IEC TS 61970-555:2016(E) specifies a Component Interface Specification (CIS) for Energy Management Systems Application Program Interfaces (EMS-API). This part specifies the format and rules for exchanging modelling information based upon the CIM. It uses the CIM/E Schema as the meta-model framework for constructing CIM/E documents of power system modelling information. The style of these documents is called CIM/E format. CIM/E is suitable for use in online model exchange of power system applications.