3pete
Posts: 89
Joined: Tue Mar 19, 2019 9:03 pm

Re: Question on Installing Level 2 Charger @Home

Sat Jan 09, 2021 8:37 pm

eXodus wrote:
Sat Jan 09, 2021 3:49 am
The BMW charger has 12a x 115v = 1380w - meaning 1.4KW - the battery has 30kwh usable the charger is 90% efficient 30/0.9 = 33kwh for a full charge

33kwh / 1.4kw = 23.8h for a full charge
Yep. My point was 10h / 23.8h is closer to 40-50% than it is to 25% (it's 43% :geek:). So if someone's getting 25% charge off 10 hrs of charge with the provided OUC, the car must not be set to max charge rate or something else is hinkey.

But OP got an L2 EVSE that solves the charge speed so that makes L1 charging a moot point. :)

jadnashuanh
Posts: 5154
Joined: Thu May 22, 2014 2:07 pm
Location: Nashua, NH USA

Re: Question on Installing Level 2 Charger @Home

Sat Jan 09, 2021 9:22 pm

The vehicle can handle a maximum of 7400W, or 32A maximum current, whichever is larger. Electrical code in the USA calls for not loading the circuit for more than 80%, so a 40A circuit could handle a maximum of 32A EVSE, and a 50A circuit can handle 40A one. Yes, wire is probably a significant portion of the cost as will the labor for a long run.

IF you choose to use a unit with a plug, make sure than when you insert it, it is tight. If it doesn't take much pressure to insert it, the contacts are worn out, and things could overheat, melt, and possibly start a fire. There's usually no good reason to set the vehicle to less than maximum unless where you're plugging it in is shared with some other load and the combination might trip the breaker. Having a large EVSE won't overload the vehicle.

FWIW, on a CCS (dc high voltage charge), the i3 can handle up to 50Kw input, and the input voltage will be somewhere between 360-380 vdc or so, depending on where the batteries are in their charge cycle. When using acv (an EVSE), it can handle much less input power.
Jim DeBruycker
2014 i3 BEV, 2021 X5 45e
(The i3 will be sold soon, <17K-miles, interested?)

eXodus
Posts: 55
Joined: Tue Dec 22, 2020 6:06 am

Re: Question on Installing Level 2 Charger @Home

Sun Jan 10, 2021 4:49 am

labtebo wrote:
Sat Jan 09, 2021 9:12 am
https://drive.google.com/drive/folders/ ... sp=sharing
as what the others have shared:
For a nominal charging of 32 A - a 40A max circuit is more than enough.
40A circuit - 40A ckt breaker, 50A ampacity wire (90C #8awg for short runs, #6 for long runs), I recommend adding a lockable disconnect adjacent to charger ( i added a timer to ensure charging only during time of use periods)
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.
This is from the code book:

86-304 Disconnecting means
(1) A separate disconnecting means shall be provided for each installation of electric vehicle supply equipment
rated at 60 A or more, or more than 150 volts-to-ground.
(2) The disconnecting means required in Subrule (1) shall be
(a) on the supply side of the point of connection of the electric vehicle supply equipment;
(b) located within sight of and accessible to the electric vehicle supply equipment; and
(c) capable of being locked in the open position.


Since the chargers here mention neither have more then 60A or 150V to ground (240 is between the legs and 120V to ground) .
So a disconnect should not be required or? - it's ok to recommend one. Especially when the breaker box is far away.

Why do you think you need a disconnect? I mean the small chargers are not serviceable like an Air Conditioner which requires one.

alohart
Posts: 2208
Joined: Sat Nov 01, 2014 7:36 pm
Location: Honolulu, HI

Re: Question on Installing Level 2 Charger @Home

Sun Jan 10, 2021 11:36 am

eXodus wrote:
Sun Jan 10, 2021 4:49 am
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.
If the switch on your EVSE actually turns off power to it so that it is not idling and consuming a small amount of energy continously, a disconnect would not be necessary. True on-off switches are rare on EVSE's. Which EVSE do you have?

I had an on-off switch installed by a licensed electrician according to code adjacent to our EVSE so that our EVSE would not consume energy when not in use. It has an LCD that does not sleep or do anything to prevent burn-in, so I do not want it to always be on.
Aloha,
Art

2014 BMW i3 Arravani Grey, Giga World, Tech + Driving Assist, Parking Assist, DC Fast Charging, JuiceBox EVSE

eXodus
Posts: 55
Joined: Tue Dec 22, 2020 6:06 am

Re: Question on Installing Level 2 Charger @Home

Sun Jan 10, 2021 12:28 pm

My Blink HQ100
https://blinkcharging.com/products/hq-100/
has a switch on the right side and it sounds like relay is clicking on, after that it takes a few seconds for it to boot and get ready to do something.

It's a very basic charger, no monitoring, no display, only a delay button, 2 4 6 or 8 ours. But with all the incentives I got for less then $300 new.

I only got it for a month, so no idea how longterm quality is. It works and charges the car.

jadnashuanh
Posts: 5154
Joined: Thu May 22, 2014 2:07 pm
Location: Nashua, NH USA

Re: Question on Installing Level 2 Charger @Home

Sun Jan 10, 2021 5:32 pm

My Clipper Creek unit appears to draw about 3W at standby. I'm guessing that that runs the internal power supply that controls the logic board and powers the status LED(s). Not enough for me to worry about it - 20-30 cents a month, depending on your electric rates. FWIW, most electronics fail during turn-on, not during constant use. FWIW, I'm a big fan of having a surge suppressor mounted at the power panel to help everything. I put individual ones on higher dollar things like computers, stereos, etc. A little known brand to residential applications is Mersen...they make mostly stuff for industry, but have some suitable for residential use and without the big name brand, tend to be well priced.
Jim DeBruycker
2014 i3 BEV, 2021 X5 45e
(The i3 will be sold soon, <17K-miles, interested?)

eXodus
Posts: 55
Joined: Tue Dec 22, 2020 6:06 am

Re: Question on Installing Level 2 Charger @Home

Mon Jan 11, 2021 4:09 am

jadnashuanh wrote:
Sun Jan 10, 2021 5:32 pm
My Clipper Creek unit appears to draw about 3W at standby. I'm guessing that that runs the internal power supply that controls the logic board and powers the status LED(s). Not enough for me to worry about it - 20-30 cents a month, depending on your electric rates. FWIW, most electronics fail during turn-on, not during constant use. FWIW, I'm a big fan of having a surge suppressor mounted at the power panel to help everything. I put individual ones on higher dollar things like computers, stereos, etc. A little known brand to residential applications is Mersen...they make mostly stuff for industry, but have some suitable for residential use and without the big name brand, tend to be well priced.
This looks like a nice charger you got there. Yet 3w standby current is unacceptable these days. Did they put in a ancient transformer as power supply?
I got a laptop which is running at less then 2w idle. With screen on!

I'm in Florida, the lightning capital :P so a surge suppressor is part of my panel and every major appliances has an additional one and computers are behind UPS. I didn't know about Mersen, will look into their products. Thanks.

I got the charger in my garage last month for the expiring tax incentive and Amazon and Blink had been running a promotion. When I get my refund I think I got the L2 charger installed for about only $220 of my money.

eNate
Posts: 538
Joined: Mon Sep 09, 2019 5:33 pm

Re: Question on Installing Level 2 Charger @Home

Mon Jan 11, 2021 11:19 am

Just to add context to the EVSE power consumption :

From Clipper Creek:

A: ClipperCreek EV Charging Stations have very minimal standby energy consumption; the standby power draw on the HCS and LCS charging stations is approximately 2 watts.

For comparison, leaving an HCS-40 powered up for about 2 months (50 days) would have the same energy consumption as leaving a 100 watt light bulb on for 24 hours (a very small amount).


From Energy Star EVSE Scoping Report:

The measured standby power [of 13 EVSEs tested] ranged from 1.3 W to 13.4 W and roughly correlates with the amount of features offered by the EVSE including timers, flashlights, and network connectivity.

Clipper Creek units are fairly "bare bones" so two watts isn't the absolute lowest, but isn't awful.
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eXodus
Posts: 55
Joined: Tue Dec 22, 2020 6:06 am

Re: Question on Installing Level 2 Charger @Home

Mon Jan 11, 2021 12:33 pm

You are correct, it's not bad.
sorry I'm a energy efficiency nerd :P 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.

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