VOLTCRAFT ET-400 Insulation Tester 250 V, 500 V, 1000 V, 2500 V up to 2.5 TΩ (VC-17072210)

Measure insulation resistance up to an extraordinary 2.5 TΩ with test voltages of 250 V, 500 V, 1000 V, and 2500 V. The VOLTCRAFT ET-400 delivers laboratory-grade accuracy in a rugged handheld design, making it the definitive tool for diagnosing cable integrity, motor windings, and electrical installations.

Overview

The ET-400 is a professional insulation tester engineered for demanding preventive maintenance and troubleshooting. It covers a full spectrum of electrical measurements: insulation resistance, AC/DC voltage, low resistance, capacitance, and frequency. With CAT IV 600 V and CAT III 1000 V safety ratings, it is safe for use on utility connections and industrial distribution systems. The large backlit LCD ensures readability in dark or confined spaces, while the auto-discharge function safely dissipates residual voltage after each test.

What stands out

• Wide insulation resistance range from 0.01 MΩ to 2.5 TΩ across four test voltages.
• Integrated PI (Polarization Index) and DAR (Dielectric Absorption Ratio) diagnostics for assessing insulation quality over time.
• Data logging for up to 9999 measurements with USB and Bluetooth connectivity for easy reporting.
• Dual power options: 8 AA batteries or AC adapter for continuous bench operation.
• Built-in timer for automated test sequences and consistent results.

Technical details

• Test voltages: 250 V, 500 V, 1000 V, 2500 V
• Insulation resistance range: 0.01 MΩ to 2.5 TΩ
• DC voltage: 0.1 V to 1000 V; AC voltage: 0.1 V to 750 V
• Resistance: 0.01 Ω to 20 kΩ; Capacitance: 0.01 nF to 25 µF; Frequency: 0.01 Hz to 1 kHz
• Short-circuit current: < 1.8 mA
• Safety: CAT IV 600 V, CAT III 1000 V
• Display: Backlit LCD
• Data logging: 9999 memory locations
• Connectivity: USB, Bluetooth
• Power: 8x AA batteries or AC adapter
• Operating temperature: 0 to 40 °C
• Auto-discharge function: Yes

Our verdict

The ET-400 is a top-tier insulation tester that combines extreme measurement range, advanced diagnostics, and robust safety. It is an excellent investment for electricians and maintenance professionals who demand precision and reliability.