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HPWC install - isolation switch?

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I have a Model X arriving in late Dec (in theory) and should shorlty receive my wall charger. I had a sparky around today to give me a quote for an install.

He is planning to mount an installation switch next to the HPWC. I would really prefer not to have that - this install will be in a car port next to our side entrance and so quite visible. I have found many pictures online of installations that do not appear to have separate switches (most of these are in the US I guess).

Does anyone know whether it is a requirement here to have an isolation switch in Aus? I am going to have a dedicated breaker after all - so could always shut power down that way if needed.

Appreciate any help on this. BTW I have three phase power in case that makes difference.
 
I have an isolation switch which can be locked. My electrician advised it - to prevent tampering - as the connector is located in the basement carpark of a block of units. My installation is single-phase.
Tesla connector and isolation switch.jpg
Tesla connector and isolation switch.jpg
 
Hi Jjdsyd, congratulations on the purchase, you will love it.

I have an HPWC at home (40a 1p) and one at work (32a 3p) installed by different electricians, neither have an isolation switch - both have compliance certificates.
I think they look better without the switch - there's a dedicated breaker on the board for isolation purposes.
 
I learned that the electrical code requires a disconnect nearby and visible from the HPWC.

The reason for it is to ensure that someone who is servicing the unit can cut the power to it and nobody else can turn it back on unexpectedly without them seeing it.

If your breaker box is visible and nearby from the HPWC, no disconnect is needed.
 
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I learned that the electrical code requires a disconnect nearby and visible from the HPWC.

The reason for it is to ensure that someone who is servicing the unit can cut the power to it and nobody else can turn it back on unexpectedly without them seeing it.

If your breaker box is visible and nearby from the HPWC, no disconnect is needed.

Not sure that I quite follow the logic for that reasoning? Only a licensed electrician should have the cover off to "service" the HPWC and what would they service anyway?

If an electrician was working on any other circuit in the house wouldn't they just isolate the relevant circuit breaker (which is very rarely in direct sight of where they are working) to install say a new power point, wire up a light fitting or wire in an oven etc.

I am not saying that I am right (I am not an electrician), it just doesn't seem to make sense? I would also add that when my HPWC was installed there was no local isolator installed.

This may be different when it is installed in a "public area" such as a shared garage or a commercial premises instead of domestic installation?
 
In the US it is a requirement IF the amperage of the circuit is over 60A. so, the ones that you have seen that did not have a disconnect were either done by the homeowner, or were installed with a lower amperage circuit. I don't know what the rules are for AUS (sorry), but it may be similar.

In terms of the reasoning... the idea is that when the amperage gets high enough, anyone working on the circuit wants to be absolutely sure that it cant be turned on when they have their hands in the box. Say, by a "helpful" helper. I've seen this exact thing happen (though on a lower amp circuit) when someone was working on a hot tub trying to figure out why it wasn't working, and the apprentice found that the circuit was turned off. He turned it on and went to tell his boss that he "fixed" the problem, and found the guy cursing and holding a melted screwdriver.

Had that been a 100A circuit, he might have been on the ground and really hurt instead of just annoyed and needing a new screwdriver.
 
In the US it is a requirement IF the amperage of the circuit is over 60A. so, the ones that you have seen that did not have a disconnect were either done by the homeowner, or were installed with a lower amperage circuit. I don't know what the rules are for AUS (sorry), but it may be similar.

In terms of the reasoning... the idea is that when the amperage gets high enough, anyone working on the circuit wants to be absolutely sure that it cant be turned on when they have their hands in the box. Say, by a "helpful" helper. I've seen this exact thing happen (though on a lower amp circuit) when someone was working on a hot tub trying to figure out why it wasn't working, and the apprentice found that the circuit was turned off. He turned it on and went to tell his boss that he "fixed" the problem, and found the guy cursing and holding a melted screwdriver.

Had that been a 100A circuit, he might have been on the ground and really hurt instead of just annoyed and needing a new screwdriver.

If it is a similar requirement here then that might explain the differnce in interpretation. All of the original HPWCs were single phase 40A max.

I understand that there are now 80A single phase units available. I wonder if the threshold (if it exists in Aus) is per phase or total? The three phase units have a maximum of 32A per phase.
 
My sister and brother in law used to own and run accomodation in the Hunter Valley. One day one of the hot water services needed repairs and the breaker for it was turned off and the occupiers of the affected building were notified that the hot water was being repaired. Around 45 minutes later one of the guests was caught at the switchboard turning the breaker back on....

The hot water service was not in sight of the switchboard. By pure luck no-one was hurt.

If there was an issue with the charger or the car then you need to be able to turn off the power quickly and safely - and finding a switchboard somewhere else may not be an option. I can understand the requirement.
 
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