Current Transformers on Energy Meters: Check Polarity, Phase Assignment and Transformation Ratio

A three-phase energy meter is connected via three external current transformers. The currents shown on...

Test Protection Relays Using Secondary Injection: Correctly Check Trip Characteristics, Time and Binary Contacts

An overcurrent protection relay is to be tested as part of commissioning or a periodic...

Store Measurement Data in an Audit-Ready Manner: Organize User Rights, Immutable Raw Data and Exports Correctly

A data logger monitors temperature, humidity, pressure or other quality-relevant measured variables over several weeks....

Bump Test Passed, Calibration Failed: Correctly Interpreting Response Time and Sensor Deviation

A portable gas detector is exposed to test gas before use. The sensor responds, the...

Determine Air Volume Flow in a Ventilation Duct from Point Measurements: Consider Measurement Grid and Flow Profile

The air volume flow in a ventilation duct is to be checked. For this purpose,...

Pressure Measurement via Microbore Hose Responds Too Slowly: Check Volume, Air Bubbles and Restriction Effects

A pressure sensor is connected to a hydraulic system via a MINIMESS® test point and...

Wireless Tank Level Monitoring: Planning Battery Life, Radio Coverage and Alarm Limits Correctly

A remote tank is equipped with a new level sensor. The measured value on site...

Mounting a Vibration Sensor: Screw, Adhesive or Magnet and Their Influence on Frequency Response

A vibration sensor is initially attached to an electric motor using a magnetic base. The...

Testing Laminar Flow and Cleanroom Airflow: Measuring Air Velocity, Grid Points and Filter Area Correctly

During the qualification of a cleanroom or laminar-flow unit, a single air velocity value is...

Cross-Sensitivities in Gas Detectors: Correctly Assessing False Alarms and Masked Gas Hazards

A portable gas detector suddenly triggers a CO alarm even though, according to the operator,...