Features of LSP (Lightening & Surge Protection) Devices
Explore the features of the Surge Protection Devices range:
- Devices have indicators to advise end of life of the device
- No resetting of SPD required, the excess voltage is quickly taken to earth, before the rest of the circuits are damaged
- The device meets the requirements of the IEC 61634-1 and EN 61643-11 standards
- The SPD enclosure can be fitted next to any exiting or new consumer unit of any brand where surge protection is required
Surge Protection Devices
SPDs provide protection from two forms of surge:-
LEMP - Lighting Electro Magnetic Pulse
SEMP - Switching Electro Magnetic Pulse
What are surges?
Surges are transients overvoltage or surge in short durations. Increasing in voltage measured between two or more conductors.
The increase in voltage will vary from a few volts to thousands of volts.
In this context short means anything from microseconds (millionths of a second) to a few milliseconds (thousandths of a second) in duration.
This voltage exists between two or more conductors.
For a mains power supply, these conductors would be the line, neutral and earth.
These can be created from atmospheric (lightning) or switching (Industrial) occurrences.
The consequences of a surge
Without adequate protection the greatest consequence is a risk to human life, particularly in circumstances where medical equipment is involved and could be damaged. Medical equipment includes MRI Machine, CT Scan Machine, Anesthesia Machine etc.
Secondly, there is the potential downtime in production e.g. in a workshop, retail outlet or office. Which Includes Servo Drive, VFD, SMPS,PLC,HMI, Router, Modem, Server etc.
‘Transient overvoltage’, is technically and descriptively the best terminology. However, transients are also referred to as surges, spikes and glitches.
Types of Surge Protection Devices (SPD)
Installation as defined in the standard is simple enough, the device is connected with cables to and from the unit no longer than a metre in total, and a short path to earth will ensure the effective discharge of the surge to earth.
Type 1 SPD
The Type 1 SPD is recommended in the specific case of service-sector and industrial buildings, protected by a lightning protection system or a meshed cage. It protects electrical installations against direct lightning strokes. It can discharge the back-current from lightning spreading from the earth conductor to the network conductors.
Type 1 SPD is characterized by a 10/350 µs current wave.
Type 2 SPD
The Type 2 SPD is the main protection system for all low voltage electrical installations. Installed in each electrical switchboard, it prevents the spread of overvoltage's in the electrical installations and protects the loads.
Type 2 SPD is characterized by an 8/20 µs current wave.
Type 3 SPD
These SPDs have a low discharge capacity. They must therefore mandatorily 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).
Note: If a Type 2 SPD is installed and cable lengths are less than 10m, then there is no longer a requirement to fit Type 3 surge protected extension leads. If greater than 10m then type 3 surge protection should be fitted.