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Cabling for HPWC Install?

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I’m looking to get the HPWC installed and want to check that the electrician is quoting the correct cable.

Before I get a quote, can someone confirm what would be required to support a 15m run for a 3-phase 32Amp installation? (as per manual : 400V AC three-phase: L1, L2, L3, neutral and earth ground).

From what I understand they’d use a cable that can support a higher amperage and a breaker that’s larger than required (ie 40Amp 3-pole)?

Would this cabling be what they’d use?
4 CORE 25mm XLPE COPPER MAINS CABLE [XLPE4C25] - $24.20 : ElectricianSupplies, ElectricianSupplies

Thanks,
Shane.
 
Have you contacted the Tesla approved installer in your area? They will already have all this information. 4-Core might not be the right cable, as a 3-phase HPWC will require 5 cores - 3 active phases, one neutral line and an earth line.

I have done and may do so again, but wanting to get alternate quotes as they seem astronomically high for the job as it stands.

Parts alone (15m of cable, breaker) at most should be around $500 cost. I'm finding it hard to understand why an initial quote I got from a "Tesla Approved" installer is almost $2000.

The job is easy - open roof space from meter box to wall of garage. Maybe 1-2 hours work (pulling cable mostly).

Thanks,
Shane.
 
No, 25mm is waaaay over the top.
Three phase actually needs thinner wiring than single phase. You’ll be running max 24A max on each line (24A x 240V x 3ph = 17.28kW).
I have a 40m run with 6mm and it’s more than enough. Don’t drop a volt. For a 15m run you could probably get away with 4mm, but I’d stick with 6mm.
So I would get 4c+e (4 core plus earth) at 6mm. That cable costs about $5/m.
TLE : Circular Unarmoured 4C+E 6.0mm PVC/PVC Org Sheath 450/750V
 
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I’m looking to get the HPWC installed and want to check that the electrician is quoting the correct cable.

Before I get a quote, can someone confirm what would be required to support a 15m run for a 3-phase 32Amp installation? (as per manual : 400V AC three-phase: L1, L2, L3, neutral and earth ground).

From what I understand they’d use a cable that can support a higher amperage and a breaker that’s larger than required (ie 40Amp 3-pole)?

Would this cabling be what they’d use?
4 CORE 25mm XLPE COPPER MAINS CABLE [XLPE4C25] - $24.20 : ElectricianSupplies, ElectricianSupplies

Thanks,
Shane.
Also, you need 4 core plus earth. The HPWC will not work without the earth wire. The earth is usually a slightly smaller gauge.
 
Out of interest - do you need 32A? If your car is newer than 2017, you can only draw a maximum of 24A with the new charger, so you could save yourself some cost by speccing it a little lower.

I say this, having installed a 32A-capable system myself, and rarely drawing more than 16A!
 
Out of interest - do you need 32A? If your car is newer than 2017, you can only draw a maximum of 24A with the new charger, so you could save yourself some cost by speccing it a little lower.

I say this, having installed a 32A-capable system myself, and rarely drawing more than 16A!
No, you don’t need it capable for 32A.
So long as it’s properly specced for a 24A load then it will be fine.
Having said that, Tesla might release a car capable of 32A again. I’d just spec for 32A, it won’t cost much more.
 
OK - I have a system installed but the electrician only installed a 3-pole 20 amp breaker, so the car will only pull 16 amps. Not sure what the cable he ran was - I've asked for documentation etc which he will provide but now I'm concerned it may be smaller than 6mm conductor size.

UPDATE: Damn it. Just checked. Elektra cabling. 2.5mm.

I guess I'll be getting him back, or dealing with a 16amp 3-phase connection.

Shane.
 
Last edited:
OK - I have a system installed but the electrician only installed a 3-pole 20 amp breaker, so the car will only pull 16 amps. Not sure what the cable he ran was - I've asked for documentation etc which he will provide but now I'm concerned it may be smaller than 6mm conductor size.

UPDATE: Damn it. Just checked. Elektra cabling. 2.5mm.

I guess I'll be getting him back, or dealing with a 16amp 3-phase connection.

Shane.
You should be able to increment up to 20 A on the charging screen.
Keep an eye on the voltage. If it starts to fall lower than about 228 the load is too much for your wiring.
Having said that, 16 x 3 x 240 is heaps. I wouldn’t bother pushing for more.
 
I am planning to get my HPWC installed soon aswell the manual for installation says the cable must be able to sustain loads of 40A , so which cable should i get i have a 3 phase meter and solar on single phase
 

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I recently had mine installed and it was MUCH cheaper for me to get it on a single-phase 32A circuit rather than 3 phase. This limits charging to around 7.5kW but I can still fully charge from completely empty overnight if I really need to so I didn't see that as a big limitation for me. Total cost of installation was $467 - it was reasonably close to a switchboard already in garage but had to go up over the top of a very tall garage as I wanted changing on opposite side to where switchboard was (about 15m of cable). Note I did not use the Tesla recommended electrician as I have my own very good one (who had done another Tesla charger before mine) who is the best sparky I have ever worked with - he is on Sunshine Coast but does do Brisbane work as well.
 
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I am planning to get my HPWC installed soon aswell the manual for installation says the cable must be able to sustain loads of 40A , so which cable should i get i have a 3 phase meter and solar on single phase
The 3 phase connection is 24A per phase. Just get a good electrician and show him or her the tesla wiring diagram. It is really quite simple, and you do not need a tesla authorised person. The diagnostic lights tell you if its right or wrong as well. Only thing that catches most electricians out is failing to set the dip switches per the manual, and restarting the circuit on completion.
If you have a single phase charger in your car then yes its a 40A circuit.
I had a single phase charger so installed a cable capable of single phase and 3 phase, which has worked out well with my new models s having the 3 phase charger.
 
The 3 phase connection is 24A per phase. Just get a good electrician and show him or her the tesla wiring diagram. It is really quite simple, and you do not need a tesla authorised person. The diagnostic lights tell you if its right or wrong as well. Only thing that catches most electricians out is failing to set the dip switches per the manual, and restarting the circuit on completion.
If you have a single phase charger in your car then yes its a 40A circuit.
I had a single phase charger so installed a cable capable of single phase and 3 phase, which has worked out well with my new models s having the 3 phase charger.
but how do i know if my car has a single phase or three phase charger
 
I recently had mine installed and it was MUCH cheaper for me to get it on a single-phase 32A circuit rather than 3 phase. This limits charging to around 7.5kW but I can still fully charge from completely empty overnight if I really need to so I didn't see that as a big limitation for me. Total cost of installation was $467 - it was reasonably close to a switchboard already in garage but had to go up over the top of a very tall garage as I wanted changing on opposite side to where switchboard was (about 15m of cable). Note I did not use the Tesla recommended electrician as I have my own very good one (who had done another Tesla charger before mine) who is the best sparky I have ever worked with - he is on Sunshine Coast but does do Brisbane work as well.
Thanks mate for the info, i am in Melbourne