Lightning Protection Component Tester: MOV Leakage Current and GDT Breakdown Voltage Testing

Why Testing Lightning Protection Components Is Essential

Surge protection devices (SPDs) are critical components in lightning protection and power quality systems, but their protective capability degrades over time with each surge event they absorb. Metal oxide varistors (MOVs) gradually lose their clamping ability as repeated surges degrade the zinc oxide material, while gas discharge tubes (GDTs) can develop delayed firing or increased breakdown voltage after exposure to high energy surges.

Regular testing of these components ensures that the surge protection system remains effective. Degraded components that are not identified and replaced leave connected equipment vulnerable to damage from lightning-induced surges and switching transients. EK Instruments provides specialized testers for each type of surge protection component.

MOV and GDT Tester: EK-C380A

The EK-C380A tests the two most common types of surge protection components: metal oxide varistors and gas discharge tubes. For MOV testing, it measures leakage current from 0 to 1000 microamperes, which is the primary indicator of MOV health. As an MOV degrades, its leakage current at the rated voltage increases. When leakage current exceeds the manufacturer-specified limit, the MOV must be replaced.

For GDT testing, the EK-C380A measures DC breakdown voltage from 50V to 3000V. The breakdown voltage is the voltage at which the gas discharge tube fires and begins conducting. GDTs that fire at significantly higher or lower voltages than their rated value are no longer providing proper protection and require replacement.

The touchscreen color display provides clear test results, lithium battery power ensures field portability, and USB interface supports data documentation and reporting.

Multi-Function Model with Insulation Testing: EK-C380B

The EK-C380B adds insulation resistance measurement (500V and 2500V test voltage, up to 10 gigohm) to the MOV and GDT testing functions. This combination is particularly valuable for lightning protection system inspectors who need to test both surge protection components and the insulation integrity of the overall lightning protection installation during a single site visit.

The insulation resistance function can verify the isolation of lightning protection conductors from building electrical systems, test the insulation of surge protection device housings, and assess the condition of cable insulation in lightning protection circuits.

TVS Diode Tester: EK-C385

The EK-C385 is specifically designed for testing transient voltage suppressor (TVS) diodes, which are increasingly used in electronic equipment protection and signal line surge protection. It measures the reverse breakdown voltage of TVS devices across a range of 0 to 400V.

TVS diodes are used to protect sensitive electronic circuits from voltage transients on data lines, communication circuits, and low-voltage power supplies. Testing verifies that the TVS breakdown voltage matches the device specification, ensuring that connected circuits receive proper protection without false triggering during normal operation.

Calibration Standard: EK-C390

The EK-C390 is a multi-decade standard resistor designed for calibration verification of ground resistance testers, equipotential bonding testers, and other resistance measurement instruments. It provides eight standard resistance values: 1 milliohm, 10 milliohm, 100 milliohm, 1 ohm, 10 ohm, 100 ohm, 1 kilohm, and 100 kilohm.

Having a reliable calibration standard on hand enables field verification of instrument accuracy before critical testing sessions, ensuring that measurement results are trustworthy and compliant with testing standards. The EK-C390 is an essential accessory for any professional electrical testing program that requires documented measurement accuracy.