Charger installation saying I need a load balancer
Discussion
NeoVR said:
Why are you installing a 22kw charger? very few modern EVs can utilize 22kw AC charging... (IIRC I think it may only be the Zoe!)
the majority of EVs that support 3-phase AC (and not all of them do) will only charge at a max of 11kw.
An EVSE capable of supplying 22kW over 3-phase would be able to supply 7kW over a single phase.the majority of EVs that support 3-phase AC (and not all of them do) will only charge at a max of 11kw.
An EVSE that was only capable of supplying a maximum of 11kW would most likely be able to only supply 3.5kW when reduced to one phase.
So, a 3 phase, 22kW EVSE has you covered for single phase charging, and 3 phase charging even if the vehicle is only capable of pulling 11kW.
Of course it really only makes sense if a) you have 3 phase already, b) are likely to swap around what you might need to charge rather than targetting a specific car you own.
stef1808 said:
I’m installing a 22kwh wallbox and now being told I need a load balancer
Researching more it seems it’s only really necessary for commercial buildings / retail parks with multiple chargers etc
Is it necessary as it’s also delaying the installation which is a problem.
I think we need more info. A 22 kW charger (not kwH!) would require 3-phase, do you have 3-phase to the house? What fuses do you have on each phase? Who is asking you to install the load balancer, the installer or the DNO?Researching more it seems it’s only really necessary for commercial buildings / retail parks with multiple chargers etc
Is it necessary as it’s also delaying the installation which is a problem.
CharlesElliott said:
I think we need more info. A 22 kW charger (not kwH!) would require 3-phase, do you have 3-phase to the house? What fuses do you have on each phase? Who is asking you to install the load balancer, the installer or the DNO?
I have 3 phase at home 60/400 on the fuse box. (Amps/volts i assume) planing to charger a Tesla Scwhich I believe can charge up to 16.6kWThe installer is asking for the balancer but since asking to confirm if I actually need it has gone quiet.
stef1808 said:
I have 3 phase at home 60/400 on the fuse box. (Amps/volts i assume) planing to charger a Tesla Scwhich I believe can charge up to 16.6kW
The installer is asking for the balancer but since asking to confirm if I actually need it has gone quiet.
It sounds like the installer is a bit confused (based on available info...)The installer is asking for the balancer but since asking to confirm if I actually need it has gone quiet.
I assume they think this is something to do with balancing phases... in which case for a 3 phase charger that isn't going to make any difference. The vehicle will pull what it wants (probably equally) from each phase.
If you had a carpark full of single phase chargers, I can see how it might be theoretically possible for say only the chargers on L1 to be being used and nothing on L2 and L3. It is extremely unlikely, but that would be the only need to try and actively load balance between the phases.
If they mean making sure the whole house load + EV load doesn't exceed the main fuse rating (which isn't load balancing), then unless you have huge loads at present, doesn't sound necessary. 16.6kW over the three phases is only about 24A per phase.
Even with a 60A main fuse, I wouldn't expect you to be pulling 36A per phase normally.
Of course, the installer has (probably) seen the job and may know more... maybe you have 40kW of storage heaters or something?
If it is a real problem, a better and probably cheaper plan would be to get the DNO to upgrade your supply. Possibly only needing the replacement of three fuses (depending on their infrastructure).
22kW AC charger is really silly thing to fit, because no EV is going to have an OBC (OnBoard Charger) that can take that level of power, because it's a huge cost for the manufacturer.
Pretty much all OBC's support 32A @ 240V, ie around 7kW on a single pahse, A few Zoe's had a 22kW OBC, but that got dropped simply because it is un-necessary. 10 hours overnight on a 7kW is 70kWh, which ought to be more than enough for most people most of the time (around 210 to 280 miles range per night)
Save you money and just fit a single phase EVSE @ 7kW
(OE's moved to DC fast charging because the "charger" is off board, ie they don't have to spend the money on it, just give it a connection to the HV traction battery with a couple of contactors and a socket)
Worth also noting that an AC EVSE is not a "charger" really, it's just a switch (Relay) that the car can control, the OBC is what does the rectification and power control
Pretty much all OBC's support 32A @ 240V, ie around 7kW on a single pahse, A few Zoe's had a 22kW OBC, but that got dropped simply because it is un-necessary. 10 hours overnight on a 7kW is 70kWh, which ought to be more than enough for most people most of the time (around 210 to 280 miles range per night)
Save you money and just fit a single phase EVSE @ 7kW
(OE's moved to DC fast charging because the "charger" is off board, ie they don't have to spend the money on it, just give it a connection to the HV traction battery with a couple of contactors and a socket)
Worth also noting that an AC EVSE is not a "charger" really, it's just a switch (Relay) that the car can control, the OBC is what does the rectification and power control
Max_Torque said:
22kW AC charger is really silly thing to fit, because no EV is going to have an OBC (OnBoard Charger) that can take that level of power, because it's a huge cost for the manufacturer.
Pretty much all OBC's support 32A @ 240V, ie around 7kW on a single pahse, A few Zoe's had a 22kW OBC, but that got dropped simply because it is un-necessary. 10 hours overnight on a 7kW is 70kWh, which ought to be more than enough for most people most of the time (around 210 to 280 miles range per night)
Save you money and just fit a single phase EVSE @ 7kW
(OE's moved to DC fast charging because the "charger" is off board, ie they don't have to spend the money on it, just give it a connection to the HV traction battery with a couple of contactors and a socket)
Worth also noting that an AC EVSE is not a "charger" really, it's just a switch (Relay) that the car can control, the OBC is what does the rectification and power control
Hi Max, not disagreeing at all, just adding a little.Pretty much all OBC's support 32A @ 240V, ie around 7kW on a single pahse, A few Zoe's had a 22kW OBC, but that got dropped simply because it is un-necessary. 10 hours overnight on a 7kW is 70kWh, which ought to be more than enough for most people most of the time (around 210 to 280 miles range per night)
Save you money and just fit a single phase EVSE @ 7kW
(OE's moved to DC fast charging because the "charger" is off board, ie they don't have to spend the money on it, just give it a connection to the HV traction battery with a couple of contactors and a socket)
Worth also noting that an AC EVSE is not a "charger" really, it's just a switch (Relay) that the car can control, the OBC is what does the rectification and power control
The OP stated they wanted a Tesla charger at 16kW. As far as I know, these are three phase, and if it is available, why not?
The main issue I see with 7kW chargers isn't that it won't charge overnight, but more that it might not fit in with your energy company's lower cost tariffs.
eg. Octopus offer 4 hours overnight at a lower rate.... It would be better to bang 4 hours of charge in at 1/3rd the price and twice the current, than 8 hours at full price. I know, that is ofset against the higher EVSE cost, there probably isn't much in it.
If I get 3 phase I would without a doubt fit a 22kw dual charger.
My current cars both max out at 11kw AC but any future car I had would be specced with the 22kw option
As others have said its very useful to shorten the overnight charge to align with preferential off-peak rates.
Its also just handy to be able to charge 2 x 11kw simultaneously or 1 x 22kw at a later date.
Oh and have a trio of powerwalls charging at the same time... all in the limited off peak window.
The difference in cost between 16A and 32A 3-phase chargers is insignificant so why not just enable all charging options and better futureproof the install.
My current cars both max out at 11kw AC but any future car I had would be specced with the 22kw option
As others have said its very useful to shorten the overnight charge to align with preferential off-peak rates.
Its also just handy to be able to charge 2 x 11kw simultaneously or 1 x 22kw at a later date.
Oh and have a trio of powerwalls charging at the same time... all in the limited off peak window.
The difference in cost between 16A and 32A 3-phase chargers is insignificant so why not just enable all charging options and better futureproof the install.
Also, just on this 22kW thing, what about those of us with a big solar array, 3 phase and a plan to buy a car at some point with 22kW capability? In my case, the ability to charge the car in say 3hrs bang in the middle of the day when the sun is making the panels hum makes a lot of sense. Bet I’m not the only one either.
Max_Torque said:
Pretty much all OBC's support 32A @ 240V, ie around 7kW on a single pahse, A few Zoe's had a 22kW OBC, but that got dropped simply because it is un-necessary. 10 hours overnight on a 7kW is 70kWh, which ought to be more than enough for most people most of the time (around 210 to 280 miles range per night)
Not disagreeing with much you've said, just corecting on the Zoes. I believe my Zoe50 CCS is still capable of 22kW AC, and the early ones without CCS (plus some of the Zoe40s) can do up to 43kW. But as you've said, very few cars can even do 11kW.Replied earlier, dunno where it went…
It’s a no brainer to go for 22kW if you have 3 phase.
A 11kW EVSE would be beyond stupid as cars with single phase would only charge at 3.7kW. You need that 32A per phase. Hardware, cable etc all right sized for the job at marginal cost.
EVSE will just have a CT clamp to watch household draw and then can lower charge rate if the total household gets high, I assume that will just go on a feed in on 3 phase same as a single phase supply?
Andersen A2 offers this for example or indeed the Wallbox Pulsar with power boost device.
Plenty of cars have 11kW.
It’s a no brainer to go for 22kW if you have 3 phase.
A 11kW EVSE would be beyond stupid as cars with single phase would only charge at 3.7kW. You need that 32A per phase. Hardware, cable etc all right sized for the job at marginal cost.
EVSE will just have a CT clamp to watch household draw and then can lower charge rate if the total household gets high, I assume that will just go on a feed in on 3 phase same as a single phase supply?
Andersen A2 offers this for example or indeed the Wallbox Pulsar with power boost device.
Plenty of cars have 11kW.
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