Geekzone: technology news, blogs, forums
Guest
Welcome Guest.
You haven't logged in yet. If you don't have an account you can register now.




15165 posts

Uber Geek


# 257110 15-Sep-2019 23:06
Send private message quote this post

Hi guys. after my water tank question, I have another electrical question, and this time about the wiring for an electrical vehicle. It was specified on the plans for a new home, for a 32A circuit to be installed in the garage, to be used in the future for electrical vehicle charging, to future proof it. At the moment it just has a normal power socket on it, but eventually it will be hooked up to a EV charging station that plugs directly into an electric car. 

 

Now the electrician has named some of the circuits in the distribution board, we noticed that the EV socket is using a C16  circuit breaker as per the photo below, which appears to be rated at 16 A. S I understand 32 A allows a car to be charged in double the time. Would the fact that he has used a 16A circuit breaker indicate that it is likely that he hasn't wired it up with 32A capable cable? If so what would be the process of getting it correct...rewiring it?

 

The other concern is that there doesn't appear to be a dedicated RCD on this circuit. According to the note in the distribution board, the RCD 7 to the left is for all the power circuits on the right of the RCD. SO the circuit breakers to the left RCD7 don't appear to be on any RCD at all. However I was reading that an EV circuit must now be on a dedicated RCD in order to be compliant. Is this correct, does this EV need it's own dedicated RCD and must that have been installed? 

 

 

 


View this topic in a long page with up to 500 replies per page Create new topic
 1 | 2 | 3
599 posts

Ultimate Geek


  # 2318316 15-Sep-2019 23:43
One person supports this post
Send private message quote this post

The special RCD required is "Type B" they are expensive and massive.

https://oemaudio.co.nz/product/rcd-type-b-suitable-for-electric-vehicle-charging-nz-worksafe-approved/

 

With regards to the wire itself, somebody would need to know the size (cross sectional area), and approx run length, to determine if it can carry 32A.

Seeing the other issue I would probable assume the worst for this one.




15165 posts

Uber Geek


  # 2318320 16-Sep-2019 00:22
Send private message quote this post

Scott3:

 

The special RCD required is "Type B" they are expensive and massive.

https://oemaudio.co.nz/product/rcd-type-b-suitable-for-electric-vehicle-charging-nz-worksafe-approved/

 

With regards to the wire itself, somebody would need to know the size (cross sectional area), and approx run length, to determine if it can carry 32A.

Seeing the other issue I would probable assume the worst for this one.

 

 

 

 

Thanks for that. We will get an electrician to come and check the wiring onsite to make sure it is to the specified capacity, I hope it is but the circuit breaker doesn't look promising.  Yes the RCDs  do take up quite a bit of space on the  distribution board, looks like that one takes the space of 4 normal circuit breakers. If it is a requirement under the new AS/NZS3000, should they still be required to have installed it in order to be compliant? They were supposed to leave 20% space capacity on the distribution board for things to be added, which installing this will probably take it down to 10 percent. The whole point in specifying it on the plans, was to make sure the garage is future proof, and they were aware it was an EV. 


 
 
 
 


3496 posts

Uber Geek

Trusted

  # 2318321 16-Sep-2019 00:37
Send private message quote this post

Take the face place off the garage socket and check the wire behind. It should be thicker - it may even have the type and cross sectional size printed on it. I think you need at least 10mm cross section copper cable for 32A "officially" but it really depends on how much voltage-drop/loss/regulations/insurance-exclusions you want to work with. Here is a useful page:

 

https://www.jcalc.net/cable-sizing-calculator-as3008

 

I'm not sure if the table on there is correct though as it's saying 16mm is rated to 40A but we have it it on 63A breakers from the street. Just a note those cables can cost a tonne.

 

Note I am not an electrician or electrical engineer - I've been doing my own research on this stuff for my DC home project and also re-wiring AC throughput the property and working with the elctricial on that too. It may be worth getting a couple of different electricians for an opinion potentially?





Speedtest 2019-10-14




15165 posts

Uber Geek


  # 2318322 16-Sep-2019 00:44
Send private message quote this post

Zeon:

 

Take the face place off the garage socket and check the wire behind. It should be thicker - it may even have the type and cross sectional size printed on it. I think you need at least 10mm cross section copper cable for 32A "officially" but it really depends on how much voltage-drop/loss/regulations/insurance-exclusions you want to work with. Here is a useful page:

 

https://www.jcalc.net/cable-sizing-calculator-as3008

 

I'm not sure if the table on there is correct though as it's saying 16mm is rated to 40A but we have it it on 63A breakers from the street. Just a note those cables can cost a tonne.

 

Note I am not an electrician or electrical engineer - I've been doing my own research on this stuff for my DC home project and also re-wiring AC throughput the property and working with the elctricial on that too. It may be worth getting a couple of different electricians for an opinion potentially?

 

 

 

 

Thanks I might try that. I think the 32A ones are the same they use for ovens, so they are quite a bit thicker, but still relatively standard type of cable for a new home. So I think in terms of the cabling, it was just a case of them using one of those type of cables.


1716 posts

Uber Geek

Trusted
Lifetime subscriber

  # 2318323 16-Sep-2019 05:20
3 people support this post
Send private message quote this post

mattwnz:

 

Hi guys. after my water tank question, I have another electrical question, and this time about the wiring for an electrical vehicle. It was specified on the plans for a new home, for a 32A circuit to be installed in the garage, to be used in the future for electrical vehicle charging, to future proof it. At the moment it just has a normal power socket on it, but eventually it will be hooked up to a EV charging station that plugs directly into an electric car. 

 

Now the electrician has named some of the circuits in the distribution board, we noticed that the EV socket is using a C16  circuit breaker as per the photo below, which appears to be rated at 16 A. S I understand 32 A allows a car to be charged in double the time. Would the fact that he has used a 16A circuit breaker indicate that it is likely that he hasn't wired it up with 32A capable cable? If so what would be the process of getting it correct...rewiring it?

 

The other concern is that there doesn't appear to be a dedicated RCD on this circuit. According to the note in the distribution board, the RCD 7 to the left is for all the power circuits on the right of the RCD. SO the circuit breakers to the left RCD7 don't appear to be on any RCD at all. However I was reading that an EV circuit must now be on a dedicated RCD in order to be compliant. Is this correct, does this EV need it's own dedicated RCD and must that have been installed? 

 

 

 

 

 

 

 

Keep in mind that all the rules for EV chargers are "Guidelines" only, they are not a standard, they are not cited by the law.

 

even if the circuit breaker for the socket for this future EV charger is connected up it still must be protected by an RCD, if it's not then it's non compliant.

 

Do you have at least 2 RCD's on your distribution board?

 

Are there more than 3 circuits off each RCD?

 

Its beginning to look like your wiring has been done by a cowboy, maybe it's time to engage an electrical inspector to do a full compliance check?

 

 


226 posts

Master Geek


  # 2318821 16-Sep-2019 21:39
Send private message quote this post

I second @gregmcc's assessment. If there's a socket outlet on that circuit without an RCD it is not compliant.


2299 posts

Uber Geek

Trusted

  # 2318865 17-Sep-2019 06:33
Send private message quote this post

Putting aside the lack of an RCD, if the sparky did run 6mm2 cable, he might have put a lower rated MCB to match the better match the capacity of the socket - expecting you to upgrade the MCB when you upgrade the socket in future? My understanding is that MCB ratings are primarily about protecting the cable rather than sockets or things plugged in, but a 32A MCB on a single 10A socket would 'seem' weird at the very least.


 
 
 
 




15165 posts

Uber Geek


  # 2319390 17-Sep-2019 19:31
Send private message quote this post

Tracer:

 

I second @gregmcc's assessment. If there's a socket outlet on that circuit without an RCD it is not compliant.

 

 

 

 

At the moment there is just a normal powerpoint at the end of the circuit. We told the electrician just to install a normal power point at this stage as we  are not ready to install a charging station, plus we won't know what sort  of socket type of the charging station we want until we buy an EV which could be years down the track. But once we do, we would expect that the sparky would just come in and remove the power point, and then install the charging station over the top, and no further work to the distribution board would be needed. At the moment it looks like circuit breakers in the distribution board would need to be moved to fit the RCD in which is potentially quite of lot of additional work.


3496 posts

Uber Geek

Trusted

  # 2319464 17-Sep-2019 20:37
Send private message quote this post

mattwnz:

 

Tracer:

 

I second @gregmcc's assessment. If there's a socket outlet on that circuit without an RCD it is not compliant.

 

 

 

 

At the moment there is just a normal powerpoint at the end of the circuit. We told the electrician just to install a normal power point at this stage as we  are not ready to install a charging station, plus we won't know what sort  of socket type of the charging station we want until we buy an EV which could be years down the track. But once we do, we would expect that the sparky would just come in and remove the power point, and then install the charging station over the top, and no further work to the distribution board would be needed. At the moment it looks like circuit breakers in the distribution board would need to be moved to fit the RCD in which is potentially quite of lot of additional work.

 

 

I don't think they could put a higher capacity circuit breaker on if you have a normal power point though as it would exceed the rating of that power point. RCD is another story.





Speedtest 2019-10-14


3404 posts

Uber Geek

Trusted

  # 2319466 17-Sep-2019 20:38
Send private message quote this post

So if there is a normal 10 amp socket, he cant put a 32amp fuse on it because the socket could cause a fault and the fuse could not act as a protection device. 

 

When you replace the socket, you would then have to upgrade the fuse to match it and possibly as mentioned, the RCD at the same time. Its still quite possible that the correct cabling has been installed within the wall - it will be pretty easy to tell just by comparing the cable thickness behind two wall sockets. 

 

Another possibility is that the cable could be upgraded later if there is crawl space in the attic and the holes are wide enough to fit the new cable so it can be easily pulled through. 





Ray Taylor
Taylor Broadband (rural hawkes bay)
www.ruralkiwi.com

There is no place like localhost
For my general guide to extending your wireless network Click Here




Mad Scientist
20924 posts

Uber Geek

Trusted
Lifetime subscriber

  # 2319469 17-Sep-2019 20:46
Send private message quote this post

how many amps does the house mains need to be to accommodate this?

 

i was looking at a house and it had a 62amp single phase power main ... is that an issue?





Involuntary autocorrect in operation on mobile device. Apologies in advance.




15165 posts

Uber Geek


  # 2319497 17-Sep-2019 21:31
One person supports this post
Send private message quote this post

raytaylor:

 

So if there is a normal 10 amp socket, he cant put a 32amp fuse on it because the socket could cause a fault and the fuse could not act as a protection device. 

 

When you replace the socket, you would then have to upgrade the fuse to match it and possibly as mentioned, the RCD at the same time. Its still quite possible that the correct cabling has been installed within the wall - it will be pretty easy to tell just by comparing the cable thickness behind two wall sockets. 

 

Another possibility is that the cable could be upgraded later if there is crawl space in the attic and the holes are wide enough to fit the new cable so it can be easily pulled through. 

 

 

 

 

Thanks, yes that makes sense. I had forgotten that you don't want a regular socket ever being at risk of drawing that amount of power though it. I think it is likely therefore that the right cable has been used. We may instead therefore just get them to put in a blanking plate instead of a socket and not use it, so it can be setup easier for an EV in the future.


599 posts

Ultimate Geek


  # 2319510 17-Sep-2019 22:11
One person supports this post
Send private message quote this post

raytaylor:

 

So if there is a normal 10 amp socket, he cant put a 32amp fuse on it because the socket could cause a fault and the fuse could not act as a protection device. 

 

When you replace the socket, you would then have to upgrade the fuse to match it and possibly as mentioned, the RCD at the same time. Its still quite possible that the correct cabling has been installed within the wall - it will be pretty easy to tell just by comparing the cable thickness behind two wall sockets. 

 

Another possibility is that the cable could be upgraded later if there is crawl space in the attic and the holes are wide enough to fit the new cable so it can be easily pulled through. 

 

 

Fuses on circuit boards are quite rare these days.

My understanding is that the circuit breaker at the switchboard only serves to protect the wire from overload, not individual sockets. This is why it is common to have 10A sockets on circuits protected by 16A and 20A breakers. I haven't found anything to say a 32A breaker would be not allowed on a circuit with 10A socket outlets.



1716 posts

Uber Geek

Trusted
Lifetime subscriber

  # 2319540 18-Sep-2019 04:43
4 people support this post
Send private message quote this post

Batman:

 

how many amps does the house mains need to be to accommodate this?

 

i was looking at a house and it had a 62amp single phase power main ... is that an issue?

 

 

 

 

This is the typical household supply, And this is the problem with EV charging. a normal EV charger is 32 amps. it's like having another electric stove running overnight.

 

 

 

The power grid in NZ simply does not have enough capacity in the infrastructure for a mass move to EV charging, let alone the power generation capacity.....


Mad Scientist
20924 posts

Uber Geek

Trusted
Lifetime subscriber

  # 2319546 18-Sep-2019 06:22
Send private message quote this post

gregmcc:

 

Batman:

 

how many amps does the house mains need to be to accommodate this?

 

i was looking at a house and it had a 62amp single phase power main ... is that an issue?

 

 

 

 

This is the typical household supply, And this is the problem with EV charging. a normal EV charger is 32 amps. it's like having another electric stove running overnight.

 

 

 

The power grid in NZ simply does not have enough capacity in the infrastructure for a mass move to EV charging, let alone the power generation capacity.....

 

 

so it's ok to install the 32A charger in a 62A house main but not to be used during peak times?

 

forgot to mention the 62A single phase supply has a fuse ... where is the fuse and if you trip the fuse is it difficult to restore it?





Involuntary autocorrect in operation on mobile device. Apologies in advance.


 1 | 2 | 3
View this topic in a long page with up to 500 replies per page Create new topic



Twitter and LinkedIn »



Follow us to receive Twitter updates when new discussions are posted in our forums:



Follow us to receive Twitter updates when news items and blogs are posted in our frontpage:



Follow us to receive Twitter updates when tech item prices are listed in our price comparison site:





News »

Arlo unveils its first video doorbell
Posted 21-Oct-2019 08:27


New Zealand students shortlisted for James Dyson Award
Posted 21-Oct-2019 08:18


Norton LifeLock Launches Norton 360
Posted 21-Oct-2019 08:11


Microsoft New Zealand Partner Awards results
Posted 18-Oct-2019 10:18


Logitech introduces new Made for Google keyboard and mouse devices
Posted 16-Oct-2019 13:36


MATTR launches to accelerate decentralised identity
Posted 16-Oct-2019 10:28


Vodafone X-Squad powers up for customers
Posted 16-Oct-2019 08:15


D Link ANZ launches EXO Smart Mesh Wi Fi Routers with McAfee protection
Posted 15-Oct-2019 11:31


Major Japanese retailer partners with smart New Zealand technology IMAGR
Posted 14-Oct-2019 10:29


Ola pioneers one-time passcode feature to fight rideshare fraud
Posted 14-Oct-2019 10:24


Spark Sport new home of NZC matches from 2020
Posted 10-Oct-2019 09:59


Meet Nola, Noel Leeming's new digital employee
Posted 4-Oct-2019 08:07


Registrations for Sprout Accelerator open for 2020 season
Posted 4-Oct-2019 08:02


Teletrac Navman welcomes AI tech leader Jens Meggers as new President
Posted 4-Oct-2019 07:41


Vodafone makes voice of 4G (VoLTE) official
Posted 4-Oct-2019 07:36



Geekzone Live »

Try automatic live updates from Geekzone directly in your browser, without refreshing the page, with Geekzone Live now.


Support Geekzone »

Our community of supporters help make Geekzone possible. Click the button below to join them.

Support Geezone on PressPatron



Are you subscribed to our RSS feed? You can download the latest headlines and summaries from our stories directly to your computer or smartphone by using a feed reader.

Alternatively, you can receive a daily email with Geekzone updates.