Question on Installing Level 2 Charger @Home

[eNate]

You are correct, it's not bad.
sorry I'm a energy efficiency nerd I got i3 BEV because I don't see the point of lugging around a engine which I use twice a year

3w x 8766 hours in a year = 26kwh that's more then 100 miles of driving.

Oh, no, I totally get your point, I wouldn't have guessed it that high, though in context it's at the low end of the norm.

My guess is improving this adds cost, but Clipper Creek domestically made units are already on the pricier side compared to units that have extra features such as wifi.

 

[alohart]

Clipper Creek units are fairly "bare bones" so two watts isn't the absolute lowest, but isn't awful.

I don't know why more EVSE manufacturers don't include on-off switches on their EVSE's. These could be low power switches because they'd turn off power to the circuit board and relay primary windings, not on the high-power side of the relay. The in-line switch I added had to be a more expensive high-power switch because it has to handle full charging power.

There's no reason that I can think of why an idle EVSE should remain powered at all times. It's not doing anything unless charging is active or a timer has been set for charging to start. It's a small waste of energy multiplied by more and more EVSE's which becomes a bigger waste of energy. The cost of adding an on-off switch would be minimal. Our EVSE takes only about 5 seconds to boot and be ready to charge, so turning it on isn't a problem.

Ours is a JuiceBox kit from 2014. If I hadn't specified an on-off switch when the electrician installed our charging circuit, I would add an on-off switch to our JuiceBox. I wish that I had thought about doing so when our charging circuit was installed. I could have saved a few bucks.

 

[obetbali3]

What do you mean with disconnect? My charger has a switch on the side to shut it off and buttons to change when it charges.
Why do you think you need a disconnect? I mean the small chargers are not serviceable like an Air Conditioner which requires one.

Yes. The Disconnect switch is really not required for evse less than 60A (codes are minimum requirement). I did complete my installation first without buying the evse yet, so for me to be able to complete the wiring, the disconnect switch at the end gave me the flexibility to complete the wiring while deciding what evse brand to buy.

Safety Switch: For EVSE rated at more than 60 amps or more than 150 volts to ground, a
means of disconnect must be installed in a readily accessible location and within sight of the
electric charging connector. If the disconnect is not in sight of the equipment, it must be capable of being locked in the open position (CEC §625.23). Depending on local code requirements, a fused switch may be needed if the switch is not readily accessible, or is not visible
from the main panel.

 

[jadnashuanh]

FWIW, I don't know how accurate the meter I have on my EVSE's supply is, so 3W may not be exactly correct. Given that most electronics fail when you turn them on, a device designed to stay on will probably last longer if you don't shut it off and on daily.

 

[eXodus]

FWIW, I don't know how accurate the meter I have on my EVSE's supply is, so 3W may not be exactly correct. Given that most electronics fail when you turn them on, a device designed to stay on will probably last longer if you don't shut it off and on daily.

A EVSE not like high end electronic. It's small circuit board and a simple relay. Nothing fancy. The charger truly sits in the car and the EVSE only tells the car how much current to draw.

The only thing I can see failing is the 240 -> 12v converter for the circuits board. The relay will fail after 5-10.000 cycles or if you unplug without letting the charger on the car stop before you pull the plug. That will burn the contacts.

 

[eXodus]

Oh, no, I totally get your point, I wouldn't have guessed it that high, though in context it's at the low end of the norm.

My guess is improving this adds cost, but Clipper Creek domestically made units are already on the pricier side compared to units that have extra features such as wifi.

When you work in Energy Economics - you just remember the 8766 as hours in year. Everything in that field is annualized.
Don't care about bi-weekly or monthly stuff. Standby is always.

I respect good quality products, I hate stuff which don't last. But I also know my use cases very well. I'm only charging at home once a week, The charger I picked gave me two years warranty - so I figure it should last 2x 365 = 730 uses without needing warranty. I only use it 52 times year, which means 730/52 = 14 years.
If I would use it more - I would have picked a higher quality item.

 

[alohart]

The relay will fail after 5-10.000 cycles or if you unplug without letting the charger on the car stop before you pull the plug. That will burn the contacts.

The J1772 charging standard that North American i3's implement prevents the charging plug from being unplugged while charging is occurring. A trigger must be pressed to release the plug lock. Pressing the trigger immediately stops the charging, so burned contacts shouldn't be a concern.

I'm not familiar with how or if the IEC 62196-2 Type 2 charging standard used in much of the rest of the world prevents the plug from being unplugged while charging is occurring. I have read about a shorter pin that disconnects before the power pins. When this shorter pin disconnects, charging is stopped before the power pins disconnect. I don't know whether this applies to IEC 62196-2 Type 2 charging. I would be surprised if power pins could be burned when unplugging under any circumstances.

 

[eXodus]

The J1772 charging standard that North American i3's implement prevents the charging plug from being unplugged while charging is occurring. A trigger must be pressed to release the plug lock. Pressing the trigger immediately stops the charging, so burned contacts shouldn't be a concern.

I go by ear - when I push the trigger it takes like 2 seconds until I hear a relay click. So if I would to yank the plug right away I could be able to get the plug out before that click occurs. When I looked at the j1772 standard - there is a 1khz PWM signal on the pin which gets changed when you hit the button.
https://www.fveaa.org/fb/J1772_386.pdf

While "immediately" should be a the standard - but computers and mechanical relays need a reaction time. Waiting 3 seconds until the click occurs, is cheap insurance

 

[user 7704]

I brought home a 2017 Rex a week ago and did a fair amount of research into charging. I settled for a very simple DIY solution that meets the needs EV owners whose requirement is to be able to fill back the battery overnight... meaning, drive during the day, get home, and have a full battery the next day.

Being DIY, I installed a 120/240 dual voltage 20AMP outlet with 12/3 wire in my garage and ordered a dual voltage charger from Amazon capable of 240V/16AMP charge rates. The wiring cost was $20 for the 20AMP breaker, $50 for the 12/3 wire, and $10 for the outlet, plate, and gangbox. The charger was $170 from Amazon.

The reason for 12/3 wire is the dual voltage outlet, which uses 1 hot (black) and neutral (white) for 120V and 2 hot lines (black and red) for 240V. I am able to run 120V/20Amp appliances w/o tripping a breaker in my garage since that is a shared circuit.

I thought about installing a bigger service using 6 or 8 gauge wire and decided against it for a host of reasons. I kept coming back to the objective of the solution being able meet the requirement to fill up overnight. Having large AMP draw capabilities was not a requirement.

Overall, I am happy with the solution. The charger plugs on the wall and the cable hangs on a couple of hooks on the ceiling making for a clean, out of the way, installation as the cable never touches the floor when on the hook or plugged to the car. I also used the 120V plug to run other appliances in the garage. Just keep in mind to not use high draw 120V appliances when the charger is drawing. That is not an issue since the car charges at night and the appliances used during the day.

Installing a big service box is nice but unecessary to meet the requirements.

 

[BL5]

16A / 240V (3.8 kW rate) might work for a small i3 battery, but if ever plan on buying a longer range EV it’s going to take a while to charge. Can’t imagine waiting 20+ hrs to charge up a Tesla with a 100kWh pack.

 

[user 7704]

Agreed on the part about a large Tesla battery but for the vast majority of use cases a 240V/16A charge is sufficient to fill up a daily driver battery overnight regardless of EV brand or battery size. The average driver in the USA does 250 miles a week or 50 miles a day. Double that to 100 miles a day and the 240V/16Amp still gets the job done overnight with room to spare.

When I was shopping for my i3 I found most cars are driven less than the 12K average. Mine was at just under 8K a year or 30 miles per day. Looking at used Tesla 3s tells similar stories. The reality is net range does not equate to daily average usage and thus the ability to replenish the available capacity overnight is not a pressing requirement for most EV owners (i.e., replenish 80+kw every day)

That is why I settled on the dual voltage 20Amp solution. I am able to meet my requirements to fill up overnight and the cost is 1/4 of the larger alternative. The bonus is I get a dual ovoltage outlet I can use for other needs. For the average EV owner choosing level 2 charger is one case where going home is better than going big.

 

[eXodus]

Agreed on the part about a large Tesla battery but for the vast majority of use cases a 240V/16A charge is sufficient to fill up a daily driver battery overnight regardless of EV brand or battery size. The average driver in the USA does 250 miles a week or 50 miles a day. Double that to 100 miles a day and the 240V/16Amp still gets the job done overnight with room to spare.

When I was shopping for my i3 I found most cars are driven less than the 12K average. Mine was at just under 8K a year or 30 miles per day. Looking at used Tesla 3s tells similar stories. The reality is net range does not equate to daily average usage and thus the ability to replenish the available capacity overnight is not a pressing requirement for most EV owners (i.e., replenish 80+kw every day)

Great on the numbers, that's what I'm also always preaching. You never charge from empty 99% of the time.
So it really doesn't matter how big the total battery is for home charger calculation. Only how far you drive.
Most EVs get are getting around 4 miles per kwh. To satisfy that with 50 miles a day - you need 14kwh/ day.

Most people sleep around 8 hours. My Level 2 - 30A does about 6kw - so for my car is full usually under 2 hours.

 

[jadnashuanh]

FWIW, I've seen my i3 (a 2014 BEV) pulling over 20A at the point where it's warming the batteries and the cabin at the same time. So, if you want to leave with a full battery and want to precondition and warm the batteries, you may not achieve that with something less for an EVSE. That 20A isn't constant, and tapers up and down, depending on the timing and the outside temperature.

 

[user 7704]

Great on the numbers, that's what I'm also always preaching. You never charge from empty 99% of the time.
So it really doesn't matter how big the total battery is for home charger calculation. Only how far you drive.
Most EVs get are getting around 4 miles per kwh. To satisfy that with 50 miles a day - you need 14kwh/ day.

Thanks!. I took an interest in EVs about a year ago and my observation reading many posts is that when it comes to choosing an L2 system for home charging most folks do not think in terms of "KWH capacity planning" for their daily charging needs and instead end up asking the question of how big a system to install and worried about the expense. The end result is folks often end up with an over-sized system ($$$) with lots of unused capacity.

In the rare event when the budget minded L2-16AMP system is unable to fill the battery overnight, the Rex will be there to fill any potential gap.

Deploying a big system at home is nice but folks should not feel compelled to install a large L2 system unless their daily capacity needs justify it, especially if cost is a concern to them.

So far my budget system has been used twice from about a 50% state, plugging in the evening and the system being fully charged to 100% before midnight. According to the vendor the system is limited to 16AMPS and should charge a 33KWH batter in less than 8 hrs. Time will tell, but I do not expect to see different results over time.

https://www.amazon.com/gp/product/B07CYQV2VL/ref=ppx_yo_dt_b_asin_title_o02_s00?ie=UTF8&psc=1

 

[jadnashuanh]

The cost of wiring (the materials and labor) can be a significant part of the cost to install an EVSE. Newer EVs will tend to have bigger batteries. So, IMHO, at least putting in the infrastructure for a larger unit, even if you buy a smaller one to plug or wire in, is prudent. What works well today, may be not the best choice in a few years. Pure EVs will tend to become the norm versus hybrids, so there's no quick backup should your battery not be sufficient.

Whatever works for you.

 

[user 7704]

The cost of wiring + breaker using 6 gauge is 3X the cost of a simple 12/3 240V/20A solution. If an electrician is hired the labor should be somewhat similar, the final cost depending on the hours spent running the wire.

For the DIY like me my expense was limited to $20 for the breaker, $12 for the dual voltage outlet, and $37 for the 12/3 50 foot spool of wire. About $70 total and 2 hrs of my time.

So far I charged 3 times with the Amazon budget 240V/16Amp device and the car was ready to go by midnight or about 7 hrs. The complete solution cost just under $250 and so far exceeds my requirement to have the car charged fully by morning with many hours to spare. For me, having a bigger charge rate would have required at least $500 more and in the end it would not have any impact on my utilization or ability to drive the i3's capacity every day. In the unlikely event my car is not fully juiced before departure the Rex can fill the gap.

If tomorrow I get a Tesla with lots of battery the situation would be the same... the miles driven per day, and thus the replenishment capacity requirements, will not change significantly to require faster charge rates.

 

[eXodus]

The cost of wiring + breaker using 6 gauge is 3X the cost of a simple 12/3 240V/20A solution. If an electrician is hired the labor should be somewhat similar, the final cost depending on the hours spent running the wire.

For the DIY like me my expense was limited to $20 for the breaker, $12 for the dual voltage outlet, and $37 for the 12/3 50 foot spool of wire. About $70 total and 2 hrs of my time.

So far I charged 3 times with the Amazon budget 240V/16Amp device and the car was ready to go by midnight or about 7 hrs. The complete solution cost just under $250 and so far exceeds my requirement to have the car charged fully by morning with many hours to spare. For me, having a bigger charge rate would have required at least $500 more and in the end it would not have any impact on my utilization or ability to drive the i3's capacity every day. In the unlikely event my car is not fully juiced before departure the Rex can fill the gap.

If tomorrow I get a Tesla with lots of battery the situation would be the same... the miles driven per day, and thus the replenishment capacity requirements, will not change significantly to require faster charge rates.

I agree with your notion that your charge profile does not change with battery size. Since this is more deepened on your driving then the vehicle. Almost all EVs get around 4miles/kwh. When you drive 40 miles every day - that will be 10kwh every day. No matter if you got a 20kwh battery or a 100kwh.


My cost breakdown for a 30A charger
- Breaker $10
- 25ft 8/3 wire $60
- Blink Charger (direct wire - no outlet required) $260
Total: $330

2 hrs time

 

[Anonymous]

I did the same DIY. Pretty simple job, especially if the breaker panel is located in the garage, like mine is - just had to run conduit from the panel at the front garage wall to the side wall near the garage door. Used oversize conduit to make pulling with wire easier. This video is a good guide.

https://www.youtube.com/watch?v=X9ro7Tc2nFI

 

[blackbelt]

Just bought my I3, and so far have only used the level one. I DO have a 240V 4KW wall heater in my garage. I plan on tapping into that feed and installing a 20A receptacle for a level 2 16A charger. As long as i don't try to heat the garage while the car is charging, it should work out just fine. I have a propane torpedo heater if i really need heat, but my garage is attached to the house so it always stays about 20-30 degrees warmer than the outside temperature anyway.

 

[eNate]

... I plan on tapping into that feed and installing a 20A receptacle for a level 2 16A charger. As long as i don't try to heat the garage while the car is charging, it should work out just fine. I

I have a similar shared arrangement, though with an air compressor. I installed a double pole double throw switch to select between the two. The air compressor is apt to fire up any time, even if I'm not using air, so the switch is just a good failsafe instead of relying on the breakers tripping.