Electrotechnically instructed person (EiP)
Works exclusively under the direction and supervision of an electrical specialist in a voltage-free state (battery safety) of the battery systems or low-voltage modules or carries out non-electrical work in the vicinity (safe distance) of active parts.

Electrical specialist for defined tasks (ESfdt)
Carry out standardized electrical work independently, including disconnection and commissioning (e.g. low-voltage switchgear, inverters). However, with the restriction: Only according to work instructions (checklist). Live line work is only permitted with the additional qualification LLW and only according to precise specifications.

Electrical specialist (ES)
The electrical specialist carries out work independently, including troubleshooting. Can and may also independently select suitable work equipment. Suitable maintenance of professional competence must be ensured (e.g. ES maintenance course). The corresponding additional qualification is required for live line work. Further training as a battery specialist is possible.

Live line work (LLW) on battery systems
Additional qualification for ES and ESfdt for authorization to work under voltage, if required.
This is not uncommon for systems such as battery systems, as a battery system always supplies voltage due to its electrochemistry.

Chief responsible electrical specialist (CRES)
The chief responsible electrical specialist assumes corporate responsibility for electrical safety. Depending on their area of responsibility, this may relate to the design of battery systems, electrical battery safety or their operation.