Factory Price SPD 20kA 1.5kV AC SPD surge protector spike suppressor surge protection device

SPD Surge Protective Devices are designed to protect against transient surge conditions. Large single surge events, such as lightning, can reach hundreds of thousands of volts and can cause immediate or intermittent equipment failure. However, lightning and utility power anomalies only account for 20% of transient surges. The remaining 80% of surge activity is produced internally. Although these surges may be smaller in magnitude, they occur more frequently and with continuous exposure can degrade sensitive electronic equipment within the facility.


A power surge is a brief overvoltage event that can damage electrical devices and is a common cause for the failure of electrical equipment. Surges can damage and reduce the lifespan of:

• Heating and Air Conditioning Systems
• Washers and Dryers
• Water Heaters
• Ranges & Refrigerators
• Lighting
• Entertainment Systems

Selection of SPD:
For a power distribution system, the main characteristics used to define the lightning protection system and select a SPD to protect an electrical installation in a building are:

• SPD
  • quantity of SPD
  • type
  • level of exposure to define the SPD's maximum discharge current Imax.
• Short circuit protection device
  • maximum discharge current Imax;
  • short-circuit current Isc at the point of installation.

The other characteristics for selection of a SPD are predefined for an electrical installation.

• number of poles in SPD;
• voltage protection level Up;
• operating voltage Uc.

This sub-section Design of the electrical installation protection system describes in greater detail the criteria for selection of the protection system according to the characteristics of the installation, the equipment to be protected and the environment.

Location and types of SPD:


Connection of SPD:
Connections of a SPD to the loads should be as short as possible in order to reduce the value of the voltage protection level (installed Up) on the terminals of the protected equipment.

The total length of SPD connections to the network and the earth terminal block should not exceed 50 cm.

                                    SPD in plastic enclosure                                                                             SPD in metal enclosure