It is designed to control electric motors of transformer air cooling fans.
Circuit diagram of automatic blast control cabinet SD-2 provides:
- local control of blowing from cabinet panel;
- remote control of blowing from the control panel;
- automatic control by transformer load current;
- automatic control by temperature of upper layers of oil;
- Automatic blast control cabinet SD-2 is a welded box with a lockable door.
Inside the SHD-2 cabinet is fixed the automation panel with control devices located on it. The automation panel is fastened inside the cabinet to the back wall. The panel contains hardware and output terminals.
When the temperature of the upper layers of oil rises above +55ºC, the transformer cooling system is activated. When the temperature drops further below +50ºC, the cooling system is switched off.
The cooling system is also activated when the load current exceeds 1.05 of the rated current.