What is MOV component?
A Metal Oxide Varistor (MOV) is a protection component used in power supply circuits that is powered directly from AC mains. It is used to protect the circuit from high voltage spikes by varying its resistance.
How do I test a MOV with a multimeter?
Turn the multimeter on and set its function knob to read resistance. Touch the meter probe tips to the MOV’s leads and measure its resistance. If it has a resistance much under 100 ohms, it has blown. Desolder and remove the remaining lead and remove the MOV from the equipment.
What is the purpose of a MOV?
This type is commonly known as the metal-oxide varistor (MOV). Varistors are used as control or compensation elements in circuits either to provide optimal operating conditions or to protect against excessive transient voltages.
Where does MOV go in circuit?
The MOV is placed between the power supply mains and the circuit to be protected from the high voltage spikes is shown below. The resistance of the MOV is changed automatically based on the Voltage applied to the circuit.
What is the use of MOV?
What is clamping voltage of MOV?
Clamping voltage: It is the voltage at which the MOV starts to conduct and dissipate the surge current. Surge Current: It is the maximum peak current that can be given to the device without causing any device damage; it is mostly expressed in ‘current for a given time’.
What is a MOV surge protector?
A Metal Oxide Varistor (MOV) is a voltage dependent resistor. In other words, it’s an electrical component whose resistance varies with voltage. They are used to protect vulnerable circuit components from short surges of electrical energy.
What is the full form of electronic components MOV?
Metal-Oxide Varistor (MOV) is a common type of varistor. This contains a ceramic mass of zinc oxide grains sandwiched between two metal plates.
What happens when MOV fails?
A. When subjected to stresses above its ratings, an MOV can fail as a short circuit. If applied conditions significantly exceed the energy rating of the device, and current is not limited, the MOV may be completely destroyed. For this reason, the use of current-limiting fuses is suggested.
What happens when a MOV is detected in a circuit?
But, every time a spike is detected the MOV disconnects the circuit momentarily by shorting itself and damaging itself with high current each time. So if you find a MOV damaged in any power circuit it is possibly because the circuit went through many voltage spikes.
What causes the performance of a MOV to change?
Another main reason that affects the performance of a MOV is the energy rating. When there is an increase in the energy rating, there will be an exponential change in the life of the varistor. Thus, there will be a change in the transient pulses that the device can manage. This increases the clamping voltage when each transient breaks down.
How does a metal oxide varistor ( MOV ) work?
What is a MOV (Metal Oxide Varistor)? MOV is simply a variable resistor, but unlike potentiometers, MOVs can change its resistance based on the applied voltage. If the voltage across it increases the resistance decreases and vice versa.
What kind of applications can MOV be used for?
Applications of MOV The MOVs can be used for protecting various types of equipment from different types of faults. They can be used for single-phase line to line protection and single-phase line to line & line to ground protection in AC/DC electrical circuits.