Small wind / Buyer questions
Electrical configuration
Does disconnecting the grid stop a wind turbine?
The short answer
Do not assume that it does. Grid-side disconnection stops a particular electrical power path; it does not by itself establish that the rotor is stationary or that all circuits are de-energized. The wind system needs its documented response to loss of the receiving grid, including electrical loading, stopping functions and any required auxiliary supplies. The applicable operating and isolation procedures belong to the actual installed equipment.
Track three states separately
| State | What it does not prove by itself |
|---|---|
| Grid export disconnected | That generator terminals and internal circuits are safe to access |
| Rotor visibly stopped | That stored electrical energy or other sources are absent |
| Controller display off | That the installation has completed its approved isolation process |
These distinctions prevent a purchasing description such as “automatic shutdown” from being interpreted as a complete maintenance procedure.
Ask what happens to incoming wind energy
When a converter cannot export, the control and protection system must manage the changed operating condition. Depending on the design, the response can involve load management, generation reduction or stopping functions. The equipment schedule should show what is actually supplied.
Permanent-magnet machines can generate voltage while rotating. Other components can also retain electrical energy or receive power from another source. A disconnected grid connection alone therefore cannot establish an electrically safe condition.
Make this part of handover, not an assumption
Request the model-specific operating states and the approved isolation and return-to-service procedures. Confirm who is trained and authorized to use them. The handover record should identify the actual turbine, controller, converter and auxiliary supply arrangement.
This page provides a distinction for selecting and documenting equipment. It is not a switch sequence or a DIY isolation instruction. MARSTON stopping and braking functions must be confirmed for the configuration quoted.
Use status messages with care
An alarm reading such as grid lost, converter stopped or brake applied names a state reported by a particular device. It is not automatically proof of every other condition needed for access or maintenance. The handover package should explain what each status confirms and which separate observations or approved procedures establish the overall installation state.
Sources
- ABB machine manual: permanent-magnet machine electrical hazards
- Morningstar: wind charging and input-protection considerations
Examples are illustrative. Confirm product-specific performance, compatibility and supply scope in the applicable documents.