality inductors having low resistance. it provdies easier configuration than the Maxwell bridge. Hay bridge is a technique for measuring inductance, best used for inductors that have less resistance value. The balance equation is like Maxwell’s Bridge but needs more resistors for good accuracy.
Schering Bridge
- Schering Bridge is made for measuring capacitor capacitance, in a power system. it is used for testing insulation and dielectric features of electrical devices. It uses known resistor values and capacitors for balancing the bridge and measures unknown capacitance.
The balance equation for the Schering Bridge is:
Cx=C2⋅R3R4𝐶𝑥=𝐶2⋅𝑅3𝑅4
Here
- 𝐶𝑥 is the unknown capacitance,
- 𝐶2 is a known capacitor,
- 𝑅3 and 𝑅4 are known resistors.
Wien’s Bridge
- This type of bridge is used for measuring frequency and is known for its easy-to-use features. it is best to use for audio and radio frequency measuring applications. This bridge type measures frequency by balancing the bridge with known resistors and capacitors. It is highly accurate for audio and frequency uses.
equation for Wien’s Bridge is:
f=12πRC𝑓=12𝜋𝑅𝐶
- 𝑓 is the frequency,
- 𝑅 and 𝐶 are known resistor and capacitor values.
Read also:
- Difference Between Alternating Current (AC) and Direct Current (DC)
- Introduction to MB10S Bridge Rectifier
- Internal Generated Voltage and Torque Equation of DC Machines
Faqs
What is the purpose of the AC bridge?
- A bridge offers security since it separates different parts of the circuit from each other. Bridges offer network redundancy through connecting two or more paths between different parts of circuits. Bridges are used for forwarding frames without varying sources and located points
What is the function of the DC bridge?
- Mostly DC bridges are used for measuring resistance, and a bridge powered with AC can be used for measuring different electrical parameters such as inductance, capacitance, and frequency.
What are three main differences between AC and DC?
- The power factor of AC is zero to one and dc is constant zero. The AC is generated through alternator and photovoltaic cells, generators and batteries produce DC. The AC load can be capacitive inductive, or resistive and DC is resistive.
What is the basic principle of AC bridge?
- The AC bridge circuit works with the same principle as DC bridge circuits, that a balanced ratio of impedances and causes balanced condtion as shown with a null-detector device.
What are the advantages of DC bridge?
- The DC bridge measures the unknown resistance of the circuit. The digital voltmeter measures voltage through an analog-to-digital converter and digital display. it provides advantages then analog voltmeters such a high accuracy from picovolts to megavolts. Common applications are electrical equipment monitoring
What are examples of DC bridges?
- main examples are Wheatstone Bridge and Kelvin bridge. The Wheatstone bridge is used for balancing circuit configuration with two parallel resistance branches for correct measure of unknown resistance.
What is the balance condition for DC bridge?
- DC bridge circuit is used for measuring the resistance of the circuit, a balanced condition in a dc bridge circuit is obtained when multiple of two opposite resistances are equal.
That is a detailed post about the difference between AC Bridge and DC Bridge. If you have any queries ask in the comments. Thanks for reading. Have a good day.
