The BP25VT&BP25V&BPS12.5V is class I & class II (or T1+T2 ) SPD designed for low-voltage power system lightning current & surge protection, especially for location of high risk exposure or LPZ 0-2 building entrances ( IEC 62305-4) to against the damage from direct or close lightning strikes.

With built in PROSURGE high energy MOV, they ensures remarkable lightning current discharge capacity up to 12.5kA~25kA 10/350μs. The unique design of thermal protection provides quick thermal response and secure disconnection. They are ideal protection for environments with frequent switching operations or lightning strikes.

 

DIN-Rail, T1 SPD-BP25VT series

 A notable feature of BP25VT is low voltage protection level due to VT tech. It has long service life because of no leakage current and follow current.It can be applied in most electrical installation and provide better reliability and safety protection, and particularly suitable for system with permanent insulation monitoring.

 

• Class I + Class II/T1+T2 SPD per IEC/EN 61643-11
• TUV SUD certified 1P/2P/3P/4P SPD
• PROSURGE VT technology (GDT for NPE mode)
• Uc: 75Vac~750Vac
• Iimp: 25kA 10/350μs, 100kA for NPE mode
• In: 25kA 8/20μs,50kA for NPE mode
• No leakage current & follow current
• Higher TOV (Temporary Over-Voltage) withstanding performance
• High short-circuit current rating up to 50kArms
• Dual module redundancy for one pole SPD and dual fault indication […]
  

IEC 61643 is a series of international standards developed by the International Electrotechnical Commission (IEC). These standards define the requirements and testing methods for surge protective devices (SPDs) used in low-voltage power systems, telecommunications, and signal networks.

 

The purpose of these standards is to ensure the safety, performance, and reliability of SPDs when protecting electrical equipment from overvoltage surges caused by lightning strikes or switching operations.

 

About IEC/EN 61643：

 

IEC/EN 61643-11:

Low-voltage surge protective devices – Part 11: Surge protective devices connected to low-voltage power systems – Requirements and test methods

IEC/EN 61643-12:

Low-voltage surge protective devices – Part 12: Surge protective devices connected to low-voltage power systems – Selection and application principles

IEC/EN 61643-31：

Low-voltage surge protective devices – Part 31: Requirements and test methods for SPDs for photovoltaic installations

IEC/EN 61643-32：

Low-voltage surge protective devices – Part 32: Surge protective devices connected to the d.c. side of photovoltaic installations – Selection and application principles

IEC/EN 61643-21:

Low voltage surge protective devices – Part 21: Surge protective devices connected to telecommunications and signaling networks – Performance requirements and testing methods

IEC/EN 61643-22:

Low-voltage surge protective devices – Part 22: Surge protective devices connected to telecommunications and signalling networks – Selection and application principles

The SPD Types described below are in accordance (paraphrased from) with UL 1449

Third Edition, as follows:

 

Type 1 SPDs (Listed) – Permanently connected, hard-wired SPDs intended for installation between the secondary of the service transformer and the line side of the main service equipment overcurrent protective device, as well as the load side of the main service equipment.

Type 1 SPDs include watt-hour meter socket enclosure type SPDs. Being on the line side of the service disconnect where there are no overcurrent protective devices to protect an SPD, Type 1 SPDs must be listed without the use of an external overcurrent protective device. The Nominal Discharge Current Rating for Type 1 SPDs is either 10kA or 20kA.

 

Type 2 SPDs (Listed) – Permanently connected, hard-wired SPDs intended for

installation on the load side of the main service equipment overcurrent protective device.

These SPDs may also be installed at the main service equipment, but must be installed on the load side of the main service overcurrent protective device. Type 2 SPDs may or may not require an overcurrent protection device per their NRTL listing. If a specific overcurrent protection is required, the SPD’s NRTL listing file and labeling/instructions are required to note the size […]

When selecting between parallel or series connection methods for surge protectors (SPDs), the decision should be based on specific application scenarios and requirements. Both parallel and series connections are common configurations, each offering distinct advantages and suitable applications.

Parallel Connection
In a parallel configuration, multiple SPDs are connected simultaneously to the power lines of the protected equipment. This approach provides:

1.Higher current capacity and lower grounding resistance

2.Better distribution and mitigation of lightning surges

3.Enhanced overall lightning protection for the system

4.Redundancy and failover capability: If one SPD fails, others continue to protect the equipment.

Series Connection
In a series configuration, multiple SPDs are connected sequentially along the power lines. This method offers:

1.Higher voltage withstand capability for high-voltage scenarios

2.Cascaded protection, where each SPD handles a portion of the surge energy

Factors to Consider When Choosing Between Parallel and Series Connections

Applications for Parallel Connections

1.Low-voltage power systems
Parallel-connected SPDs are commonly used in low-voltage systems to share surge energy and protect equipment from lightning damage.

2.Communication systems
Multiple SPDs are often installed on telephone or network lines to shield communication devices.

3.Voltage-sensitive electronics
Parallel configurations protect sensitive equipment like computers and servers by optimizing surge energy distribution.

Applications for […]

Surge Protection Devices (SPDs) are critical components in safeguarding electrical systems from voltage spikes and surges. However, like any other device, SPDs can fail. Understanding the failure modes of SPD open-circuit and short-circuit—is essential for ensuring continuous protection and system reliability.

Open-Circuit Failure in SPDs

Open-circuit failure is a common mode of failure in SPDs, particularly those with varistors. This type of failure typically occurs due to the natural ageing process or thermal protection mechanisms. When an SPD reaches the end of its life, an internal disconnector is activated, rendering the SPD inoperative. This disconnector is designed to disable the SPD to prevent further damage.

In SPDs with gas discharge tubes, internal disconnectors (thermal protection) may also be used to protect against abnormal overheating caused by unexpected follow currents or surge currents. It’s important to note that thermal runaway, a common cause of failure in varistor-based SPDs, does not apply to SPDs with gas discharge tubes or encapsulated spark gaps.

A spark gap, another type of SPD, may fail in an open-circuit mode when it can no longer ignite an arc due to electrode wear or a faded electronic ignition circuit. In this state, the SPD becomes permanently open, leaving the system […]

impulse discharge current for class I test  imp

The impulse discharge current passing through the device under test (SPD) is defined by the crest value Iimp, the charge Q and the specific energy W/R. The impulse current shall show no polarity reversal and shall reach Iimp within 50 µs. The transfer of the charge Q shall occur within 5 ms and the specific energy W/R shall be dissipated within 5 ms.

The impulse duration shall not exceed 5 ms

Preferred values of impulse discharge current Iimp for class I SPD  Iimp：1，2，5，10， 12,5，20 and 25 kA

specific energy for class I test  W/R

energy dissipated by a unit resistance of 1 Ώ with the impulse discharge current Iimp

NOTE：This is equal to the time integral of the square of the current (W/R = ∫ i 2 d t).

Q (As) and W/R (kJ/W) for given values of Iimp (kA).

Q = Iimp × a，  where a = 5 × 10-4 s

W/R = Iimp2 x b，  where b = 2.5 × 10-4 s

The IEC 62305 standard, defines “protection levels” as specific categories of lightning protection systems, each designed to provide a […]

 

①High energy MOV technology

Voltage limiting type SPD per IEC 61643

High energy AC/DC MOV is employed for PROSURGE’s class I, Class II and Class III AC/DC/PV SPD with compact size.

 

Advantage of MOV (Metal oxide varistor)

*Higher lightning & surge current discharge capacity

*Wide voltage range to cover AC/DC/PV application

*Fast response

*Wide working temperature

*No follow current in case of surge events

*End of life through thermal runaway, make thermal protection possible

*Stable performance in a long period time.

*Compact size

*Not influenced by various environmental factors while  well encapsulated, especially suitable for application in higher altitude，offshore(e.g. offshore windfarms), dust, hot and moisture circumstances

 

The heat generated by a MOV in end-of-life conditions can be sufficient to cause dangerous overheating of the SPD and even cause the SPD to catch fire.

To keep the SPD and system protected safe, thermal protection is used in all PROSURGE’s MOV type SPD

 

②PROSURGE patented thermal protection technology

√ Fast response to abnormal heat of MOV body

√ Surge withstand coordination with the SPD surge rating

√ Fast disconnect and cutoff the circuit in case of SPD failure

 

③PROSURGE patented arc-extinguish  technology

Because of an arc between contact may happen while thermal disconnector open, even the arc current lasts for a short time, that […]

Photovoltaic power generation is another renewable clean energy besides wind power generation, and is widely used in various countries and regions. It has the characteristics of simple installation, scalability, stability, and long life. Lightning strikes and surges are also a major disaster for photovoltaic power generation systems. Prosurge provides a comprehensive and efficient lightning protection solution for photovoltaic power generation systems.

 

PV installation with an external LPS when the separation distances is maintained (excluding multi-earthed solar systems, such as PV power plants)

Class II/T2 PV SPD is suggested to used at DC side of invertor

 

PV installation with an external LPS when the separation distances is maintained (excluding multi-earthed solar systems, such as PV power plants)

Class II/T2 PV SPD is suggested to used at DC side of invertor

 

PV installation with an external LPS where the separation distances can not be maintained (including multi-earthed systems, such as PV power plants)

Class I/T1 PV SPD is suggested to used at DC side of invertor

Surge Protection Device (SPD) is an electronic device that provides safety protection for various electronic devices, instruments, and communication lines. It is suitable for power supply systems with AC 50/60Hz and rated voltage of 220V/380V. The types and structures of surge protectors vary according to their different uses, but they can generally be classified in the following ways:

一、 Classified by working principle

1. Voltage switch type: It is in a high impedance state when there is no instantaneous overvoltage, and suddenly changes to a low impedance state when a surge occurs, effectively diverting the surge current to ground and protecting the equipment from overvoltage damage. Commonly used nonlinear components include discharge gaps, gas discharge tubes, thyristors, etc.

 

2. Voltage limiting type: It exhibits a high impedance state when there is no surge, but as the surge current and voltage increase, the impedance will continuously decrease, limiting the voltage to a safe level. Its current voltage characteristics are strongly nonlinear, thus avoiding damage to equipment caused by overvoltage. Commonly used nonlinear components include zinc oxide, varistors, suppression diodes, avalanche diodes, etc.

 

3. Combination type: Combining voltage switch type and voltage limiting type SPDs together, it has both voltage switch function […]