Monitoring
Capacitance & Tan Delta Tester
Integrated HV Diagnostics | Variable Frequency Testing | Oil & Solid Insulation Analysis
All-in-One Insulation Assessment
This advanced tester combines capacitance (Cx) and dielectric loss (tan δ) measurement in a single integrated platform, featuring built-in HV generation, SF6 reference capacitor, and frequency conversion for precise insulation diagnostics per IEC 60250.
Core System Components
| Component | Function | Technical Advantage |
|---|---|---|
| Variable Frequency Power | 30–300Hz adjustable output | Eliminates interference from grid harmonics |
| Boosting Transformer | Generates 10kV AC (max) | Direct testing without external HV source |
| SF6 Standard Capacitor | NIST-traceable reference (100pF ±0.05%) | Ensures ±0.1% tan δ accuracy |
| Test Bridge | Automated Schering bridge circuit | Measures Cx and tan δ simultaneously |
| Inverter HV Source | Clean sine wave (<0.5% THD) | Prevents measurement distortion |
Key Specifications
| Parameter | Specification |
|---|---|
| Capacitance Range | 1 pF – 1 μF |
| Tan δ Resolution | 0.0001 |
| Test Voltage | 0.5–10 kV AC |
| Frequency Range | 30 Hz – 300 Hz (1 Hz steps) |
| Accuracy | ±(0.5% Cx + 0.5 pF), ±(1% tan δ + 0.0001) |
| Temperature Control | Optional: -20°C to +100°C (oil tests) |
| Safety Compliance | IEC 61010-1 CAT IV 10kV |
Testing Capabilities
1. Solid Insulation Diagnostics
Transformers/Bushings: Detects moisture ingress & insulation aging
Cables/GIS: Identifies voids & delamination
Surge Arresters: Measures ZnO degradation
2. Insulating Oil Analysis (with Accessories)
| Accessory | Function | Standard |
|---|---|---|
| Insulation Cup | Precision oil test cell | IEC 60247 |
| Peltier Heater | Temperature stabilization (±0.5°C) | ASTM D924 |
| Agitation System | Eliminates bubbles during testing | ISO 3013 |
Workflow: Automated Testing
Connection
Connect test object to HV/LV terminals
Frequency Optimization
Auto-selects 40/50/60Hz or sweeps for resonance avoidance
Measurement
Applies voltage → computes Cx/tan δ in <15 seconds
Diagnostics
Flags deviations from IEEE 286 thresholds
Reporting
Prints IEC 60505-compliant pass/fail certificates
Critical Applications
| Equipment | Test Voltage | Acceptance Threshold | Fault Detected |
|---|---|---|---|
| Transformer Bushings | 10 kV | tan δ ≤ 0.005 @ 20°C | Moisture ingress >15 ppm |
| HV Cables | 2–5 kV | ΔCx ≤ 1% (Y-Y) | Shield deterioration |
| Generator Stators | 6–10 kV | tan δ ≤ 0.02 @ 130°C | Thermal aging of epoxy mica |
| Insulating Oil | 1 kV | tan δ ≤ 0.001 @ 90°C | Oxidation byproducts |
Competitive Advantages
| Conventional Testers | This Solution |
|---|---|
| Separate HV source required | All-in-one design (no external gear) |
| Fixed 50/60Hz testing | Variable frequency for noise immunity |
| Manual bridge balancing | Auto-calibration in 3 seconds |
| No oil testing capability | Integrated oil analysis with add-ons |
Related PRODUCTS
-
LQ610 DC HV Generator | 120kV Arrester & Cable Tester | GB 11032-89 Compliant
-
LQ609 (Capacitance & Tan Delta Tester)
-
LQ608 Digital Partial Discharge Tester
-
LQ607 (Standard Voltage Divider AC/DC High Voltage Series)
-
LQ605 DC Resistance Tester
-
LQ606 (Repetitive Pulse Generator)
-
LQ604 (Oil Breakdown Voltage Tester)
-
LQ603 (Insulating Oil Dielectric Loss Tester)
-
LQ602 (Transformer Frequency Response Analyzer)