A metal fusebox designed for use on electric heating installations. Pictures provided by Owain Carter.
This would be used for the normal circuits such as lighting, sockets and cooker. The right fuseway will be one of the slightly different types which can accept fuses rated above 30A - typically used for a single high power circuit.
The lower sections are for an immersion heater and night storage heaters - each has it's own switch. These would be connected to a separate timed supply, so that they only operate at off-peak times (typically a 7 hour period after 11pm).
Inside, the components are the same as used in the more usual Wylex boards. Incoming power connects to the top of each switch, outgoing circuits to the top of each fuse, neutrals to the block to the left of the switch, and a single earth bar for the whole installation at the top left of the cabinet.
This installation has been modified, as the top right 30A fuse has nothing connected, and the left fuseway on the lower set of 3 has a circuit connected with no fuse (a blank plate is fitted instead).
Another more recent MEM fusebox can be seen to the top right of the picture. This was probably installed to provide additional circuits for storage heaters.
The circuit wiring enters through a single large hole in the back panel. The presence of the 'chocblock' type connector suggests some modifications have been made.
Note also the uninsulated bare copper earth wires in close proximity to the live busbar above.