Earthing re AC200P and or AC180

A question for Bluetti support.
I own an AC200P and an AC180 and will note the following differences; (Australia)

  1. The 200P has no grounding pole, the 180 does.
  2. The 200P has a charging brick converting its output to DC voltage, the 180 is inbuilt.
  3. The 240VAC cable to the 200P has 3 pins i.e. active, neutral and earth, the 180 charging cable has only 2 pins i.e active and neutral.

My first question is re the 200P when used in a household scenario i.e. power outage to run a 240VAC fridge/freezer.
Q1. Is there any way to give either earth or RCD protection should there be a fault with the fridge? i.e. Would connecting the charging brick to a grid earthed outlet give any earthing to the system through the earth pin of the cable? (with power switched off as an assumed outage of power has occurred.) Or, is it safe to use without earthing anything?

The 180’s primary use will be off grid caravan power i.e. microwave and possible augment the 200P during grid outages.
Q2. Similar scenario, different appliance, why provide an earth pole? Is it necessary to use it?

In both situations, given the house kitchen’s wooden floor and the caravan on rubber (tyres) there is no direct path to earth and I would rather not be the conductor… :)

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@BLUETTI_CARE can confirm to double check my answer here, Bluetti AC units are only grounded when in pass-through mode connected to the mains.

Grounding or not, adding a breaker like this is probably a good practice. The unit has an internal short protection, but not designed for your safety.
Adding one of those (it’s a 10mA breaker) adds a first layer of safety.

Thanks for the reply, This is the one I have, it conforms to AU supply and Standards. The benefits are the extra outlets (4 off) and the smaller profile of the plug top to the AC unit.
I guess the lack of the earth pin for the AC180 mains cable is why there is an earth pole as pass thru charging is not earthed.
AU mains supply codes use a neutral earth link which trips the mains power in the event of… so a leak from active to either earth or neutral will trip the RCD when pass thru charging,
For AC200P/180 outlets, a portable RCD is as you say better than nothing. I’m thinking that an earth pole to a peg in the ground is extra safety for the caravan, especially in wild weather, lol.

Please note that to get an electric shock from a floating grounded device you should touch both phases. By touching a single phase no current will pass through your body since that would not have any path to return back to one of the inverter phases by ground. So, an hazard is very unlikely to happen and that makes floating grounded devices like Bluetti relatively safe.
That means that any phase to ground fault on a fridge connected to a Bluetti will produce no effect by touching the fridge on a human body. And a double phase to ground fault will automatically throw a short circuit condition that will disable the Bluetti AC output (by probably damaging it) and so without creating any electrical hazard in both cases.
I also think it’s very important that the Bluetti AC input is always connected to a line protected by a RCD; in the case where Bluetti is providing supply to the fridge and also charging from AC and both phases are in by-pass from its input and output, any phase to ground fault on the fridge will eventually be detected by the RCD. That will disconnect the Bluetti which will enable its inverter output by floating both phases and thus avoiding the hazard.
Grounding any AC/DC inverting device is mostly useful to allow its filtering stage to release to ground any interferences or voltage spikes filtered out from the AC input.

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Thanks for the info, very well explained, what I was after :slight_smile:

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thanks for the explanation.
This should actually come from Bluetti :-)

Agreed, not the first time I have noted my post to Bluetti Support…