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What is an Ignitron?

Jean Marie Asta
Jean Marie Asta

An ignitron is a device that is a type of controlled rectifier used to convert an alternating current, or AC, to a direct current, or DC. These devices are often used in the industrial and utility industries for electrical purposes. While there are other ways to convert an alternating current to a direct current, the ignitron is a preferred method. This is because it is durable and resistant to the damage that can be caused by electrical problems like back-voltage or overcurrents.

A steel container is the basis for the ignitron. This container is typically fairly large and it will contain mercury at the bottom to act as a cathode. The device also includes an igniter, which is a small electrode that must touch the pool of mercury in the container. Applying an external voltage source to the igniter will start the device, creating a conducting arc in the ignitron tube. The arc will last until the outside voltage power source has lost too much power or has been removed.

Man with a drill
Man with a drill

Due to the mercury that is used in an ignitron device, it must be properly set up. Mercury needs to be still, so the device’s container and tube must be vertically aligned with no lean. Otherwise, the mercury can be moved and the igniter may not touch the cathode. This will fail to create a conducting arc in the device, and thus it will render it useless. For maximum results, the ignitron should always be upright and in a stable, secure location.

Ignitrons have been used in many different applications in various industries. One of their more popular uses was in the welding industry, as they were used to control the currents flowing through electric welding machines. These machines were used in the locomotive industry as well, for both electric motors and transformers. Ignitrons were used to help power the lines used for trains or trolleys to get to and from their designated locations. They also used to be used in aluminum smelting factories; however, most ignitrons in this field have been replaced with newer technology.

While some industries use newer equipment for their current conversion needs, many industries still use the ignitron device. This is because ignitrons have been redesigned over the years to make them more effective. They can be used inside vacuum tanks now, and they also can be customized to include pulsed power applications, which can help this conversion device operate more efficiently.

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