Dating Old Electrics
Some dates - but may contain errors, and sometimes things did get installed later than they should strictly have been.
Cables
- Lead sheath cable: some say before 1948, some say it was still being installed in the 50s. On farms it was used later than this.
- TRS (Tough Rubber Sheath) 1945-1962
- Capothene (rubber insulated, polythene sheath): 1952-1960
- Ashothene cable: 1952 - 1960
- PVC inner PVC outer T&E style cables with no cpc (no earth wire) (lighting circuits): 1955-1966
- Imperial PVC cables: 1955 - 1971
- 2.5mm PVC/PVC T&E with 1mm cpc: 1971 - 1981
- Twin twisted flexible cords: before 1977
- Rubber/PVC mix T&E cable: 1958 to 1961
- CMA (Cable manufacturers association) cable: ceased in the 1940s
- Non-association (Nonazo) cable: pre apx 1948
- Aluminium cable:
- Copper clad Aluminium cable:
- Maconite cable (very distinctive O--O shape): pre WW2
Earth wire in cables
- Separate bare copper earth wires run alongside twin cable:
- Black earth conductors: before 1966
- Green protective sleeving: before 1977
- Green & yellow earth sleeving: 1971 onwards
- Earth wires just twisted together at junctions:
Cabling methods
- Cables fixed to wall with ceramic cleats (small plates with grooves to hold the wire): pre WW1
- Wooden trunking:
- Rubber singles in steel trunking:
- Uninsulated metal cable clips/cleats:
Main earth bonding
- No main equiptential bonding conductor: before 1966
- 2.5mm main equipotential bonding conductors: 1971-1972
- 6mm main equipotential bonding conductors: 1966 - 1983
- 10mm main equipotential bonding conductors: post 1983
Fuseboards
- ELCB (Voltage operated circuit breaker): pre 1981
- Double pole fused switchgear on ac Installations: pre 1955
- Wood backed Wylex fuseboxes: still being installed in 1983
- Slate fuseboard with bare screws for fusewire links: in use in late 1800s, obsolete by the 1930s
- Wooden fusebox with wooden lid: standard in 1930s
- non-EEBAD installs (local earth rod but no ELCB or RCD): pre 1955
Sockets
- Accessories mounted on wooden pattress blocks: before 1966
- Round pin socket outlets: mostly before 1955, but sometimes used much later
- Square pin 13A sockets: post 1945 - may be on older wiring though
- 2 pin 5A sockets:
- No sockets upstairs:
- Sockets with no shutters: