RCD Protection Question......

[Spoon]

PS I can't see how anyone can get tingles for a Class II insulated lawnmower wearing suitable protective gloves, footwear, eye & ear protection, hi vis vest & safety helmet?

Done be silly.... You don't need all of that stuff, just a faraday suit..... oh.. and some wellies..

 

[Deleted member 26818]

As Murdoch says. Its worth getting the rcd tested electrically and also get the earthing checked. A rcd will not operate correctly if the earthing is not adequate, since it measures an imbalance via "earth leakage" current.

Sorry but that is just not true.
An RCD will operate if there is no earthing at all.
In fact most electrical garden equipment uses 2 core flex with no CPC.

 

[Deleted member 26818]

Many years ago, I attached active RCD plugs to all my tools which could possibly cut through the power cord.
Whenever I use one of the tools,I would test the RCD plug.
That way I would not be relying on any RCD or RCBO installed in the CU that may or may not have had the test button pressed.
Personally I believe individual RCD sockets are safer than a single RCD/RCBO protecting the circuit, as they are more likely to be tested at each use than any in a CU.

 

[davesparks]

A rcd will not operate correctly if the earthing is not adequate, since it measures an imbalance via "earth leakage" current.

An RCD detects imbalance between line conductors or between line conductors and neutral and trips once a threshold has been exceeded. It doesn’t measure anything

 

[HandySparks]

When you say you tested the RCD you mean the ‘T’ button on the RCD? If so, it only tests it mechanically.

Not true. On every RCD that I'm aware of, it's an electrical test. Done using a fixed resistor between incoming line and outgoing neutral (or vice versa) to create the current imbalance required. It's likely to be at a higher current level than the rated trip differential current, so it's only an indication that the RCD is still functional rather than an accurate test of sensitivity.