Site Survey’s for Surge Protection

As a company we have always offered site surveys for complex electrical installations, but during the pandemic, when we couldn’t travel, we also found that we can offer an excellent service remotely, which helps us get to site faster. There as some situations, where an in-person site visit is still recommended, but for the majority of sites, a remote site visit is preferable.

  1. What type of situation would you recommend a company requests a site visit?


We can specify the surge protection required for the majority of sites with a simple phone call to our office, but sometimes site visits are recommended for complex electrical installations, usually where there will be multiple incomers, external lightning protection systems and installations where surge protection is being installed due to large amounts of previous damage.


  1. Where would you suggest using an on-site visit, rather than a remote assessment?


In person on-site visits would be recommended for very complex electrical installations, installations where internet connectivity may be an issue and also installations where data protection and safe guarding mean that video calling is prohibited.


  1. How does a site visit generally work?


Before arranging the appointment, whether in person or online, we will usually have an in-depth conversation with the electrician in charge, many sites we can specify without the need to actually come to site, so this is where we will usually establish the need for the site visit. Once the need has been established, we will work with the electrician to work out which method of survey will be the most beneficial.


Once on site, either in person or remotely, we will usually start the survey at the main incomer (or each main incomer individually, if it is a very large site) and assess the needs, while having discussions with the electrician regarding installation and location of devices. We will then proceed to look at sub distribution boards and finally specific equipment which may require individual protection. At this point we will have a discussion with the electrician to assess whether there are any additional things to consider for the installation, such as PV systems and EV chargers.


At the end of the visit, we will go away and produce a report with our findings and recommendations according to the latest regulations, which will be sent to the electrician as soon as possible.



  1. What tends to be the most common misunderstandings around the requirements of surge protection that you generally come across?


One of the most common misunderstandings is that surge protection can be installed at the main incomer to protect the entire installation, surge protection needs to be considered for the main incomer and then every distribution board over 10 meters from the incomer, to provide protection for the installation. If there is an external lightning protection system installed, this is even more important. This will mean that every cable that enters or leaves the installation requires a type 1 SPD installed to meet the requirements outlines in BS EN 62305.


  1. Are you finding there are common themes with the types of recommendations you are making (more surge protection required, for example)


I am finding that more thought is now being given to the protection of specific equipment pieces, such as fire alarms and data racks within installations. This is usually the sensitive equipment that is vital to the installation, in terms of safety and reliability.



  1. Give us an example of a recent/interesting visit you’ve made and how that went for all parties


My only in person site survey in recent times, was an extremely complex site, with multiple incomers, back up generators and external lightning protection systems.

The client had got in contact with us due to issues with an BMS panel that had been upgraded, due to the majority of the electrical services being underground, a remote session was not possible.

On visiting the site, it was quickly established that there were multiple external lightning protection systems, without adequate surge protection installed, but this was not what was causing the issues with the BMS systems.

On further discussions with the site engineers, I was told about the generator testing that happens regularly. It was my opinion that this was what was causing the damage to the BMS controls. It was discovered that the BMS systems had recently been upgraded, there were historically no issues with the old panels, but the generator testing did align with the damage that was seen on the newer panels.

As the newer controls were more sensitive, the same overvoltage was now causing damage. A plan for the rollout of site wide surge protection was then put in to place to help overcome any future issues with upgrading technology.

If you have any further questions, or would like to discuss a potential site visit, please do not hesitate to get in touch.

Kirsty Johnson MIET

01484 851 747