Should/shouldn't an inverter be connected via an RCD?

[ChrisJEvans]

Did they already have an earth conductor on the overhead (as OGB implies, with ABC) - in which case it would be trivial - or did they have to add one or install a new overhead cable which is what I first imagined?

See photo below. No change to the supply, of two separate wires one insulated. All the houses in the road have overhead power. The house was built about 1928 near the centre of town (When the land was sold by the Duke of Norfolk in 1927 a covenant was included that any house built on the land must sell for at least £500!)

Not sure I understand what might have been wrong with the fridge in the first place, presumably you will have to fix it or get a new one now!

With just an earthing stake (Earth resistance about 80 ohms) the American style fridge freezer touch panel often stopped responding, it was new and they tried changing the controller boards and then the whole fridge freezer. The problem persisted but went away once the PME work was done.

At 60 ohms my earth spike is similar to your 70 so I would say that is not something to worry about, I would start at the fridge end. BTW the limit is 200 ohms not 180.

[ChrisJEvans]

Do remember if it’s an existing consumer unit, you should fit the same manufacturers equipment inside not other makes.

If you mean that the circuit breakers need to be compatible. I am aware that there are a lot of designs and you can't normally(ever) mix makes.

[AGT]

Yes, same make RCD, rcbo, mcb in the same consumer unit.

[Oldgreybeard]

Sound advice about Type Approval requiring the same manufacturer's components to be used for replacements. Only point I would add is that the manufacturers very often aren't the company with the brand name on the front. There are now groups of product brand names that are really the same manufacturer. This can make life a bit easier, as it may well mean being able to find a replacement/additional component that has an apparently different brand name, but is compatible and made by the same manufacturer.

In the case of one or two manufactures they have played a bit fast and loose with rebranding products, but those in the know will have a pretty good idea of who the true manufacturers are and whether parts are compatible. The major problem is with different manufacturers varying the relative height of the busbar terminals - can be very dodgy if trying to mix and match incompatible parts that end up distorting the bus bar or even not actually allowing the terminal to properly fasten to it.

[sharpener]

Not sure I understand what might have been wrong with the fridge in the first place, presumably you will have to fix it or get a new one now!

With just an earthing stake (Earth resistance about 80 ohms) the American style fridge freezer touch panel often stopped responding, it was new and they tried changing the controller boards and then the whole fridge freezer. The problem persisted but went away once the PME work was done.

A mystery then. But as it is under 200 ohms it complies with the CoP so you can connect your electrode to the MET, then you will have the best of both worlds

[marshman]

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