Bridge Rectifier Failure Symptoms | Factors Leading to Bridge Rectifier Breakdown

A bridge rectifier is an electrical component that transforms AC into DC in electronic circuits. However, when it cannot convert AC into DC anymore, it is considered failing. A bridge rectifier failure may show different symptoms while failing. 

In this article, we will discuss some of the symptoms of bridge rectifier failure.

What are the Symptoms of Bridge Rectifier Failure?

A common component such as a bridge rectifier can exhibit several symptoms when failing. Here are some commonly exhibited symptoms:

Absence of Output Voltage and Overheating: 

One of the most prominent signs of bridge rectifier failure is the absence of output voltage or a significant drop in the output voltage. Due to increased resistance or short circuits within the component, it also becomes hot to the touch.

Burning Smell:

Overheating can lead to a burning or acrid smell coming from the rectifier. This odor can be an early warning sign of a problem.

Excessive Ripple Voltage: 

A failing rectifier cannot smooth out the AC waveform to produce relatively stable DC output. It might introduce excessive ripple voltage that might cause instability in the signal.

Voltage Fluctuations: 

The output voltage may fluctuate, which can disrupt the operation of devices connected to the power supply. A failing bridge rectifier may produce audible noise, such as buzzing or humming sounds.

Visual Damage:

The rectifier shows visible signs of damage such as burn marks, discoloration, or cracked components. 

Blown Fuses: 

If the bridge rectifier develops a short circuit, it can cause fuses to blow in the power supply circuit.

Increased Heat in Surrounding Components:

When a bridge rectifier fails, it can affect other components in the power supply circuit. Increased heat in nearby components or areas of the circuit board can be an indication.

Voltage Spikes or Surges: 

A failing bridge rectifier may introduce voltage spikes or surges into the output, which can potentially damage connected devices.

Frequently Asked Questions and Answers (FAQ)

What is the Main Cause of Bridge Rectifier Failure?

Generally, the main cause of bridge rectifier failure is short-circuit and bad insulation. If the heat sink is not large enough, the overload impulse current is too large. Therefore, the heat cannot be emitted. 

How do I Know if My Rectifier Diode is bad?

A diode is reverse-biased when the positive test lead is on the cathode and the negative test lead is on the anode. The reverse-biased resistance of a good diode displays OL on a multimeter. The diode is bad if readings are the same in both directions.

Can a Rectifier be Replaced?

You can either replace the entire rectifier regardless of the integrity of the core components or upgrade the controls and functionality at the time of part obsolescence. The rectifier can also be refurbished by cleaning and reassembling every square inch of the power supply.

Conclusion

Although a bridge rectifier failure can be caused by a variety of circumstances, it is best to turn off the power and physically check the component if you suspect one. If the problems persist, it is advisable to visit a competent expert or replace the rectifier as needed.