So a carpenter was busy here at my house installing a new door in a steel frame. The door had to be turned around so he had to drill new holes in the frame.
While he was busy, my power just went off. No breakers tripped on either the main DB or the sub DB. However, my MPII just had its “Overload” light on. I had to switch it off, bypass it and switch it back on.
Then I received the emails from VRM "Overload L1 on VE.Bus.
Does anyone know what could have caused it? My grid was on at the time so my inverter couldn’t have been “overloaded”. There was also basically no loads on in the house at the time either.
Could this be due to a short on a circuit sitting behind the inverter? (Given that no breakers tripped)
Pretty sure my configurations are correct. Its ran perfectly for months. I’m more suspecting that there was a short on the MPII’s output. Not sure why the inverter would go into overload before a break on the DB would trip though, but electricity isn’t my strong suit…
With a dead short on the output, it is possible that the Multi can shut down on overload without a breaker tripping. The breaker needs 5 times it’s rating to trip instantaneously, while a 3kVA multi will probably struggle to do 30A under a dead short, and will shut down in under a second.
In fact, that is how I test overload conditions. I literally have a 3-point plug with an old AC/DC breaker wired directly across the live and neutral. It doesn’t make nearly as big a spark as you might think, especially on the smaller inverters. And they shut down pretty quickly.
Ah so that might well be happened. I do have a 5kVA, but maybe when it comes to dead shorts it doesn’t matter that much. Pretty sure it was the drill the carpenter was busy with… I’m going to test it again this weekend. On the one plug circuit not on the inverter.