Reed Switch Unit (AT) Help


Could you explain what the (AT) unit of measure means? It is used to describe the Operating Range.

Thank You


It stands for Ampere Turns and is a measure of switch sensitivity to magnetic field, describing the field strength required to actuate the switch in terms of the product of the number of windings on a test coil (electromagnet) and the current flow through that coil.

Datasheet footnotes are often a good place to discover resources on such topics, because the numbers in a datasheet don’t mean very much at all unless the conditions of measurement are also stated. See excerpt below for example.

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Thank You for your help Rick