What size RCCB and MCB for a Victron 12/250 inverter

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I have purchased a victron Pheonix 12/250 inverter and i can see from the wiring diagrams I need to connect the output to a RCCB and MCB before connecting to sockets. What the diagram doesnt say is what amperage the RCCB and MCB should be. Continual power from the inverter on the AC side is 200W and peak power of 400W. Any suggestions on amp sizes would be welcomed.

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The inverter will be unlikely to be able to clear (trip) any thermal magnetic breaker (standard kind) with a current rating of more than 1A. However, this is not really relevant, as the inverter will self protect and shut down in an overload situation.

Thus the smallest GFI (RCCB) you can buy can be used - probably a 16A one. You can also put a 2A MCB in series, but I would not bet on that ever tripping.

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Thanks @MikeD . What I am gathering form your answer is that the amperage output of the inverter is so low it wouldnt trip an RCD /MCB? My main concern was blowing the internal (non replaceable ) fuse in the inverter. Iā€™m planning to plug an extension cable into the ac outlet and then run low capacity items such as a laptop charger, DAB radio and dewalt powertool battery charger (not all at the same time :grinning_face_with_smiling_eyes: ) in my static caravan . They are all individually rated at less than the 200W continual power spec in the inverter manual so wouldnt be overloading the inverter. Would replacing the 13amp plug fuses for each item with a 5amp fuse offer greater protction for the inverter internal fuse or am I being over cautious? Apologie sbut new to this.

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Small Victron inverters usually shut down on overload, rather than destroying themselves, like the cheaper Chinese ones do. Iā€™m not aware of any output fuse in these inverters, though they usually do have DC input fuses, which are not impossible to replace - if you know what you are doing.

Generally with such a small inverter, I would not worry about output protection too much. The inverter will trip an RCCB on leakage current, though not on over-current. The tripping mechanism is different in the breaker, a ground fault has an electro-mechanical trip, rather than the thermal - magnetic trip used for over-current.

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