What Is a Microprocessor Controlled Test System?

A microprocessor controlled test system is a test machine whose sequence, safety interlocks and measurements are managed by a microprocessor-based controller, most often a programmable logic controller (PLC) or an industrial computer with data acquisition. It replaces manual valve handling and hard-wired relay logic with software, which makes tests faster, safer and more repeatable.

How a microprocessor controlled test system works

The controller reads inputs from sensors such as pressure transducers, flow meters, temperature sensors and position sensors. It runs a programmed test sequence, and sends outputs to pumps, valves and motors to ramp, hold and release pressure. It compares measured values with limits, decides pass or fail, and stores the results. An operator normally works through a touchscreen human-machine interface (HMI), while a supervisory system (SCADA) or a PC-based data acquisition system provides trends, alarms and reports.

Benefits of microprocessor control in testing

Repeatability: every article gets the same ramp rate, hold time and acceptance criteria, independent of the operator.
Safety: interlocks stop a test if a guard is open or a limit is exceeded, and pressure is only applied when conditions are correct.
Speed and accuracy: the controller reacts to pressure and flow changes faster than a person can.
Recipes: stored test programs for different parts can be selected rather than set up by hand.
Traceability: results, curves and reports are stored for quality records and can usually be exported, for instance as files, for analysis.

Examples on Neometrix test systems

The computerized microprocessor controlled DV test bench page describes an automated, microprocessor-controlled system for railway distributor valves, with data acquisition and reporting. The universal hydraulic test rig page describes a PLC-controlled rig with an HMI and pre-loaded test recipes. The hydraulic proof pressure test rig page describes a PLC-controlled proof pressure rig and the hydraulic pressure test bench page a SCADA-integrated hydrostatic and burst test system. On the control valve test rig page, a National Instruments data acquisition platform with a touchscreen provides live charts and automated pass or fail logic. These are different controller types, so the exact architecture depends on the test system.

PLC, industrial PC or DAQ: which controller?

A PLC is robust and well suited to sequencing, interlocks and closing pressure loops in a factory environment. An industrial computer with data acquisition hardware is stronger for high-rate measurement, graphing and flexible reporting. Many test systems combine the two: a PLC handles control and safety while a PC records data and generates reports. The choice depends on measurement rate, safety requirements and how the results will be used, for example to verify a valve's hysteresis or relief valve settings.

Frequently asked questions

What is microprocessor control in a test system?

It is the use of a microprocessor-based controller, such as a PLC, to run the test sequence, monitor sensors, enforce safety limits and record the results automatically.

What is the difference between a PLC and a microprocessor?

A microprocessor is the processing chip; a PLC is an industrial controller built around one, with rugged inputs and outputs and programming suited to machine control.

Why use automation instead of manual testing?

Automation applies the same test parameters every time, reacts faster than an operator, applies safety interlocks and stores results for traceability.

What is SCADA in testing?

SCADA (supervisory control and data acquisition) is software that displays, trends and records data from the controller and can raise alarms and generate reports.

Can test results be exported from a controlled test bench?

Usually yes. Controlled test systems store results and can normally export them to files for quality records, though the formats depend on the specific system.

To specify automation for your test bench, contact the Neometrix team.