Passive Protection Mechanism: SPDs rely on passive components (e.g., Metal Oxide Varistors (MOVs), gas discharge tubes) to suppress surges without requiring external power.
Self-Recovery Capability: For transient overvoltages (e.g., lightning strikes), SPDs
automatically reset to a high-impedance state after diverting the surge energy.
Key Limitations:
Cumulative Damage: Repeated high-energy surges degrade MOV performance (increased clamping voltage/slower response).
Sustained Overload Risk: Prolonged overvoltage (e.g., undetected voltage spikes) may cause overheating and failure.
The surge protector for sale is widely used in various electronic equipment, instruments and communication lines. They are suitable for AC 50/60HZ, rated voltage 220V/380V power supply systems (China), as well as various voltage systems in other countries. It is suitable for residential, tertiary and industrial fields, and can effectively protect power and signal systems from lightning strikes and other transient overvoltage surges1
| Failure Type | SPD Status Change | Post-Failure Functionality |
| Planned Outage (Maintenance) | No surge stress; SPD remains intact. | Fully operational |
| Transient Fault (Lightning) | SPD briefly conducts to dissipate energy, then self-resets. | Requires cumulative damage check |
Sustained Fault (Short-circuit/Overvoltage) | May trigger fuse tripping or SPD thermal damage. | Replacement needed |
Basic Type ( SPD module)
Single-stage MOV protection; remains functional post-outage if undamaged.
Risk : No fuse protection may lead to direct short-circuit during overload.
Backup-Protected Type/SSD (Circuit Breaker/Fuse Combo)
Fuse disconnects SPD during extreme surges.
Recovery: Requires manual fuse replacement/circuit breaker reset.
Smart Type (with Monitoring SPD):
Logs surge events but loses communication during prolonged outages.
Note: Core protection remains active if components are intact.
Parameter Mismatch
SPDs with maximum continuous operating voltage (Uc) lower than line voltage degrade faster.
Insufficient Insulation Coordination
Residual voltage post-surge may damage poorly insulated equipment.
Switch-On Surges
Power restoration spikes can fatally damage aged SPDs.
| Test Method | Procedure | Pass/Fail Criteria |
Visual Inspection | Check status LED (green=OK, red/off=failed) or color-changing window. | No indicator → Further testing |
| Multimeter Test | Measure MOV resistance (power off). | Significant drop/zero Ω = failed |
| Professional Evaluation | Use dedicated testers to verify clamping voltage/leakage current. | Parameters out of spec → Replace |
Regular Inspections
Mandatory after thunderstorms or major power disturbances.
Multi-Stage Protection
Deploy primary (first-level) SPD + secondary (cabinet) SPD + tertiary (outlet) SPD.
Parameter Matching
Ensure SPD’s Uc voltage and surge current rating (In/Imax) align with grid requirements.
Prompt Replacement
Replace failed SPDs or blown fuses immediately to avoid protection gaps.
Final Conclusion
Normal Conditions: SPDs self-recover after outages/transient faults.
Failure Conditions: Sustained overvoltage, fuse tripping, or parameter mismatch cause permanent failure.
Strategy: Combine visual checks + instrument testing, implement multi-stage protection, and ensure grid compatibility.
Appendix: SPD Lifecycle Management Flowchart
Power failure → Determine fault type (transient/sustained)
↓
Transient fault → SPD auto-resets → Log surge count → Periodic degradation checks
↓
Sustained fault → Inspect fuse/circuit breaker → Test SPD components → Replace damaged parts
Systematic maintenance ensures SPD reliability post-power failure.
What Are the Lightning Protection Systems Included in the Security Industry?March 13, 2023To know what lightning protection systems are available in the security industry, we must first understand the development and changes of the security industry. From the emphasis on "no AI, no se...viewEvaluating The Cost-Effectiveness Of Coaxial Surge Protection DevicesJanuary 10, 2024As the reliance on sophisticated electronic systems and communication networks grows, the need for robust surge protection becomes increasingly critical. Coaxial surge protection devices stand as the ...viewWhat is the Residual Voltage of the Surge Protector?March 23, 2022What is the residual voltage of the surge protector? When the SPD device is selected and adapted, its various parameters will be comprehensively considered, and a comprehensive selection will be made....viewThe Role of Lightning and Surge Protection Devices in Biogas PlantsJuly 4, 2024In modern biogas facilities, biogas, as a clean and renewable energy source, is being widely used globally. However, for biogas plants, which process organic materials and produce biogas, the safe ope...viewHow Does A Surge Protection Device Work?August 30, 20211. Learn what is a power surge before undersanding a surge protection deviceFirstly, you need to understand what a power surge is before understanding how a surge protection device works. When the vol...viewHow Do Telecommunications Surge Arresters Protect Telecom Facilities?July 3, 2024As global connectivity deepens, the role of telecommunications has become more important than ever. The security, connectivity, and continuity of telecom systems are crucial. Any telecom interruption ...view
EN
jp 
ko 
fr 
de 
es 
it 
ru 
pt 
ar 
vi 
th 
ro 
bg 
nl 
