Off-the-Shelf (OTS) Instruments
These are instruments that you buy from a catalog and use to perform tests in the shop, lab, plant-floor, where ever that work-site might be. In some cases, where they have data ports, they can be utilized for low-level automated-testing and controlling processes when interfaced with PCs or PLC's (Programmable Logic Controllers).
Some examples include:
Coupled with the appropriate Sensor or Transducer, these basic instruments can be used to measure almost any physical property.