Your main LV switchboard is the heart of your electrical installation. Everything downstream depends on it, yet it’s often the piece of kit that gets looked at least. So how often should it be maintained, and what does maintenance involve?
How often?
There isn’t one interval that fits every site. The starting point is the switchgear manufacturer’s recommendations, adjusted for how critical the supply is and the environment it’s in. As a broad guide:
- Critical sites such as data centres, hospitals and continuous manufacturing: typically annually, often alongside thermal imaging.
- General commercial and industrial sites: commonly every one to three years, depending on the manufacturer’s guidance and the switchgear’s condition.
- Dusty, damp or high-load environments: more often than the standard interval.
Air circuit breakers (ACBs) also need operating periodically. A breaker that sits closed for years can stick when it’s finally asked to trip.
What planned maintenance involves
- A planned shutdown, usually out of hours, agreed well in advance.
- Visual inspection and cleaning of the switchboard and busbar chambers.
- Torque checks on busbar and cable connections.
- Servicing ACBs: mechanism, contacts and arc chutes inspected, cleaned and lubricated.
- Testing trip units and protection settings, often by secondary injection.
- Insulation resistance and contact resistance testing.
- A full report of what was found, what was done and anything that needs attention.
Warning signs yours is overdue
- No record of when it was last serviced.
- Breakers that haven’t been operated in years.
- Hot spots on a thermal imaging survey.
- Unexplained nuisance tripping.
- Signs of overheating, discolouration or a burning smell in the switchroom.
Thermal imaging in between
A thermographic survey under load is a quick, non-intrusive way to keep an eye on your switchgear between shutdowns. It picks up loose connections and overloaded components before they fail, and many insurers ask for one annually.
We carry out LV switchgear maintenance, ACB and MCCB servicing and thermal imaging across London and the South East, with shutdowns planned around your site. Request a free quote or call us on 01525 582582.
