The electrical installation in my house was re-wired about 20-odd years ago and appears still to be in good order. The energy supply company replaced the old black meter by a digital 'white box' some years ago, but that has been the only change.
All circuits are supplied through an 8-way Wylex consumer unit with re-wirable fuses. There is no RCD in the CU. However there is a separate, 60A black trip switch (known as a VOELCD I believe?) in the tails between the meter and the CU. From what I have been able to gather about the history of the installation, this had been inserted into the previous installation at least 30 years ago, then retained when that installation was replaced some year later.
There is an earth wire from the VOELCD to an earth rod under the floor, another earth wire from the VOELCD to the earth rail in the CU, and a third earth wire from the CU to the earth rod. There is NO earth connection to the incoming undergound supply cable.
I know that the VOELCD does work - it tripped last year when there was a short in an electric kettle - but I wonder if it is necessary/prudent to replace it now by a modern RCD? If so, to avoid more extensive disruption to the CU etc, can this be done simply by replacing it with a 'stand-alone' RCD (plus any necessary adjustment to the earth wiring). I was thinking of something on the lines of the 63A RCD-only Wylex Shower Unit, which is about the same physical size and layout as the VOELCD and would fit the space easily.
Your advice please?
All circuits are supplied through an 8-way Wylex consumer unit with re-wirable fuses. There is no RCD in the CU. However there is a separate, 60A black trip switch (known as a VOELCD I believe?) in the tails between the meter and the CU. From what I have been able to gather about the history of the installation, this had been inserted into the previous installation at least 30 years ago, then retained when that installation was replaced some year later.
There is an earth wire from the VOELCD to an earth rod under the floor, another earth wire from the VOELCD to the earth rail in the CU, and a third earth wire from the CU to the earth rod. There is NO earth connection to the incoming undergound supply cable.
I know that the VOELCD does work - it tripped last year when there was a short in an electric kettle - but I wonder if it is necessary/prudent to replace it now by a modern RCD? If so, to avoid more extensive disruption to the CU etc, can this be done simply by replacing it with a 'stand-alone' RCD (plus any necessary adjustment to the earth wiring). I was thinking of something on the lines of the 63A RCD-only Wylex Shower Unit, which is about the same physical size and layout as the VOELCD and would fit the space easily.
Your advice please?