Side-by-side reference

Understand the difference.

Compare the meaning, drawing context and source references of two entries. A similar graphic or shared abbreviation does not establish equivalence.

First referenceCompare with

CCU

IEC

Cooker control unit

A cooker control unit is a high-current double-pole switch, sometimes with an auxiliary socket outlet, that controls and isolates a fixed cooker or hob. Plan legends usually draw a switch box with the letters CCU or a cooker mark, placed within reach of the appliance but not above the hob.

Drawing use: GA
Application: Installation & communications
Reference family: IEC
Form evidence: Cooker control unit. IEC 60617 installation-plan style (architectural and topographical installation symbols); independently drawn, not certified IEC geometry or a database identifier.

A distinction that matters

A general isolator mark has no auxiliary outlet and is not tied to a cooking appliance; the cooker control unit is a dedicated appliance accessory.

Full reference

ISO

IEC

Local isolator plan mark

Local isolators are placed within sight of motors, air-conditioning units, pumps and fans so maintenance staff can isolate and lock the supply. Plans draw a small switch box with an isolation mark or the letters ISO beside the equipment it serves, sometimes with a lock indication.

Drawing use: GA
Application: Installation & communications
Reference family: IEC
Form evidence: Isolating switch, installation plan. IEC 60617 installation-plan style (architectural and topographical installation symbols); independently drawn, not certified IEC geometry or a database identifier.

A distinction that matters

A switched socket outlet is not an isolator; this plan mark designates an isolation-rated device.

Full reference

Original educational previews. Follow the source references on each full entry for the appropriate standard or selected product.