LOM ( Loss of Mains )

How does it apply to our sseg systems and how does one do a LOM test.

You don’t have the equipment to do this kind of test :slight_smile:

Inverters monitors the voltage and the frequency. If it goes out of bounds, it will disconnect the grid. It may also use something called RoCoF, Rate of Change of Frequency, where it will disconnect if the frequency changes too quickly, even if it is within limits. These are called “passive measures”. In addition to this, it may also employ active measures, where it deliberately tries to push the frequency forward, which cannot succeed if the grid is on.

To test this, you need equipment whereby you can rapidly change the voltage or frequency that you feed the inverter with. The closest you will get, is a Variac (essentially an adjustable transformer).

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