The most damaging issue that can occur for a poorly maintained LV switchboard is a sudden component failure and power outage. Regular inspections and testing, including thermal-imaging can help to identify early problems including components that could require replacements and operating conditions that need addressing.
One of the most important aspects of regular LV switchboard maintenance is the establishment and update of specific maintenance records and registers. Not only should these record test results and notices but also the future maintenance schedule. Each switchboard record should include nameplate data, major components, manuals, renewable and consumable parts lists, drawings and notices.
LV switchboards should undergo regular test and inspection. These tests can include insulation resistance tests and high potential tests. Following a service inspection and before returning an LV switchboard back into service, its operation should be finally checked.
When carrying out switchboard maintenance it is important for the maintenance engineer to have a suitable supply of parts and that the right test gear is available. The engineer should have spare parts covering vital operating components. A manufacturer’s spares list may provide useful information for this.
There are also safety considerations. Firstly only certified, authorised and trained engineers should be permitted to inspect and test the switchboard. The engineer should be electrically competent and certified to work on LV electrical supplies as application to the country of operation and even industry association.
Whilst the routine for LV switchboard will vary between manufacturers, one of the most important safety aspects is to de-energise the board, test for potential and earth before carrying out any internal inspections. Breakers should be open as these can store mechanical energy. The breakers themselves may also have their own inspection and maintenance requirements.
How often LV switchboards are tested and inspected is very much down to country regulations and company practices. It is generally good practice to inspect switchboards every three to six months from commissioning date with annual preventative maintenance test program. These times will vary depending on the conditions the switchboard is to operate in. Adjustments may have to be made for high humidity and ambient, corrosive atmospheres, excessive dirt and dust, high duty, frequent interruptions and faults, inspection histories and the age of the LV switchboard itself.
B&S Group is one of the UK’s leading specialist manufacturers of LV switchboard. Our subsidiary company B&S Technical Services provides a complete range of on-site test, inspection and maintenance services for LV switchboards and related power distribution products.