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How to define the part number of a surge protection device?

To Define the reference of a surge arrestor you must consider the following

NOTE : Our Surge Arrestors are for protection against Lightning Strikes only, not general transients
  1. Do you have a lightning rod fitted on the building
  2. How far is the building from the main transmission lines
  3. Is the surge required a single phase or 3 phase?
  4. What is the PSCC (Prospetive Shot Circuit Current) measured at the point of install
  5. Which type of Surge Arrestor do you requrie , e.g. Type 1 , Type 2 or Type 3
  6. What are the earthing arrangements of the installation (e.g. TNC-S , TN-S , IT or TT)

Below is a summary of the differences between types of surge arrestors

Type 1 - direct lightning strike on the building (10/350 micro second waveform)
Type 2 - Impacts near the building or on the network (8/20 micro second waveform)
Type 3 - Protection near to the sensitive loads (1.2/50 micro second waveform)

We offer type 1+2 Combined Surge Arrestors that can be fixed or withdrawable type

Fixed - When the surge arrestor is blown the whole unit needs replacing
Withdrawble - The surge arrestor has cartridges that can be replaced when they are blown

Type 2 Surge Arrestors can be PRD65, PRD40, PRD20 and PRD8 - the numbers refer to the kA rating required (this can change depending on whether it is a low or high risk area)ghting
PRD65 for high risk if the buiding is near by a tall tree or a tall building with lighting rods within 100m.
PRD40 for medium risk if the building is nearby a transmission line
PRD20 for low risk environment
PRD8 used as a seconary protection incase of sensitive loads further than 10m from main SPD

Protective devices for the above models are attached Protective Devices for iPRD.bmp (In the UK we commercialise the iC60H range and the NSX100F/N types of MCCB's) 

Surge Arrestor Kits

For surge protection on Distribution Boards we offer a kit which includes the following
  • Enclousre
  • Type 2 Surge arrestor
  • Distributed Neutral kit
  • 4 pole MCB to suit the surge you select
  • Cabling to connect all devices together
Part number for the kits are below

3 phase + Neutral

PRD3PN65r - 65kA Type 2 Surge Arrestor with remote signal to show when cartridges need replacing
PRD3PN40 - 40A Type 2 Surge Arrestor
​PRD3PN40r - 40kA Type 2 Surge Arrestor with remote signal to show when cartridges need replacing
​PRD3PN8 - 8kA Type 2 Surge Arrestor

Single Phase + Neutral

PRD1PN40 - 40kA Type 2 Surge Arrestor
PRD1PN20r - 20kA Type 2 Surge Arrestor with remote signal to show when cartridges need replacing
PRD1PN8 - 8kA Type 2 Surge Arrestor

For the complete offer see SE8863__4_Surge_Protection.pdf 

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