HPWC install - isolation switch?

[EvaWilliams]

Then we should always get isolated switch for each and every gadget. Breaker panel can sometimes act as a villain. You should be careful while switching the panel on and off. Sometimes it can spray high-velocity shards of hot metal and plastic to the user's face. This can be very injurious, I have also read about it from an article (https://www.theshockdoctors.ca/blog/electrical-equipment/electrical-panel-main-breaker-safety/). So be careful while turning off the breaker panel.

 

[Flatbat]

Digging up a very old thread.

Planning to Install a HPWC right beside my meter box, in which its 32amp breaker/switch will reside. Surely I am not required to place a seperate isolation switch on the wall in this scenario?

 

[paulp]

Digging up a very old thread.

Planning to Install a HPWC right beside my meter box, in which its 32amp breaker/switch will reside. Surely I am not required to place a seperate isolation switch on the wall in this scenario?

Technically you are. A sensible electrician won’t.

 

[Shock-On-T]

Digging up a very old thread.

Planning to Install a HPWC right beside my meter box, in which its 32amp breaker/switch will reside. Surely I am not required to place a seperate isolation switch on the wall in this scenario?

I never have, and my last install was done by an electrician who also didn't (perhaps gently persuaded by me).
I always install chargers on their own circuit, so technically the breaker in the meter box is an isolation switch. Another advantage of having their own circuit is you can over-spec the wire gauge to really reduces your losses on such an energy intensive appliance (the car).
My car uses about the same power as the rest of my house combined (about 20kWh/day, around 40,000km/yr).

 

[Vostok]

The sparky who installed my HWPC last week did not put in a separate isolation switch. The HPWC is connected to its own 3-phase 32A circuit and RCBO, so either overcurrent or residual current would trip the breaker and the HPWC would be isolated. He said the type of RCBO installed is a new legal requirement this year, so presumably he would also know whether there is a legal requirement to install a separate isolation switch or not.

The RCBO is in a sub-board in a room above the garage so is not visible from the HPWC. The HPWC is hard-wired.

 

[Flatbat]

Thanks for the feedback. The reason I asked is this particular HPWC is to be mounted on a brick cavity wall, right beside the meter box (60cm away). This arrangement makes sense to use the flush mount bracket with wiring straight out the back into the cavity wall. If I have to install an isolation Switch this will necessitate using the top mount spacer to allow for external conduit. Any it is not a big deal. Will see what the sparky thinks.

 

[aegidius]

I think the idea is that anything hard-wired that might need servicing, needs a switch to isolate it and make it safe to work on. But that usually applies to ovens, aircons etc that are far from the meter box. You shouldn't need one if you're right next to the meter box but the law might say otherwise. (I remember in the old days with fuses, the sparky would take out the fuse and put it in his pocket, making it very hard for a third party to accidentally reconnect the circuit when he was off elsewhere working on it)

 

[Wol747]

I'll be having the HWPC connected for my Feb delivery - I was told that it comes WITH the Model S yet my understanding was that it is posted to the buyer a few days before pickup so as to have it installed and ready. Which is correct?

I don't know whether it's worthwhile having 3 phase put in (we are moving from a 3 p house to a 1 p house unfortunately!). Any ideas as to what breaker and circuit is worthwhile for the single phase? The HWPC will be fitted in the garage back-to-back with the CB panel on the outside wall.

 

[Shock-On-T]

I'll be having the HWPC connected for my Feb delivery - I was told that it comes WITH the Model S yet my understanding was that it is posted to the buyer a few days before pickup so as to have it installed and ready. Which is correct?

I don't know whether it's worthwhile having 3 phase put in (we are moving from a 3 p house to a 1 p house unfortunately!). Any ideas as to what breaker and circuit is worthwhile for the single phase? The HWPC will be fitted in the garage back-to-back with the CB panel on the outside wall.

You get it before the car arrives.
1 phase is plenty, You want highest amps possible, which is 32A on the current tech.
Whether 3 or 1 phase, it's still an overnight charge, and either will fully recharge the car from near-empty while you sleep.

 

[Flatbat]

You get it before the car arrives.
...

Nah, things have changed lately.

The HPWC will be in the boot of the car when you collect it. Certainly this is the case with m3s at the moment. Maybe the S is different? You might be able to arrange something ealier as a one off, once you have paid for the car, pre delivery. In my case I enquired about buying additional units beforehand and Tesla were happy to sell them to me, once I had a VIN. In the end I worked out it was far cheaper to buy extra HPWCs on gumtree. You can pick up brand new sealed units for two to three hundred less than the Telsa rrp.

Remember the car also comes with a Mobile Connector Will take a couple of days to charge your car at 10 to 15 amps but may tide you over.

 

[Shock-On-T]

Nah, things have changed lately.

The HPWC will be in the boot of the car when you collect it. Certainly this is the case with m3s at the moment. Maybe the S is different? You might be able to arrange something ealier as a one off, once you have paid for the car, pre delivery. In my case I enquired about buying additional units beforehand and Tesla were happy to sell them to me, once I had a VIN. In the end I worked out it was far cheaper to buy extra HPWCs on gumtree. You can pick up brand new sealed units for two to three hundred less than the Telsa rrp.

Remember the car also comes with a Mobile Connector Will take a couple of days to charge your car at 10 to 15 amps but may tide you over.

Yeah I don't know what they are currently doing, but I remember I had my HPWC for an agonising 6 weeks before I got my car.
The mobile connector is actually almost enough, unless you consistently do more than 150km/day. Model 3 gets more range for the same juice as the S or X,

 

[Wol747]

Yeah I don't know what they are currently doing, but I remember I had my HPWC for an agonising 6 weeks before I got my car.
The mobile connector is actually almost enough, unless you consistently do more than 150km/day. Model 3 gets more range for the same juice as the S or X,

Thanks both. I guess they were fed up with delivering the wall chargers and then having orders fall through!

 

[Chamii123]

I recently had my HPWC installed with it's own 3-phase circuit breaker.
Initially it was installed without an isolation switch but I had one installed the following day.
I use the isolation switch to turn off the HPWC when not in use to stop the faint but audible high pitch hum.

 

[paulp]

I recently had my HPWC installed with it's own 3-phase circuit breaker.
Initially it was installed without an isolation switch but I had one installed the following day.
I use the isolation switch to turn off the HPWC when not in use to stop the faint but audible high pitch hum.

My ears must be getting too old. Have two installed in the garage, can’t hear any high pitch hum.

 

[RowellG]

He is planning to mount an [isolation] switch next to the HPWC. I would really prefer not to have that...

Hi everyone who is following this particular post. I have specifically joined this group to provide the following response (though I have not read all previous responses)

I am an electrician and am currently installing one of these chargers. I wanted to provide a response as an electrician with an interpretation and reasoning. I am NOT providing technical guidance, and will NOT respond to questions, your installer must use their own skills to sign off on their own installation. I am trying to assist owners to understand their requirements.

The new rule book AS/NZS 3000:2018 is a little vague in some areas surrounding EVs. The previous rule book (AS/NZS 3000:2007 - didn't have a specific clauses, but they were also implied). In the current rule book, appendix P provides guidance on installation techniques, but is vague with isolation requirements. Other sections of the rule book are specific though, but they don't necessarily specify EV in context.

However, having spent an hour going over different clauses, I have contacted NECA, whose current tech advisor is an ex electrical energy inspector. We have reviewed all clauses that may relate to the installation of charging stations and both agree that an isolator must be installed for compliance - and safety.

Some things to reflect on are (these are compliance requirements):
* Socket outlets (of any size and type) must be fitted with an isolator. A charging station has a plug and socket.
* Energy converters (i.e. chargine stations converting AC to DC), must be fitted with an isolator. The charging station is an energy converter, converting AC to DC for charging purposes. If we consider solar, battery storatge requires an isolator for the battieries and the inverter.
* Appliances (yes this is an appliance) must be fitted with an isolator.
* Isolators must be installed in a location where there is direct line of sight and accessible at all times to isolate the appliance, socket outlet, or energy converter.
... there are no doubt other clauses as well.

If we consider this from a safety perspective.
* There are complex electronics that control the charging of EVs. Both the charger and EVs are expensive. Should a fault occur you would want to isolate the charger and EV within a short time frame.
* Should the device start to malfunction, you would want to isolate the device within a short time frame.
* Sometimes RCD/RCBOs (circuit breakers with residual current detection) don't work satisfactorily. Where a fault occurs, you need to islate the device quickly.
* Inverters fail, fires occur.... etc etc.

Summary
Whether you do or don't want an isolator, or have or have not got one currently fitted.
They are a mandatory item specified in AS/NZS 3000:2018 and previous rule books (though vague - they are implied), required for the safety of you equipment and EV.

I hope that helps owners with their choices.
Best wishes,
Greg.

 

[Shock-On-T]

My house has a lots of high-power appliances that don't have isolation switches (oven, stovetop, hot water service). They are all on their own circuits and use RCD breakers, as does my car charger.
Not sure what the point is of an isolation switch on a car charger. Can anyone think of a scenario where an isolation switch would provide any benefit?

 

[rohan_aus]

My house has a lots of high-power appliances that don't have isolation switches (oven, stovetop, hot water service). They are all on their own circuits and use RCD breakers, as does my car charger.
Not sure what the point is of an isolation switch on a car charger. Can anyone think of a scenario where an isolation switch would provide any benefit?

I believe this is now a requirement of the Australian standards that all high-voltage, direct wired appliances must have an isolator switch within 1.25m of the device for safety reasons:

Section 2.3.4.5, 4.8.2.3 & 4.19 of AS/NZS 3000:2018:
Every water heater, air-conditioning unit and heat pump system shall be provided with an independent isolating switch (lockable) installed adjacent to but not on the unut (at arms length or 1.25 metres).

I believe the above has since been amended to include EV Chargers. As such, if the EV charger is within 1.25m of your breaker box, the isolator switch is not required as the circuit breaker counts as an isolator.

Edit: Found more details (hard to get as you need to pay for AU standards documentation, see subsection D.

"7.9.3.4 Facilities for Mode 3 & 4 charging (Residential) An a.c. mains supply connection facility for Mode 3 electric vehicle charging systems shall comply with all of the following :-
(a) The final subcircuit cable shall have a minimum current carrying capacity of 32 A and shall not supply any other socket outlet or point in wiring;
(b) The final subcircuit shall be protected by a separate residual current device (RCD) of Type B or Type F complying with IEC 62432, with a maximum rated residual current of 30 mA which operates in all live (active and neutral) conductors. Combined RCD and overcurrent circuit-breakers (RCBOs) may be used.
(c) The a.c. mains supply connection facility shall be connected by direct connection in accordance with section 4.3.2.1.
(d) An isolating switch complying with clause 2.3.2.2.1, with a minimum current rating 32 A, shall be provided for the a.c. mains supply connection facility.
(e) The output socket or cable of the a.c. mains supply connection facility shall be installed at a minimum height of 800 mm from the floor."

 

[meloccom]

I had Air Conditioning installed about 2 years ago and there is an Isolation Switch next to the external compressor unit outside, so its not just car chargers.

 

[Shock-On-T]

I suppose my existing allowances are grandfathered in. Not sure why the electrician didn’t install an isolation switch for the HPWC.
I’m still struggling to think of any possible benefit of an isolation switch for an HPWC.

 

[RareEarth]

Perhaps if installed in a public area you could have a lockable switch.
Just had a HPWC installed (8m from switchboard), no switch.