The brief
The substation's battery room still had its original lighting, a failing extract fan and an overloaded DC distribution board. The client's area classification put the space above the batteries in Zone 2, because hydrogen given off during charging collects at high level. Everything in that zone had to be suitable for it, and the substation could not lose its DC supply.
What we did
- Temporary supply: we connected temporary batteries and a charger so the protection and control systems stayed live throughout.
- Ventilation: a new Ex-rated extract fan at high level and a low-level fresh-air inlet, sized with the client's engineer to keep hydrogen well below its lower explosive limit.
- Lighting and controls: Ex-rated light fittings and fan controls, installed by CompEx certified electricians to BS EN 60079-14.
- DC distribution: a new DC board and cabling from the charger, then testing and changeover back from the temporary batteries.
- Inspection: an initial Ex inspection to BS EN 60079-17, with the records added to the client's portal.
The result
The battery room now matches its area classification, the ventilation is sized for the batteries installed, and the DC system has spare ways for future expansion. The client has the inspection records and certificates for the room in their portal, with the next inspection date already set.
