Do EV charge points have RCDs in or Not??? RCDs tripping everywhere?!?! 

That's interesting how different these systems work. In 2017 I installed a wall charger for my mum. The manufacturer also for a demanded type A RCD in the supply dedicated for that circuit and the charger offers the DC protection internally. It indicates an error (three red LEDs, it has no fancy display) and the type A RCD trips. Even with a DC fault. It probably creates a leakage current to trip the local RCD. And also uses this system to isolate in case of other errors like one of the three phases is missing, too high or too low voltages between the phases or between the phases and the neutral. I actually had the missing line error once. The heat pump of the car was running, and the door was opened, so the heat pump was increasing and tripping the selective main circuit breaker of one line in the house (50A). The 32A C32A didn't trip, the 30mA type A RCD did trip then. The 50A Neozed was not blown, but the selective 50A main circuit breaker before the meter tripped. These things are quite sensitive sometimes on some occasions. They are rated to be selective to gG/gL curve fuses of the same current rating, and these should actually blow first before that MCB trips. These breakers became popular since the regulations now demand that there must be a measure before the meter that an electric layperson can isolate the whole installation before (!!) the meter. So we now got these before the meter, and the regular isolator switch after the meter. And more upstream are still 63A NH fuses in the service head.

Really starting to appreciate your content lately mate, keep up the good work👍

Great video thanks Mark.

Interesting video Mark. I think this will help people think about EVSE and start those healthy discussions.

I've fit ICS's gear and have split the tails and fit a surge protected board with a type a 32 amp rcbo. The ICS has an electronic RCD that acts like a time delayed RCD, add this to the fact that the RDCDD is in circuit I really do rate this device.

Interesting 👍

The RCD protection in the charger does NOT protect the cable from the distribution panel (CU) to the charger. Accordingly, there are three reasons why you might need a second RCD before the charger: 1. To make up for any lack of protection in the charger 2. To protect everything in the installation in the circuit from the distribution panel to the charger 3. As a backup in case the RCD in the charger fails.

Residual Current tested a Rolec EV Charger a while back and it looked like that had a separate built in RCD that then fed into their bespoke controller that also covered AC and DC RCD protection, but he could only get the controller to trip on the RCD testing from the EV Charger outlet, he didn't do as much testing as you though.

Good 👍

You always explain these things well Mark I get what you say now about the RCD not being in the unit and at the supply. Like the way, you reach out to others (manufacturers) to give you feedback. I put your name forward last year for an award for the work with 121 something Paul Meadham E5 was involved in never heard anything after that did you get it?

My understanding, is a DP 30mA RCD has to be installed at source point (Id call that upstream?) But as mentioned when testing my Megger trips the upstream RCBO (DP 30mA) before completing the tests at the EV. Can we use a time delayed 61008 instead? Thanks

Commercial installs need to be using time-delay upstream so a dodgy EV doesn't trip out every single charger (which then get left offline for days causing lots of problems)

This is a very interesting subject. We've currently got a site where there's a dedicated 200Amp 6 way 3 phase board going in, with 5 MCB protected 3 phase Zappi chargers, all clipped direct. However the Zappi has an integral 30mA Type-A RCD with 6mA DC leakage detection in accordance with EN 62955. Now technically this complies and I haven't seen anything against it in either the manufacturers instructions or BS7671: Amd 2. I will call the NICEIC and MyEnergi and double check with someone more familiar with them than me.

I am surprised they are mandating the use of a type A RCD before the charger. As the tests demonstrate, with a type A RCD before before the charger, there is a problem with selectivity. The way to force selectivity and ensure the RCD in the charger trips before the upstream RCD is to use a delayed type RCD. Selectivity is not achieved by using RCDs of different values of trip current. That's a myth that higher trip current devices are slower. Some in reality might be, but you shouldn't be relying on it. So I think they are addressing the selectivity issue by ensuring that there are no other accessories or loads on the EV charging circuit, and hence mandating that the EV charger be on its own dedicated final circuit *and* that has its own dedicated RCD which doesn't feed anything else. In this way, it doesn't matter which RCD trips first: there is no adverse impact on any other circuit in the property if the upstream RCD trips first.

Be interesting to see if you had just a MCB upstream and then did the 5x test if the charge point protection would operate. Or would it be saturated and not function. 🤔 Also you can’t install a EV charge point on a split load board, or so Paul Chaffers from NAPIT told me. I asked him personally at ELEX regarding 722.531.3.101 which says they have to be protected individually by an RCD. Which seems ludicrous if I rock up to a property with a brand new CU, type A RCD and only 1 spare way. I can’t use a MCB I have to put in a new CU, be it an additional or replace the existing unless I can create a non-RCD way and use a RCBO. 🙄

Hi mark, to eliminate the issue of the x5 test and achieve selectivity, could you install a time delayed rcd/rcbo at source (providing it is not being used for additional protection) ?

Gooder

Those fooking EV charger manufacturer just don't equip their stupid charger with a 6mA DC leakage device.