inside inverter

I have a new 2 kW inverter connected to my 12 V lessure battery. As soon as I had plugged a 1 kW appliance into it it blew. Pic shows a component that looks like it's melted. I'm very limited with electronics knowledge, can anyone guess why this could be happening. This is the second inverter to blow in the first try.

Many thanks.

  • \$\begingroup\$ Someone was being very optimistic about the power rating of your inverter. 2 kW @ 12 V is WAY more than 40 (or even 80) amps. That must be a very short-term peak rating, not a continuous rating, which will be more on the order of 400-500 W. \$\endgroup\$ – Dave Tweed May 31 at 21:51
  • \$\begingroup\$ what was the appliance? not something like a vacuum cleaner or hand-held circular saw by any chance? they way more than their run current when starting up. \$\endgroup\$ – Jasen Jun 1 at 9:32

enter image description hereThe melted component is a fuse, so it's likely that it has done what it's meant to do and blown before anything expensive fails. It should just pull up with pliers, but it looks like it has melted to its neighbor, so might need some effort separating. It likely has 1/4" blades that are pushed into receptacles on the board underneath. The fusible element itself is in the middle of the body, under the "40" designation, which is its current rating in amps.

  • \$\begingroup\$ Thank you Phil. Any idea why the fuse would have blown? Apart from the obvious too many amps :) \$\endgroup\$ – Nathan May 31 at 19:14
  • \$\begingroup\$ What was the appliance? Anything with a motor in would likely have a startup current considerably higher than the continuous rating. \$\endgroup\$ – Phil G May 31 at 19:16
  • \$\begingroup\$ Ah I see. It was a hand held steamer. Would that have a high startup current do you think? Should I look into replacing the current fuse with a higher rated one or would that be unwise? \$\endgroup\$ – Nathan May 31 at 19:19
  • \$\begingroup\$ That shouldn't have been excessive. Don't use a larger fuse, the ones there are sized to be the first component in the circuit to fail, there may not be enough margin in the other components to survive a higher load - the output of the inverter is switched using transistors (generally FETs) that will tolerate some overload, but also have a small thermal mass, so they can pop in a fraction of a second on overload. Replace the fuse and check that the inverter is still working with a smaller load, it may be that the fuse has failed due to some other component failing first. \$\endgroup\$ – Phil G May 31 at 19:24
  • \$\begingroup\$ Thanks for you help and advice Phil, very much appreciated! \$\endgroup\$ – Nathan May 31 at 19:26

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