We no longer install meters in this configuration, which dates back to 1999.
It typically consists of:
A master meter. This is usually at the front of the property or building complex. It records all water that passes through the units or dwellings where water is connected.
Subsidiary or sub meters. These are private meters connected to the master meter. They are usually further down the line, outside the unit or dwelling they supply. They record water use for that dwelling.
Some properties have unique arrangements. For instance, the line between the master meter and the sub meters may feed a communal tap, pool, irrigation system or carport.