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Posted By Topic: Type B RCD P&A

gregwires
Mar 08 2018 08:41

Hello,

Has anyone sourced and fitted type B RCDs in NZ, making enquires in relation to EVSE supplies and getting “why do you want one of those” responses, and when a price and lead time was given it was twice the cost of the EVSE and 6 months away.




https://worksafe.govt.nz/laws-and-regulations/consultations/review-of-the-electric-vehicle-charging-safety-guidelines/
   

pluto
Mar 08 2018 09:38

What is the type, mode of the EV charger being used?

If you correctly understand the application of RCDs you would know why an Type B RCD is required for EV charging, PV inverters, UPS's and variable speed drives.

I would suggest you read a good RCD manufacturers document on the selection of the correct type of RCD to use.

Use Google use "RCD type selection"as the search word. European manufacturers ABB, Seimens and Dopeck all produce good information of the selection of the correct RCD type for a wide range of high power electronic packages.

There is a NZ produced RCD selection guide coming soon as part of EV charging review of the EV charging guidelines.

The 2 major factors that cover RCD selection are;
1. the DC residual current(both constant and pulsating) flowing in the AC input to the high power electronic device. If above 6 mA a type B or F RCD must be used. Above 10 mA another safety protection system must be used.

2. The waveform of an earth fault currents (both AS asn DC) in the input current to the high power electronic device.

The current AS/NZS 3000:2007 +A1 +A2 in clause 2.6.2.2 gives some limited guidance and the reference to IEC 62350 Appendix C gives more information.
   

pluto
Mar 08 2018 09:45

A new IEC document on RCD selection is IEC 60755 and was recently revised and published. It is very expensive to buy, so would recomend the use of a good RCD manufacturers information, until the NZ sourced paper on RCD selection is avilable.

Don't use an USA based manufacturers, unless certifed as complying with IEC Standards only, as they use GCFIs insted of RCDs which are electrically different and would not comply with ESR 2010 requirements.
   

gregwires
Mar 08 2018 09:45

Hi Pluto,

I'll rephrase, no problem with my understanding of why, question was from the wholesalers when enquiring.

What have you managed to have supplied in NZ and price in relation to a TYPE A RCD. the price I was given was 20 x that of a TYPE A
   

pluto
Mar 08 2018 09:54

The selling price is related to volume of units sold, I would conceed they will be dearer, because what is being protected is a complex safety issue for an RCD to cater for.

Even an inverter type air conditioning unit needs something better that a type A RCD to prevent nuisance tripping.

The AC input filter for EMC purposes if of an incorrect type will have high earth leakage currents and is the cause of some nuisance tripping when an RCD is used becuae the air conditiong unit is plug connected to a socket outlet in a domestic residence, bacause they were too lazy to use installation wiring and permenantly connect all parts of the sir conditioning unit.
   

WillJ
Mar 08 2018 10:03

We found Schneider to be the cheapest, but they are still horrifically priced, hopefully the price comes down as they get more use
   

ppaw1965
Mar 08 2018 10:15

Last time I priced a 4 pole type B from Schneider it was over $700. Was for a Danfos VFD. This was about 4 years back. I was asked why until I mentioned what it was for and got. Oh people have that problem with those.
   

mowgli
Mar 08 2018 12:46

I was scheduled to install a charging socket in a domestic house tomorrow. After seeing this thread checked the pending wiring rules and read the guidelines from Worksafe (linked above). Knowing what I now know I can't in good faith install a type A RCD.

Called my wholesaler - 63A 30mA type B, special order, trade $1900. Far out! So much for electric cars being cheap to run!
   

mowgli
Mar 08 2018 12:51

Trouble is, this customer is currently using an extension lead on a circuit protected by SERF.

A dedicated 20A circuit to an all weather socket outlet protected by a 30mA type A RCBO will be many times safer than what they have currently. What a conundrum.
   

gregwires
Mar 08 2018 13:30

I hear you, the price makes you ask for them to check it a second time. Looking at RS in the UK they are about £500, and single phase is very uncommon. Word on the street is EV owners are asking for a caravan socket to be installed in their garage.
That in its self is another can of worms as if you read the guidelines the Japanese or UK chargers in NZ that have had the input connector replaced with a Cee Form 16A are most likely not compliant either, and you see them T&T, again, I believe incorrect.

The cost of doing it right is frightful to a customer.

   

WillJ
Mar 08 2018 13:52

Check your wholesalers to check a few brands for pricing , they vary quite a bit
   

mowgli
Mar 08 2018 13:52

The cost of doing it wrong could be even worse.
   

gregwires
Mar 08 2018 14:17

This is right, hence the research.
   

pluto
Mar 08 2018 14:52

mowgli Mar 08 2018 12:51

Your comment (part only)

A dedicated 20A circuit to an all weather socket outlet protected by a 30mA type A RCBO will be many times safer than what they have currently.

My comment
What is being proposed for the EV charging guidelines currently being revised and the revised AS/NZS 3000:2018 is the following.

1. In a domestic garage in which a EV could be parked is to run a dedicated final sub circuit rated at 32 A (sized for correct voltage drop at 32 A) direct from the main switchboard to a socket adjacent for EACH EV vehicle. Noting that this final sub circuit(s) can not be used for any other point in wiring in the electrical installation.

2. At the remote end fit a soccket oulet with a adjacent control switch (and not of the auto switching type operated by inserting the plug) complying with AS/NZS 3112 15 A, IEC 60309, 16 A, or BS 1363 13 A. The socket outlet to be 800 mm (min) from the finished floor.

3. RCD protection by a double pole type B RCD to IEC 62432. Current protection for the final sub cicuit can be 20, 24 or 32 A can be combined in a RCBO if desired.

the above is for Mode 2 EV charging.

If Mode 3 EV charging is required , remove the socket outlet detailed above and replace by a 32 A isolating switch and direct connect the Mode 3 charger to the isolating switch and uprate the over current protection to 32 A.
   

pluto
Mar 08 2018 15:00

One final last thing for the maximum demand (MD) of the electrical installation.

The consumer mains must be able to deliver the MD of the electrical installation plus the full current of the socket outlet(s) being used for EV charging, there is NO diversity permitted for the EV charging socket outlets.

One EV charging system in an existing installation, I would expect most electrical installations will not require the consumer mains to be upgraded, but for 2 or more EV chargers the consumer mains is very likerly too small.
   

AlecK
Mar 08 2018 15:37

Yes having atype a RCD will be safer than just a SERF.
But it can't provide the level of safety required.
Pluto mentioned nuisance tripping, but that's the least of it. The big problem is that if someone is gettintg a shock from this circuits, because of straight DC in the "waveform" of the fault current, a Type A may very well not trip at all.

So yes, "safer"; but not safe enough.
Has to be a Type of RCD that can operate effectively given the likely waveform under fault conditions.

And yes, they're expensive. And probably can't even get a 2-pole on in NZ, so need to use a 4-pole - even more expensive. But still only equivalent to a few tank-fuls of fuel.

How much is a life worth?
   

mowgli
Mar 08 2018 15:45

Thanks Pluto. I found those clauses already in the link above. Good to know that those parts are likely to remain. Interesting that the guidance will suggest 32A cable capacity while the wiring rules will set a 20A minimum.

Interesting also that it specifies a garage as opposed to a carport or open parking.

My client has just bought a Toyota Prius hybrid petrol/electric. The charger is single phase rated 9A and fitted with a 3112 compliant all weather plug.

Since this is only supplemental charging I question whether it is a high power charging device and whether it would generate sufficient residual DC to upset a type A RCD. The proposed wording doesn't allow for a subjective assessment of the charger itself.

If the charger design was suitable for protection by type A either by manufacturer instruction or by lab test then I expect it could comply under part 1.
   

mowgli
Mar 08 2018 15:50

"Yes having atype a RCD will be safer than just a SERF.
But it can't provide the level of safety required."

100% agree. It's all or nothing in this situation.
   

pluto
Mar 08 2018 16:14

If the car was sourced from Europe the car markers handbook will tell what type of RCD is required because it is very dependant on the internal configuration of the high power electronics.

In Japan the use of RCD types A and B is very rare so the car handbook may be of little use for tythis information.

So use IEC 60755 2017 edition or RCD manufacturers type selection notes, but you will need to have an internal circuit of the battery charger to correctly select the correct RCD type for use in NZ.
   

AlecK
Mar 08 2018 16:19

For mode 2, we are installing a socket; but we have no control over what type of charging equipment might be used - so we can't take that into account. The next owner may have a different EV (or none) and consequently a different charger.



as for predicting the wave-form under (various) fault conditions, that's well beyond the training that most electrical workers get. Certainly beyond anything in my apprenticeship. So I'm happy to be guided by the experts, rather than gamble someone else's life that there will never be more than 6 mA of D.C. component..


   

gregmcc
Mar 08 2018 16:56

Currently doing a bunch of EV chargers, we gave the 2 pole versions a miss as they were too expensive, went with Schneider 4 pole units as we have a mixture of 1 phase and 3 phase EV chargers
   

mf51to1
Mar 08 2018 17:22

Do Schneider make 32A Type B 4 pole RCCB? Couldnt see one on their spec sheet and Tesla chargers are 32A 3 phase.
   

WillJ
Mar 08 2018 17:36

Yes Schiender do, we used them for the Tesla Chargers we did last year
   

mowgli
Mar 08 2018 17:57

Best I came up with was Schneider RCCB-ID 4P 40A type B 30mA. Trade just a little over the catalogue price. Availability 2-3 weeks.
   

SteveH
Mar 08 2018 23:13

"That in its self is another can of worms as if you read the guidelines the Japanese or UK chargers in NZ that have had the input connector replaced with a Cee Form 16A are most likely not compliant either, and you see them T&T, again, I believe incorrect."
That's what M under Unsafe Practices says- Use of EVSE that has a test tag to AS/NZS 3760 attached

Periodic verification of RCD might be another one- Testing of all RCDs using a purpose built RCD tester to verify the performance of the RCD IAW the requirements for the type of RCD under test
   

Andrew
Mar 09 2018 11:04

"My client has just bought a Toyota Prius hybrid petrol/electric. The charger is single phase rated 9A and fitted with a 3112 compliant all weather plug."

Are you sure this is mode 2 rather than mode 1?
   

mowgli
Mar 09 2018 13:51

Andrew, I haven't asserted mode one or two. I haven't physically seen the charger so am unsure whether it incorporates a pilot signal to the EV or not.

It matters not though when the new wiring rules require all sockets supplying EV in domestic to be protected by type B RCD.

As AlecK points out, once the socket is installed and marked as dedicated for EV then other than the plug type there is nothing to limit what type of charger can be connected.
   

Satobsat
Mar 10 2018 14:58

I have seen a few people charging EV's at motor camps through both 16A sockets on service pillars and outdoor 10A sockets on ablutions block. I wonder if motor camp owners have been made aware of the need for type B RCDs?
   

pluto
Mar 10 2018 20:00

Many motor camps don't have an RCD fitted to socket outlets used for supply to caravans, so the EV ends up with NO RCD protection at all.

However,as/nzs 3001 is under review and they may change.
   

Satobsat
Mar 10 2018 21:04

Many motor camps don't have RCD protection at all but it is not against regulation to be so. But charging an EV from a service pillar is. Was wondering if Camp owners have been notified that they must have type B RCD protection on their outlets when offering EV charging to customers?
   

pluto
Mar 11 2018 08:37

The EV charging guidelines are currently being reviewed and amended as required.

The AS/NZS 3001 caravan parks supply arrangements are currently being reviewed and amended as required.

The position on EV charging may be reviewed as this work is being carried out.

If changes are to be made for EV charging it will require an amendment to ESR 2010 which is currently not programmed to occur until later this year or next year.
   

gregwires
Mar 12 2018 09:17

In regard to comments by StevH, is T&T permitted on an EVSE, the reason I as is this section 12.2 in part 3 of the guideline

2.2 To avoid doubt: (a) an IC-CPD and an EV charging station are considered to be a fitting, not an appliance, so the provisions of Regulation 80(3) of the Electricity (Safety) Regulations 2010 do not apply.
(b) the testing referenced on AS/NZS 3760 cannot be applied to EVSE, including an IC-CPC and a charging cable.

   

Andrew
Mar 12 2018 12:34

I mentioned mode 1 vs mode 2 because you're not allowed to install a socket for mode 1 charging so it does matter. I don't know how it's supposed to be enforceable, but that's the rule.
Frankly, the whole situation seems a bit messy for mode 1 or mode 2 because the installer is not obliged to record the intended use of a socket.
   

mowgli
Mar 12 2018 20:39

Andrew, thanks. I read that aswell. I wonder how mode 1 charging works if not via some form of socket outlet.

It matters little in my case. The Prius charger is described by the OEM as being mode 2. So presumably the inline charger incorporates those protective measures described in annex P of the new rules.
   

Andrew
Mar 13 2018 09:45

The way I understand mode 1 is you can't install a socket especially for a mode 1 charger, but you can use an existing socket for it, or install a general purpose socket and then use it for mode 1 charging.
Similarly, you can install a 20A general purpose 3123 socket with only a type A RCD and then use it for mode 2 charging, but you can't install it specifically for mode 2 charging.
   

mowgli
Mar 13 2018 12:13

I suspect it might be simpler than that. All the diagrams depict a cordset without an inline charger. Larger EVSE may have a plugable cordset between the charger and the vehicle. For mode one charging the cordset must be attached directly to the EVSE.

I don't think the socket restriction is necessarily meant for the connection between the EVSE and the installation but rather between the EVSE and the vehicle. The proposed rules aren't very clear on this but when you think about the purpose of the pilot signal it makes sense.
   

mowgli
Mar 14 2018 07:16

I was right that it's simple. I was wrong about the plug/cordset. This is my reading of the Worksafe guidelines after listening to AlecK last night.

Mode 1 is plugging the EV directly into an AC socket outlet via a simple plug/cordset without any inline EV supply equipment. We're not allowed to install sockets for this because the fault scenarios are bad.

Mode 2 looks the same as mode 1 except there is EV charging equipment, that incorporates specific protection, between the socket and the EV. The supply to the EV is still AC. We're not allowed to install this in public.

Mode 3 looks like mode 2 except the charger equipment is permanently connected to the supply.

Mode 4 looks like mode 3 except the supply to the EV may be AC or DC.
   

pluto
Mar 15 2018 09:22

mowgli Mar 14 2018 07:16

2 points
1. the EV charging guidelinds are currently under review and there may be some changes made.

2. Some of assumptions you have are incorrect.


Mode 1 The charging device is contained inside the EV and a 230 V supply is provided to the EV by an supply lead. The RCD type is not specified.

Mode 2 The charging device is contained inside the EV (AC supply to the EV) and the connection cable contains a in cord protection device. The RCD type is currently specified as Type B RCD.

Mode 3 The charging source is externally mounted from the EV and the AC supply is connected by installation wiring and the connection to the EV is LOW current DC. Recharge times is Hours. The RCD type is currently specified as Type B RCD.

Mode 4 TThe charging source is externally mounted from the EV and the AC supply is connected by installation wiring and the connection to the EV is HIGH current DC. Recharge times is approx 20 to 40 minutes. The RCD type is currently specified as Type B RCD.

Recent IEC drafts on EV charging are now starting to adopt other types of RCDs (other than type B), or some other detection devices, provided that some operating conditions are prevented during normal operations.

The review of the EV guidelines may adopt these other devices. It will be at least a couple of months before the review is completed and issued for use in NZ.


   

gregwires
Mar 15 2018 09:50

Pluto, are you giving time frames from involvement? I'm seeing a project potentially go on hold pending the type A / B decision as the type B RCDs are a significant part of the investment (more than the Mode 3 EVSE identified). Any idea of timing would be great for finality.

Your description of Mode 3 is different, I understood it was essential a fixed mode 2 EVSE, still reliant on the on board electronics for the AC to Dc conversion.
   

pluto
Mar 15 2018 10:27

One fact of which I have be made aware of is the review comittee is meeting in Mid April to consider the submissions received for the EV charging guidelines review.

The outcome of the review will be very dependant of the submissions made and amendments being proposed by the IEC and UL and will all form part of the mix to be considered.

Remember EV's are all made off shore and most of the world's demand is only made in a few factories. In the case of EV charging systems, the position is fairly simular, all the worlds requiréments are made in a limited number of factories.

In tha stsndards area there are only 2 IEC and UL.

The NZ needs will therefore largely follow overseas practices with minimmal alterations (if any) for use in NZ.
   

SCADA
Mar 15 2018 12:52

The guidelines also state that a Type A RCD can be used if the manufacturer deems it suitable for EV charging.

My friend has a small Nissan Leaf. Requires A 16A supply. The smallest Type B RCD I can seem to find from Schneider is a 40A 4 pole version. This is going to require me to install an entirely new switchboard as the RCD has to be within the switchboard and there's no room for a 4 pole RCD. Which I think is stupid too. Why can't we install the RCD remotely close to the charging point?
   

mf51to1
Mar 15 2018 13:27

ABB have a 2 pole RCD type B, and that’s just having a quick search.
   

pluto
Mar 16 2018 08:50

SCADA Mar 15 2018 12:52
Your comments 1(part only)

The guidelines also state that a Type A RCD can be used if the manufacturer deems it suitable for EV charging.

My comment 1
When you look a what the RCD is expected to do under all conditions, and including earth fault conditions of the high power electronic failure, the use of type B is required. Also because of the arrangement or configuration of the high power electrionic switching devices theree is some DC currents flowing in the input power supply. The sensing coils in an RCD can be become saturated with this DC current and cause the RCD to operate in unstable manner, or worse still, not operate at all and not remove an electrical hazard it was installed to detect.

Your comment 2
Why can't we install the RCD remotely close to the charging point?

My comment 2
The use of RCD is based oa risk prevention and this includes all the wiring from the switchbaord to the device being supplied.

The fitting of an RCD in a switchboard also gives some mechnical, water, protection of the RCD device. It also gives some mechanical protection of the connecting cable (to the device being supplied (using an electrical basis) from damage by mechnical fixing devices (nails screws)
   

mowgli
Mar 16 2018 19:50

Thinking aloud... always dangerous!

If the troublesome DC currents exist between phase and neutral in the supply to the EV charger, then won't a DC potential exist across all branch circuits in the switchboard? If operation of a type A RCD on the EV supply would be compromised then what's to prevent the same happening to a type A RCD on an adjacent branch?

Or do these DC currents only exist under fault conditions in which case a type B RCD would isolate the fault before other branches became vulnerable.

Overall this seems like a interference failure. Ie failure of a device to manage interference that would affect another device.
   

pluto
Mar 17 2018 08:22

mowgli Mar 16 2018 19:50

Your comment 1 (part only)

Thinking aloud... always dangerous!

If the troublesome DC currents exist between phase and neutral in the supply to the EV charger, then won't a DC potential exist across all branch circuits in the switchboard?

My comment 1
The SUPPLY connection to each type of RCD is required to be connection to the main switch to give the Maximum isolation of the DC currents.

If RCDs of DIFFERENT types are connected in series, depending on the upstream type if will compresmise the operation of the downstream RCD.

In some configurations the RCDs will NOT operate at all under some fault conditions or at the very least won't operate at the correct time/current values required by ESR 2010.

your comment 2
If operation of a type A RCD on the EV supply would be compromised then what's to prevent the same happening to a type A RCD on an adjacent branch?

My comment 2
See above for the maximum segregation arrangements on the supply to EACH RCD type.

Your comment 3
Or do these DC currents only exist under fault conditions in which case a type B RCD would isolate the fault before other branches became vulnerable.

My comment 3
It depends on the configuration of the high power electronics (inverter), the DC currents (typically around 10 mA) is present when the
inverter is operating.

It is NOT related to fault conditions only.

Your comment 4
Overall this seems like a interference failure. Ie failure of a device to manage interference that would affect another device.

MY comment 4
There are a number of additional requirements for the use of RCD protection with HIgh power electronics.

Some training material is being prepared and will become available in the near future in NZ. Watch for Worksafe NZ monthly newsletters when it is released.

This material is also being included in Amendment No. 1 to AS/NZS 3000:2018 but the publication is some 18 months away.
   

mowgli
Mar 18 2018 08:27

Pluto said, "The SUPPLY connection to each type of RCD is required to be connection to the main switch to give the Maximum isolation of the DC currents."

This seems a little over the top. As if half a meter of 6mm switchboard flex will provide isolation of DC currents. Will this be a firm rule or guidance?
   

pluto
Mar 18 2018 08:37

mowgli
Mar 18 2018 08:27
Your comment
Pluto said, "The SUPPLY connection to each type of RCD is required to be connection to the main switch to give the Maximum isolation of the DC currents."

This seems a little over the top. As if half a meter of 6mm switchboard flex will provide isolation of DC currents. Will this be a firm rule or guidance?

My comment
It is the recommendation of IEC and RCD manufacturers because it will give the lowest impedance supply which assists in the suppression of the DC current in the RCDs.
   

mowgli
Mar 18 2018 09:02

Thanks Pluto. Following MIs is set to become mandatory. Will this rule out loop feeding and comb bus bars for supply to RCDs?
   

pluto
Mar 18 2018 10:07

mowgli Mar 18 2018 09:02

Your comment
Thanks Pluto. Following MIs is set to become mandatory. Will this rule out loop feeding and comb bus bars for supply to RCDs?

My comment
Most RCD MIs thast I have seen to date don't make this point in the installation of RCDs on the need foe a connection busbar,etc.

The new requirement came from the new switchbboard standard AS/NZS 61439 series and because it not a field work friendly type Standard to use, the requirement was also put in AS/NZS 3000:2018 for use by workers in the field. If you use pre-manufactured switchboards this requirement would or should be included in the manufacured switchboard.

What had to be covered was the requirement for switchboards manufactured in the field from protective devices, switches and the like and all mounted on a switchboard panel, AS/NZS 61439 does NOT directly cover the field manufacture of simple switchboards.
   

pluto
Mar 18 2018 10:16

To fully answer your original question.

The use of a busbar to give the incomimg mains supply to ALL RCDs would be satifactory when the incoming mains is directly fed from the main switch as this would give the lowest impedance source of supply on the input of ALL RCDs.

Ther import point to note RCDs should NOT be conected in series, in particular, if they are different types of RCDs.
   

AlecK
Mar 18 2018 10:55

And yet connecting RCDs in series is exactly what is going to be required by new edition of "3000" for junior education: 30 mA at switchboard and 10 mA in classroom - although in this case not different Types, just different ratings. Which will provide some, but not full, discrimination; depending on the actual leakage current in any particular incident.

It will also be the case where an EV charger unit includes an RCD, yet both the Worksafe EV guidelines and new edition of "3000" call for RCD at switchboard.

The issue of impedance upstream of RCDs also arises WRT DBs; where there will be a - sometimes considerable - length of submain between main switch and RCDs for final subcircuits.

So I strongly suspect this "rule" is more like "best practice advice", ie to place them at swbd rather than at individual points along the subcircuit.
   

pluto
Mar 18 2018 14:20

Another point to remember about submains. (n the cureent EV charging guidelines)

If the submain contains a PEN conductor to a switchboard (using the outbuilding provision) that submain can NOT be used for supplying an EV charger.
   

evanh
Mar 18 2018 18:08

Really?! That's a significant exception. Why?

   

evanh
Mar 18 2018 18:10

Oh, sorry, I'm not that familiar with terms yet. For some reason I thought that would be the most common setup.


   

evanh
Mar 18 2018 18:39

Hmm, I've just had a look at my own detached garage wiring. It has separate earth and neutral in the submain cable but they are screwed together into a single terminal in the garage board with earth and neutral bars linked.

There is an earth wire out to the metal cladding of the garage but there is no earth stake into earth mass.

I'm not terribly knowledgeable on what's allowed (EAS only) but it doesn't seem to fit figure 5.1 of NZS3000.

I would have expected the earth and neutral bars to be separate.

   

gregmcc
Mar 18 2018 19:52

Which was most likely the typical way it was done with sub mains when you shed was wired, although should a sub main be done now there would not be a MEN link in the sub board if there was an earth conductor run with the phase and neutral.
   

Sarmajor
Mar 19 2018 21:56

Your garage installation would have complied when it was installed and unless it has reached the point of being electrically unsafe it still complies.
   

AlecK
Mar 20 2018 08:40

More to the point, it is not a PEN submain so the "prohibition" mentioned by Pluto would not apply; even if it had any real force - which it won't unless / until new "3000" is cited by regulations.

So "can NOT be used" is far too strong a statement. Clearly PEN can be used, and right now is also fully compliant with ESRs, "3000", and Worksafe's EV charging guidelines (which currently make no mention of the issue at all).

The rule is in the new EV clause 7.9 of almost-published 3000; with a Note indicating that using PEN submains "prevents the correct earthing connections from
being provided for the electric vehicle charging system earthing failure detection
system". No explanation of HOW it "prevents"; and difficult to see how a PEN submain could be any worse than the PEN mains that every installation has.

And since Worksafe have said there's no safety reason to cite the new "3000" sooner than end 2019; clearly they aren't very worried about this particular issue.

   

pluto
Mar 20 2018 21:14

Interesting; work on the revision of the EV charging rules are about to start. If you read the draft Worksafe V2 EV charging rules the prohibited use of a PEN conductor for earthing connected to an EV charger is there. It come from IEC standard for EV charging stations so it is NOT an NZ only requirement.
   

Andrew
Mar 26 2018 14:14

From memory there was something that made the EV charging rules legally enforceable, but can anyone tell me what that is?
   

SCADA
Mar 28 2018 13:11

So I installed a Tesla Wall connector yesterday for the purpose of charging a new EV.
I used a 4 pole type B Schneider RCD #16752.
I tested the installation and everything was fine except the test button on the RCD doesn't trip the RCD.

I checked the Schneider Specs and discovered that the RCD operational voltage range is 230/400V but the test button operational voltage is 250/440V.

This particular install is only single phase so the voltage is too low to operate the trip circuit.

Using an RCD tester the results were great but I fear someone in the future may think the RCD is faulty.
Also I'm wondering if this effects compliance.

Would love to know if someone knows a good 2 pole version of a type B RCD as having to use a 4 pole RCCB and a MCB takes up a lot of space, plus it was very expensive.
   

AlecK
Mar 28 2018 13:17

I believe the problem is that the testbutton circuit is wired between phases so of course it doesn't work when used on a single phase
   

AlecK
Mar 28 2018 13:23

As always, it pays to look at product markings and read MIs
   

peter
Mar 28 2018 14:27

could you provide your own test Button . A "push to make" button and suitable resister . Mounted in switch board ?
   

pluto
Mar 29 2018 12:09

peter Mar 28 2018 14:27
Your comment
could you provide your own test Button . A "push to make" button and suitable resister . Mounted in switch board ?

My comment

I would NOT recoemend that approach, the test button circuit is required by the RCD standard to disconnect the test button circuit when the RCD has tripped. The test button circuit is usually a low wattage resistor as is not suitable for extended operating periods.

An external test button circuit would NOT provide the feature.


From else where in this post
When you read IEC standard (IEC 62423) for type B and F RCDs the detailed testing required for DC currents flowing in the AC loading is not easy to do in the field, and I would make an observation it is almost impossible to do in the field.

I have heard that if you speak to Schnieder there is a correct method (manufacturers instruction) to use a 4 pole (3 phase) device as a 2 pole device for a single phase supply.