Voltage spikes are sudden, sharp, large rises in circuit voltage.

Spikes can be caused by a number of different factors, but you should remember that voltage spikes can do serious, permanent damage to electronic components.

Caution: Voltage Spiking Produced by Relays and Solenoids

It should be noted that, when we de-energise a relay or solenoid by switching off the supply to the switching coil, the associated magnetic field around that coil will suddenly collapse.

We know that a magnetic field moving across a conductor will produce electricity. In a relay or solenoid, the magnetic field is quite strong (strong enough to close the contacts or solenoid), and there are a lot of turns of wire in the switching coil.

This means that, when we suddenly switch off a relay or solenoid, the magnetic field moving rapidly across the large number of turns in the switching coil, will produce a significant voltage spike that can harm any electronic devices that may be in the circuit.

You can read more about relays and solenoids here on CP Fitters

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