Recent new DB’s installed, the sparkie followed his training, i.e. lights and geyser before RCD.
Saw it, whilst he was busy, and asked him to put the geyser and lights after the RCD please.
But nuisance tripping’s, he said.
Yes, I’m aware. If that starts happening one day then I will know that something is not right. I will then identify which circuit and we will sort it.
As of Today:
3 x Eskom and 3 x Critical Load DB’s in this house.
Each of the 6 DB’s have a 63a RCD’s for my protection.
2 newer DB’s, all are wired after the RCD.
Main Eskom DB from the street, when we do the entire house CoC early 2025, the geysers will be moved to after RCD too.
True, but this is one of those cases where, while electricity takes the shortest path… not all of it does that. So when you have an element that has corroded to the point that it is making electrical contact with the water, and the water not being entirely sterile, then the vast majority of the current will of course take the shortest route to the metal tank (which is grounded), but a small amount, probably in the <1mA range… is going via the copper pipe and the water through the human being in the shower…
Well if you change anything on your installation after the new regulations, you would have to change it to be compliant anyway. But apart from that, your geyser and pipes should be hard-strapped to earth so a trickle should not be possible unless you also have another fault.
From what I recall the regulations changed for the safety of plumbers, not the end-user… (after some grim stories)
Not a scientific poll but in my experience since ±2018 with various Installation Electricians, now and then even a Master Electrician or two, the ones that can haul out the latest regulation book released (onsite on request), them having been on the update course, maybe 1 out of ±20. It is not cheap to get the book and do the course.
What then follows, the interpretation of what that latest book says, when it is not absolutely clear.
Hence I read all these post with attention, and where I’m unsure, ask the people I trust off forum, for their opinion.
Then I present that knowledge of how I want it done to the sparkie doing the work, and the good ones, they make work of that information.
The ones who don’t, argue with no book in hand, have asked one or two to leave the premises too.
Since this thread started, I have on three installations, installed an earth leakage on the stove and geyser, even though there were none to begin with. Left lights on the the no earth leakage circuits.
Loads with a poor load factor, like florescent lights, large motors, or even a large number of PCs can cause nuisance tripping. This is not a fault - it is a real lag in phase current, which the RCD detects and trips on.
So it is not always something that can be ‘fixed’.
How would that work? An RCD just checks that the current on neutral is the same as the current on live.
In modern houses the biggest cause of nuisance trips are the class Y caps in SMPSs that connect to earth. (and surge protectors, that have essentially the same arrangement.) The solution is RCBOs.
RCBO stands for Residual Current Circuit Breaker with Overcurrent Protection. It’s a safety device that protects electrical circuits from overloading, short-circuiting, and earth leakage currents. RCBOs are a vital component of electrical systems and are installed in consumer boards or fuse boards.
An RCBO protects electrical equipment from two types of faults; residual current and over current. Residual current, or Earth leakage as it can sometimes be referred to, is when there is a break in the circuit that could be caused by faulty electrical wiring or if the wire is accidentally cut.
