SF₆ Leak Detector Shows Fluctuating Values: Correctly Checking Background Concentration and Sensitivity
During SF₆ leak detection, the cause initially seems obvious: The probe is held near a...
Finding Insulation Faults in PV Strings: Systematically Identifying Polarity, Ground Faults and Moisture
The inverter reports an excessively low insulation resistance, fails to start or repeatedly shuts down...
Flow Switch Operates Unreliably: Checking Installation Position, Minimum Flow and Hysteresis
A flow switch should reliably detect whether a sufficient quantity of medium is flowing in...
Automatic Pressure Controller Does Not Reach the Setpoint: Checking Volume, Leakage and Control Parameters
An automatic pressure controller should approach specified pressure points quickly, stably and reproducibly. In practice,...
Speed Sensor Loses Pulses: Correctly Checking the Air Gap, Target Wheel and Switching Frequency
A fluctuating speed indication, sporadically missing pulses or brief overspeed alarms are often attributed prematurely...
Catalytic Gas Sensor Poisoning: Detecting Silicone, Sulphur and Loss of Sensitivity
A catalytic gas sensor may appear to be in perfect condition, indicate a stable zero...
Event-Triggered Recording of Pressure Spikes: Correctly Configuring Trigger, Pre-Trigger and Sampling Rate
Rare pressure spikes are among the most difficult faults to diagnose in hydraulic systems, test...
Correctly Measuring Milliohms and Microohms: Four-Wire Kelvin Measurement and Avoiding Contact Errors
For busbars, circuit breakers, welded connections or high-current cables, just a few microohms can make...
Residual-Current Relay Trips with Frequency Converters: Correctly Assessing Leakage Currents and Frequency Components
During normal operation, frequency converters generate leakage currents that flow back to the power supply...
Evacuating SF₆ Filling Hoses Before Filling: Reliably Preventing Air and Moisture Ingress
When topping up an SF₆ gas-insulated switchgear system, attention is often focused primarily on achieving...