Dedicated 35kV Surge Generator XHHV535-4T with 2450J Discharge and Three Operating Modes for Cable Fault Pinpointing

Multi-voltage surge generators compromise at each voltage step — capacitor values, discharge timing, and energy distribution are averaged across ranges. The XHHV535-4T eliminates this compromise by dedicating its entire power stage and 4μF capacitor to the 35kV class. The result: 2450 joules of clean, controlled discharge energy optimized for medium-voltage cable networks from 33kV to 35kV.

For utilities and contractors whose fleet operates primarily on 35kV distribution and sub-transmission cables, a dedicated unit means no voltage selector errors, no accidental energization at the wrong range, and consistent surge characteristics across every fault location event.

The XHHV535-4T's control layout follows a logical left-to-right operating sequence, minimizing training time and reducing operator error in field conditions:

• DC High-Voltage Source: Built-in step-up transformer and rectifier, producing clean DC output from 0 to 35kV without external HV power supply
• Energy Storage Capacitor: 4μF dedicated capacitor, matched to the 35kV output stage for optimal energy density and discharge timing
• Discharge Sphere Assembly: Precision-machined discharge gap within shielded enclosure, producing controlled, repeatable surge characteristics for each discharge cycle
• Automatic Discharge Circuit: On Stop command or power loss, the internal capacitor is automatically discharged through a safety bleed resistor — voltmeter drops to zero, confirming safe state before cable disconnection

1. Pre-Locate: Connect a TDR cable fault locator (XZH TEST 502 series) to identify the approximate fault distance. The 4T's internal waveform sampling module provides a clean Q9 trigger signal for synchronized TDR acquisition
2. Set Mode: Select Auto Cycle mode for acoustic-magnetic pinpointing, or DC Withstand for pre-repair insulation verification
3. Zero-Check and Start: Confirm yellow zero indicator is lit, press Start, then increase voltage to the target surge level via the voltage control knob
4. Pinpoint: In Auto Cycle mode, the 4T delivers 2450J discharges every ~5 seconds. Deploy an acoustic-magnetic pinpointer (XHDD503) along the pre-located cable section to capture discharge sound and electromagnetic signals, narrowing the search to the exact fault position
5. Stop and Discharge: Press Stop — the 4T automatically cuts HV output and discharges the internal capacitor. Verify voltmeter reads zero before disconnecting output cables