A measuring instrument that lacks electronic logging or digital transmission capabilities for data collection is defined as a manually read caliper. These devices, typically constructed from stainless steel or other durable materials, feature a sliding jaw that allows users to accurately measure internal dimensions, external dimensions, depth, and step distances. Readings are obtained by visually interpreting the position of the sliding jaw against a graduated scale, often a vernier scale, providing precise measurements down to a fraction of a millimeter or inch. For example, determining the outer diameter of a pipe using this type of caliper involves placing the pipe between the jaws and directly reading the measurement from the scale.
The absence of electronic components in these calipers provides certain advantages. Their simplicity of design contributes to enhanced reliability and resistance to environmental factors such as moisture, dust, and electromagnetic interference. Furthermore, these instruments are generally more cost-effective than their digitally equipped counterparts. Historically, these calipers represent a fundamental tool in manufacturing, engineering, and quality control, offering a readily available and independent method for dimensional verification. Their continued usage reflects their enduring practicality and accuracy in situations where immediate, on-site measurements are required without the need for digital data management.
