Basic Considerations In Choosing An EFT Generator

Each model and make of EFT generator in the market is slightly different, but most will have a similar set of steps and operating protocols. EFT stands for electrical fast transient and it is testing required to obtain the CE mark to be able to sell into the European Economic Area or EEA.

A transient is a burst of energy, typically always a very short burst, that is a direct result in the change of state in an electrical component. This change in state can be a result of something internal within the device or component, or it can be caused by something outside of the part or component.

One of the most common causes of EFT internally is when motors, switches and relays are powered down, producing bursts of EFT across the system. They can also be caused by spikes in the mains power or sparking that can occur on a system when a cord is plugged in or an electronic device is turned off. Even something as significant as turning off and on a breaker can produce transients.

The Use of the Generator

The EFT generator is designed to produce a specific test voltage waveform for a specific type of transient. This could include changing of the loads on a system, often by replicating the action of these pulses into the AC power supply lines to the device.

However, different applications may also include the generation of transients from grounds or from signal and control lines; it will all depend on the specific standards and requirements for the component and part.

Ideally, through the use of the generator, the device or component will be tested and found immune to transients based on the standard being used. Devices can be tested to more than one standard as some types of components can be used across multiple industries.


The selection of an EFT generator will depend on the specific testing requirements. This can also reflect if the testing equipment has to be a standalone tester or used with a multi-functional type of testing system.

Additionally, the burst voltage will be considered as well as the spike frequency. Consider also the need for a single phase coupler or a three-phase coupler based on specific testing requirements. Some systems come complete with a touch screen for easy operation, which can make using the generator very easy within only a few minutes of use.