Best Charger for Condo?

[iluvmacs]

First, the limiting factor in this case is more the charger in the car than the EVSE you use (i.e. it isn't specifically relevant if you use a Tesla EVSE or a J1772). Yes, the EVSE must also be rated for the voltage, so both do factor in, but the point is that in no way can changing the EVSE help you here. Second, the car can take up to 277V power, typical industrial voltage, though unusual in the EV world (I don't believe any other vehicle or EVSE has been designed for 277V). No dice on 347V though, so yes you will need to step it down. It will be far cheaper and just as effective with a buck-boost transformer than with a standard isolation transformer, since you wouldn't have an isolation requirement. If you get the older HPWC that supports 277V, you could step down to that. If you are using a UMC or v3 HPWC, go to 240V. No reason to go all the way down to 208V.

 

[user212_nr]

(The "charger" is in the car and cannot take such voltages. The J1772 connector is basically a kind of extension cord. It sends to the car whatever voltage it received as input - 100-250V sometimes a little more.

In regards to the "step-down transformer", its not clear what you are doing. I remember your thread, (Best Charger for Condo? ). Are you talking now about a proactive install or an install just for one unit.

If it it the latter (a large install) then just leave it up to the engineers. If you are doing this for one parking space, it sounds very weird. The step-down transformers are not cheap, but if it is legal and it is affordable, then let them do it. Your building manager hopefully is competent, and can do the rest.

 

[afeudale]

@

Yeah, a step down transformer would work.
The max a gen 3 wall connector (and LR TM3) can handle is a 60A circuit, 48A charging, could set it up for a lower max though.
A single phase 15kW for one port is CAD $1,800 or so: 17104 - Q015PEKF - 15kVA 1 Phase 60Hz 600 V Pri x 120/240 V Sec Hammond Encapsulated Distribution Transformer, Copper
Three phase 600 to 208 Y would need to be 45kW for 3 wall connectors (could do more with their sharing feature): $6k: 17104 - P045PBKF - 45kVA 3 Phase 60Hz 600 D V Pri x 208Y/120 V Sec Hammond Power Solutions Distribution Transformer, Copper

Other brand, $2k CAD or so (aluminium windings and looks like it runs hotter): https://store.maddoxtransformer.com/products/3-phase-600v-delta-208-y-120?variant=2194339168265

J1772 would still need a transfomer to drop the AC or a full AC/DC converter/ controller to supply the proper voltage to the car.

Thanks mongo!

Good links. Our requirements aren't that high - even 3kW is enough charging for us So will probably look for smaller/cheaper transformers, but will make sure the wiring can accommodate larger if we ever decide to upgrade.

 

[afeudale]

First, the limiting factor in this case is more the charger in the car than the EVSE you use (i.e. it isn't specifically relevant if you use a Tesla EVSE or a J1772). Yes, the EVSE must also be rated for the voltage, so both do factor in, but the point is that in no way can changing the EVSE help you here. Second, the car can take up to 277V power, typical industrial voltage, though unusual in the EV world (I don't believe any other vehicle or EVSE has been designed for 277V). No dice on 347V though, so yes you will need to step it down. It will be far cheaper and just as effective with a buck-boost transformer than with a standard isolation transformer, since you wouldn't have an isolation requirement. If you get the older HPWC that supports 277V, you could step down to that. If you are using a UMC or v3 HPWC, go to 240V. No reason to go all the way down to 208V.

Thanks iluvmacs! Good call on the buck-boost as they are a lot cheaper than isolation txfrmers. Our car is a 2020 model, so I assume our UMC and doesn't support 277v, so 240v sounds reasonable

 

[afeudale]

(The "charger" is in the car and cannot take such voltages. The J1772 connector is basically a kind of extension cord. It sends to the car whatever voltage it received as input - 100-250V sometimes a little more.

In regards to the "step-down transformer", its not clear what you are doing. I remember your thread, (Best Charger for Condo? ). Are you talking now about a proactive install or an install just for one unit.

If it it the latter (a large install) then just leave it up to the engineers. If you are doing this for one parking space, it sounds very weird. The step-down transformers are not cheap, but if it is legal and it is affordable, then let them do it. Your building manager hopefully is competent, and can do the rest.

Thanks user212_nr!

Good memory about the original thread Yes, this has been an ongoing project for months now and I'm even a board member at the building! I can only imagine how painful it would be for a "regular" resident.

Yes, this would be an install for just our one unit. The electricians and building manager all seem to be incompetent (we're on our 3rd company already), so it seems like we need to tell them specifically what to do. Our maintenance manager is a former electrician and my background is as an electrical engineer, so hopefully we can figure out what to tell them...lol

 

[user212_nr]

Thanks user212_nr!

Good memory about the original thread Yes, this has been an ongoing project for months now and I'm even a board member at the building! I can only imagine how painful it would be for a "regular" resident.

Yes, this would be an install for just our one unit. The electricians and building manager all seem to be incompetent (we're on our 3rd company already), so it seems like we need to tell them specifically what to do. Our maintenance manager is a former electrician and my background is as an electrical engineer, so hopefully we can figure out what to tell them...lol

I see now that mongo has posted the price for a transformer at about $2,000. That doesn't include installation. It seems like an awful lot for one parking space. The transformer is also higher maintenance than a wire.

Best to find a source of 240v power near the space that you will electrify. Ideally, it should come right from your own condo, but realistically can come from anywhere. The cost of one 200' wire won't be all that much.

If you have to cut through some concrete and do some repaving, it will be expensive, but seems like a better idea than buying an expensive transformer.

 

[afeudale]

I see now that mongo has posted the price for a transformer at about $2,000. That doesn't include installation. It seems like an awful lot for one parking space. The transformer is also higher maintenance than a wire.

Best to find a source of 240v power near the space that you will electrify. Ideally, it should come right from your own condo, but realistically can come from anywhere. The cost of one 200' wire won't be all that much.

If you have to cut through some concrete and do some repaving, it will be expensive, but seems like a better idea than buying an expensive transformer.

Yeah, if transformers are that expensive, then running the wire from the electrical room is our next option. It's just that it's over a 200ft run....

 

[mongo]

I see now that mongo has posted the price for a transformer at about $2,000. That doesn't include installation. It seems like an awful lot for one parking space. The transformer is also higher maintenance than a wire.

Best to find a source of 240v power near the space that you will electrify. Ideally, it should come right from your own condo, but realistically can come from anywhere. The cost of one 200' wire won't be all that much.

If you have to cut through some concrete and do some repaving, it will be expensive, but seems like a better idea than buying an expensive transformer.

Yeah, if there were a 240 source, that would be handy. There is also potential cost shsting if the new distribution panel were fed by one larger unit (but that gets into loalld and cost sharing)

That transformer is also 5x the size they need. Switching to an autotransformer a 3kva three phase (connect windings in parallel) is $780 CAD or so Y003QTCB3L0U - Hammond Power Solutions - Transformer | Galco Industrial Electronics
And there are likely less expensive options out there.

EDIT:
Important note: The Gen 2 wall connector had limitations on the power sourcing. It required a center tapped secondary and each leg to ground to be 120V or less. So a 208Y/120 was ok, but a single 208 to neutral was not.
The Gen 3 manual does not addess these issues, so that transformer setup may not be valid.

 

[afeudale]

Yeah, if there were a 240 source, that would be handy. There is also potential cost shsting if the new distribution panel were fed by one larger unit (but that gets into loalld and cost sharing)

That transformer is also 5x the size they need. Switching to an autotransformer a 3kva three phase (connect windings in parallel) is $780 CAD or so Y003QTCB3L0U - Hammond Power Solutions - Transformer | Galco Industrial Electronics
And there are likely less expensive options out there.

EDIT:
Important note: The Gen 2 wall connector had limitations on the power sourcing. It required a center tapped secondary and each leg to ground to be 120V or less. So a 208Y/120 was ok, but a single 208 to neutral was not.
The Gen 3 manual does not addess these issues, so that transformer setup may not be valid.

Thanks! The main issue is that we're the only one in the building that wants charging, despite there being over a dozen EV's (trust me, I've asked them...). So no cost sharing, we need to go it alone.

Good call on the center-tapped and potential to ground requirements...hmmm...maybe running the wire from a 240v panel is still going to be the best bet.

Maybe we'll just move to a house and forget the whole thing! hahaha

 

[mongo]

Thanks! The main issue is that we're the only one in the building that wants charging, despite there being over a dozen EV's (trust me, I've asked them...). So no cost sharing, we need to go it alone.

Good call on the center-tapped and potential to ground requirements...hmmm...maybe running the wire from a 240v panel is still going to be the best bet.

Maybe we'll just move to a house and forget the whole thing! hahaha

If there is 240V available, that may be a good option. To save cost, they can run aluminum most of the way, then transition to copper before the WC. Lowest cost would be 2 phase wires and using the conduit for the ground path.

House would probably cost more

 

[user212_nr]

Yeah, if there were a 240 source, that would be handy. There is also potential cost shsting if the new distribution panel were fed by one larger unit (but that gets into loalld and cost sharing)

That transformer is also 5x the size they need. Switching to an autotransformer a 3kva three phase (connect windings in parallel) is $780 CAD or so Y003QTCB3L0U - Hammond Power Solutions - Transformer | Galco Industrial Electronics
And there are likely less expensive options out there..

$580 USD on the transformer is not bad, but is 3kVA enough? That is less even than a NEMA 6-20. A NEMA 14-50 is 12 kW.

A 15 kVa sounds like the proper size. From what I can find, kVA is greater than the number of kW that it provides, depending on power factor it only goes lower. In that case, the 240v line starts looking better.

Yeah, if transformers are that expensive, then running the wire from the electrical room is our next option. It's just that it's over a 200ft run....

Here is 500 ft of 4 guage wire for $510. You will also need some pipes

Southwire 500 ft. 4-4-4-6 Gray Stranded AL SER Cable-13100315 - The Home Depot

Realistically, $1,800 for the transformer might not be too bad.

Here is 500 ft of conduit for $300. Not sure exactly what your situation would need, but its a good lower estimate.

Southwire 1/2 in. x 500 ft. Alflex RWA Metallic Aluminum Flexible Conduit-55082102 - The Home Depot

 

[mongo]

$580 USD on the transformer is not bad, but is 3kVA enough? That is less even than a NEMA 6-20. A NEMA 14-50 is 12 kW.

A 15 kVa sounds like the proper size. From what I can find, kVA is greater than the number of kW that it provides, depending on power factor it only goes lower. In that case, the 240v line starts looking better.

OP said they could do 3kw (but yeah, a 20A 120V plug is almost 2kW), 15kW maxes out the charger. If this was group buy, a large 45kW (or more) 3 phase would be the way to go.

Charger should be near 1.0 power factor, so kva = kw in this case, not true for other loads.

 

[user212_nr]

Yes, this would be an install for just our one unit. The electricians and building manager all seem to be incompetent (we're on our 3rd company already), so it seems like we need to tell them specifically what to do. Our maintenance manager is a former electrician and my background is as an electrical engineer, so hopefully we can figure out what to tell them...lol

I thought/misread that you said "competent". Yeah, incompetent was the feeling that I got with the whole transformer on the lights idea.

Good memory about the original thread Yes, this has been an ongoing project for months now and I'm even a board member at the building! I can only imagine how painful it would be for a "regular" resident.

I think you spent a lot of time trying to figure out how to "future proof" your solution for all the residents rather than just how to run a wire and get power to your space. Now that you have narrowed it down, it is easier.

Our requirements aren't that high - even 3kW is enough charging for us

Have you considered whether or not you are able to live off a regular 15A 120V wall socket? That would provide 1.8 kW. Some of those outlets are on 20a circuits and can provide 2.4 kW. It doesn't make sense that you only need 20% more power than a regular socket can provide. Either you need a lot more, or you can make do with a regular outlet.

 

[Runt8]

Thanks! The main issue is that we're the only one in the building that wants charging, despite there being over a dozen EV's (trust me, I've asked them...). So no cost sharing, we need to go it alone.

What sort of crazy EV owners wouldn't want home charging? You Canadians, I swear...

 

[Rocky_H]

Just to make sure people realize who might be reading this: you can't run maximum current continuously. The car will only draw 80% of the circuit rating.

Have you considered whether or not you are able to live off a regular 15A 120V wall socket? That would provide 1.8 kW.

The car will only draw 12 out of that 15A. So 1.4 kW.

Some of those outlets are on 20a circuits and can provide 2.4 kW.

And it will draw 16 out of that 20A. So 1.92 kW.

 

[user212_nr]

Just to make sure people realize who might be reading this: you can't run maximum current continuously. The car will only draw 80% of the circuit rating.

The car will only draw 12 out of that 15A. So 1.4 kW.

And it will draw 16 out of that 20A. So 1.92 kW.

Yes, however we were talking about power supply. The OP stated that 3kw was "enough" for him, and we were discussing 3 kVA transformers, so the appropriate comparison was with the 1.8 kW from the 15A.

It is unclear where he got 3 kW from, but it sounds like the wrong number.

What sort of crazy EV owners wouldn't want home charging? You Canadians, I swear...

I'm thinking that this apartment complex has 120v sockets available, and that they are charging fine off that. Since the OP is in or near Toronto, they probably have a short commute and/or use the car only on weekends.

Add to that the cost of $2,000 - $5,000 improvements to property that they do not own, I think it can make sense.

 

[afeudale]

$580 USD on the transformer is not bad, but is 3kVA enough? That is less even than a NEMA 6-20. A NEMA 14-50 is 12 kW.

A 15 kVa sounds like the proper size. From what I can find, kVA is greater than the number of kW that it provides, depending on power factor it only goes lower. In that case, the 240v line starts looking better.



Here is 500 ft of 4 guage wire for $510. You will also need some pipes

Southwire 500 ft. 4-4-4-6 Gray Stranded AL SER Cable-13100315 - The Home Depot

Realistically, $1,800 for the transformer might not be too bad.

Here is 500 ft of conduit for $300. Not sure exactly what your situation would need, but its a good lower estimate.

Southwire 1/2 in. x 500 ft. Alflex RWA Metallic Aluminum Flexible Conduit-55082102 - The Home Depot

Thanks! Yeah, I think that the limiting factor is not the wire cost, but the difficulty in routing between floors, as our only electrical room is on P1 level and our parking spot on P2 level. That said, with the neutral requirement on the transformer, it will be our only option (running wire). Trying to find someone parked on P1 that wants to swap spots plus some $$ for them

 

[afeudale]

I thought/misread that you said "competent". Yeah, incompetent was the feeling that I got with the whole transformer on the lights idea.



I think you spent a lot of time trying to figure out how to "future proof" your solution for all the residents rather than just how to run a wire and get power to your space. Now that you have narrowed it down, it is easier.



Have you considered whether or not you are able to live off a regular 15A 120V wall socket? That would provide 1.8 kW. Some of those outlets are on 20a circuits and can provide 2.4 kW. It doesn't make sense that you only need 20% more power than a regular socket can provide. Either you need a lot more, or you can make do with a regular outlet.

Trust me, that was my first idea, as we can easily live on 2.4kW - but believe it or not, there are NO sockets anywhere nearby. Only outlets for heat trace wires on the piping and those can't be used You would think 120V sockets would be ubiquitous, but alas, they are not...

 

[afeudale]

Yes, however we were talking about power supply. The OP stated that 3kw was "enough" for him, and we were discussing 3 kVA transformers, so the appropriate comparison was with the 1.8 kW from the 15A.

It is unclear where he got 3 kW from, but it sounds like the wrong number.



I'm thinking that this apartment complex has 120v sockets available, and that they are charging fine off that. Since the OP is in or near Toronto, they probably have a short commute and/or use the car only on weekends.

Add to that the cost of $2,000 - $5,000 improvements to property that they do not own, I think it can make sense.

Believe or not, we've just been charging off public stations for the past 6 months. I work mobile, so I'll park somewhere near a starbucks and charge while having a 3-hour work/coffee inside Was working out well until pandemic/lockdown...lol. Now, I will go to a mall and park/charge there while sitting/working in my backseat - made a little wooden table to make life easier Lots of superchargers nearby, but want to treat the battery nicely and not SC all the time...

 

[jeremymc7]

Condo would pay for the transformers, panels, etc. and then residents pay for the wire run to their parking spot and for the charger itself (approx. $5k for the resident)
On top of that, there is a $15/mo. fee for the service + electrical usage of course.

Was toying with selling the huge house after two decades and moving back into a smaller condo. Charging has been a prime concern. There's been a handful of condos come up where they had chargers at their parking spots. In every case it was "only EV charger in the whole complex". If they paid anywhere near that upfront and on top of that fees and then power; well that just makes me want to never move back into a condo again.