Standby set with automatic mains failure panel
A generating set wired behind a panel that senses mains loss, starts the engine, transfers the load and hands it back when the supply returns. It spends almost all its life not running, which shapes what fails on it.
Features
- Transfer is normally break-before-make with a defined dead time, so any load that cannot tolerate that gap needs an uninterruptible supply of its own.
- The panel decides the installation: mains sensing thresholds, start delay, transfer time, cool-down and return delay are all set values, not fixed properties.
- Weekly or monthly automatic test runs are standard, and the test should be on load, because an off-load test proves almost nothing.
- Battery, charger and coolant heater are energised permanently and are the components most likely to have failed when the set is called.
- Fuel sitting in a tank for months degrades and grows water, so a polishing or draw-off regime belongs in the maintenance plan.
Specifications
| Figure | Typical range | Unit | Why it matters |
|---|---|---|---|
| Standby output | 80 - 1 500 | kVA | The duty rating for this configuration. |
| Transfer time | 8 - 15 | s | Defines the dead time seen by the load. |
| Automatic test run interval | weekly / monthly | The only thing that proves the set will start. | |
| Coolant heater rating | 1.0 - 3.0 | kW | Governs start reliability in a cold plant room. |
| Starting battery capacity | 80 - 200 | Ah | The single commonest cause of a failed start. |