Created by: Glen Zhu | Updated Date: Aug 27, 2022
There are different types of SPD according to IEC/EN 61643-11, classified as follows:
| Direct lightning stroke | Indirect lightning stroke | Indirect lightning stroke |
IEC 61643-1:2005 | Class I test | Class II test | Class III test |
IEC 61643-11:2011 | Type 1; T1 | Type 2; T2 | Type 3; T3 |
EN 61643-11:2012 + A11:2018 | Type 1; T1 | Type 2; T2 | Type 3; T3 |
VDE 0675-6-11 | Class B | Class C | Class D |
Type of test wave | 10/350 μs | 8/20 μs | 1.2/50 μs + 8/20 μs |
Type 1 Surge Protective Device are intended for installation between the secondary of the service transformer and the line side of the service equipment overcurrent device, as well as the load side, including watt-hour meter socket enclosures, and are intended to be installed without an external overcurrent protective device.
Type 1 devices are dual-rated for Type 2 applications as well, providing the highest ratings available for installation at the service entrance.
Type 1 SPD can discharge lightning current with waveform 10/350 μs. It will be installed in the primary distribution board at the origin of the electrical installation.
A Type 1 SPD does not in itself offer the required protection level and must be used in conjunction with coordinated type 2 devices. An installation with a lightning protection system will require a Type 1 SPD.
Type 1 surge protection device is developed as the best solution available to protect service entrance at an industrial site, especially those with existing lightning protection systems or meshed cage applications.
Type 1 surge protection device is particularly useful in a high lightning density area where the risk of heavy surge current or even direct strike is high (eg: buildings equipped with lightning rods).
Type 1 SPD is characterized by a 10/350 µs lightning current waveform and installed at the load center’s main circuit breaker, e.g. main distribution board.
Type 1+2 surge protection device can protect all electrical installations against lightning strikes by discharging the current created from a lightning surge and keeping it from spreading to the equipment.
Type 1+2 SPD is characterized by a 10/350 µs and 8/20 µs lightning current waveform.
Type 1+2 surge protection device installed at the origin of the AC installation equipped with LPS.
Type 1+2 surge protection devices use Metal Oxide Varistor (MOV) and/or Gas Discharge Tube (GDT) circuits to protect electrical devices from spikes in alternating current power.
Type 1+2 SPD is designed to be connected in multi-pole configuration to protect single-phase, 3-phase and 3-phase+Neutral AC networks, and for TN-C, TN-S, TN-C-S TT, and IT power supply systems.
Type 2 Surge Protective Devices are intended for installation on the load side of the service equipment overcurrent device, including SPDs located at the branch panel.
Type 2 SPD can discharge 8/20 μs current wave, they can prevent the damage of transient overvoltage in the electrical installations and protects equipment connected to it.
It usually employs metal oxide varistor (MOV) technology. The device would normally be installed in sub-distribution boards and in the primary distribution board if there was no requirement for a type 1 device
Type 2 surge protection device is characterized by an 8/20 µs lightning current waveform.
Type 2 SPD is designed to be installed at the service entrance of low voltage systems or close to sensitive equipment to protect against transient overvoltages.
Type 2 surge protection device is for nominal working voltage (50/60Hz) Un = 120V 230V 400V ac applications, and for maximum continuous operating voltage (50/60Hz) Uc = 150V 275V 320V 385V 440V ac applications.
Type 2 SPD is generally installed in sub-distribution or machine control cabinets, for indoor use or fixed into a waterproof box for outdoor use.
Type 2+3 surge protection devices are normally installed right before the protected equipment.
Type 2+3 SPD is characterized by current waves (8/20 μs) and a combination of voltage waves (1.2/50 μs).
The technical parameters are usually nominal discharge current (8/20 μs) In and open-circuit voltage (1.2/50 μs) Uoc
These SPDs have a low discharge capacity. They must therefore only be installed as a supplement to Type 2 SPD and in the vicinity of sensitive loads.
Type 3 SPD is characterized by a combination of voltage waves (1.2/50 μs) and current waves (8/20 μs) and load current IL.
Type 3 surge protection devices are normally installed right before the protected equipment.
Type 3 SPD is generally installed near the protected load, to protect sensitive equipment for 24V 48V 60V 120V 230V, in coordination with Type 2 surge arrester installation head.
Arresters tested and found AC Type 3 surge protection devices are intended to be installed near sensitive equipment, in coordination with Type 2 surge arrester installation head.
Iimp – Impulse current of Type 1 SPDs with 10/350 μs waveform.
In – Norminal discharge current of Type 2 SPDs with 8/20 μs waveform.
Imax – Maximum discharge current of Type 2 SPDs with 8/20 μs waveform.
Uoc – Open-circuit voltage of Type 3 SPDs with a combination of voltage waves (1.2/50 μs).
Up – The residual voltage that is measured across the terminal of the SPD when In is applied.
Uc – The maximum voltage which may be continuously applied to the SPD without damage the SPD.
Copyright © 2010-2023 Wenzhou Arrester Electric Co., Ltd. All Rights Reserved. Privacy Policy
