Level 1 charger timer idea

I'm on SDG&E's time of use 2 plan (TOU2) and have solar. The 2015 Leaf 'S' that I'm leasing doesn't have the navigation system, which is apparently needed for the more sophisticated charge timers, and I'm using the level 1 charger that comes with it, combined with picking up some charge from Blink and NRG eVgo chargers near my work. Looking for a versatile, programmable charge timer for the level 1 charger, I came across the Belkin WeMo. You can find them on Amazon.com. It's basically a programmable wall outlet that you can turn on and off from your phone. You can set various timers on it, and enable/disable whichever timers you want, and the one I bought even tells you how much electricity went through it during it's last cycle. It's pretty neat, and it hasn't overheated on me yet or anything.

So, I have a timer called "super off peak - @23 miles" that turns on from midnight to 5am, and adds approximately 23 miles of range. I have another called "midnight to 10am - @40 miles" that spans super off peak and just off peak hours, but adds a little more range if I wasn't able to pick up enough charge during the day. I have another called "6pm to 10am" that's simply designed to make sure that the charger is turned off when it's probably not going to be in use anyway, etc etc.

My routine has been to look at the battery gauge when I get home, plug in, and pick a timer to activate, then deactivate the others. So far, it's working pretty well.

I hope that when I get around to installing a level 2 charger, I'll be able to find something this convenient.

I word of caution. I'm not an electrician, so I don't know how "safe" this is. We run multiple smoke detectors in and near the garage, for this and other reasons. Like I said, it hasn't heated up yet, and the amp rating of the device seems to be what's required, so I think it's safe, but you just never know.

You will be better served by focusing on getting L2 installed.

Agree you'll be much better off w L2, but at least check the specs on the WeMo against the EVSE draw, and check for heating. By the time the smoke detector goes off, you wake up, evacuate, and then MAYBE turn things off, damage has been done.

Rule of electrics and electronics: once you've let the magic smoke out, its very difficult to put it back in.

Well, I've charged for 16 hours on it without an issue. It's barely warm when I touch it in the morning, and it doesn't feel much warmer than when nothing is plugged into it.

I keep doing the math on the level 2 charger, and I just don't get how it adds up. I pay $0.16/kWh for super off peak midnight to 5am. I pay $0.22/kWh for off peak before noon and after 6pm. I get credited for my solar production at super on peak rates (well, they're super to me anyway)! On a long, round trip commute, I drive 60 miles in a day. On a shorter driving day, where I walk to lunch instead of driving, it's 50. So, estimating high, if I need 60 miles of charge per day, and I add 4.5 miles of charge per hour, I need roughly like 13 hours of charge on the level 1 (rounding down). 5 of those hours are at $0.16/kWh, and 8 of them are at $0.22/kWh, for an average of $0.20/kWh. So, a level 2 charger would save me $0.04/kWh in charging costs. Assuming I installed the thing myself (no, I'm not really that handy), and purchased it at $750 after tax, it would take 18,750kWh of level 2 charging before I was back to break even. At an estimated 3 miles per kWh, that means I would hit the break even point at 56,250 miles. If drive the EV for 15,000 miles per year, an investment in a self-installed, level 2 charger would hit it's break even point 3.75 years from now. Does anyone think they won't be cheaper and better by then? Regardless, my lease is up in 3 years, and all a level 2 charger in the garage does is reassure the car companies that I have a vested interest in signing a new lease. But what if the charger is incompatible with the car I really want in 3 years? I mean there's a thread on the Tesla board about how all they really need is a 240V outlet. A charger that works on a Leaf is apparently not compatible with a Tesla.

I'm sure I'm missing something here. I'm sure I've made a mistake in my calculations, because every EV owner I talk to says I need one of these, and I can't figure out why yet. Is it about range anxiety? Because there are chargers everywhere now. I look at plugshare.com, and the map is filled with them. They're practically at every street corner! In the 3 weeks since I leased the car, I've tried out 7 different locations, all empty, and all working. I've probably driven by that many others without stopping, just to make sure I know where they are. As long as I have a working Blink or eVgo card, I have no range anxiety. I do have EZ-Charge anxiety, but that's a different issue :roll:

It's really about how the car is used. I still use L-1 charging after 15 months, and it isn't usually a huge issue because when I drive it's usually one modest trip a day, or several short ones. L-1 is fine for that. I did buy an L-2 unit, and will get around to installing it, for the same reason most people prefer them: quicker recharge time when you need to drive more than once a day.

We used L1 and public L2s for a year. Driving went up, and the ability to reliably recharge in a few hours trumped the previous need for near perfect L1. Also public L2s were often taken. Can't believe we waited a year for our L2.

I think you shouldn't use the cost to buy a L2 EVSE for your figures. You should factor the difference between what you paid for it and what you could sell it for. I still see them going for quite a bit in the used market. In most cases, installing the 240 for it is pretty cheap if you can do it yourself.

Knowing the car is full every morning with lowest cost electric.... priceless.
16 cents is a rip either way.

ElectricMonkey said:

Well, I've charged for 16 hours on it without an issue. It's barely warm when I touch it in the morning, and it doesn't feel much warmer than when nothing is plugged into it.

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It appears that you have good wiring and if you want to continue to use L1 you should be fine.

I keep doing the math on the level 2 charger, and I just don't get how it adds up. I pay $0.16/kWh for super off peak midnight to 5am. I pay $0.22/kWh for off peak before noon and after 6pm. I get credited for my solar production at super on peak rates (well, they're super to me anyway)! On a long, round trip commute, I drive 60 miles in a day. On a shorter driving day, where I walk to lunch instead of driving, it's 50. So, estimating high, if I need 60 miles of charge per day, and I add 4.5 miles of charge per hour, I need roughly like 13 hours of charge on the level 1 (rounding down)...

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If you are using "4.5 miles of charge per hour" that suggests that you are getting about 4.2 miles/kWh. Is that about right? Your mileage efficiency will vary depending on how fast you drive and weather, to some degree, not that San Diego has much "weather". Given your mild climate, L1 charging will work better for you, with that fairly long commute, than it would for someone in the snowbelt.

... But what if the charger is incompatible with the car I really want in 3 years? I mean there's a thread on the Tesla board about how all they really need is a 240V outlet. A charger that works on a Leaf is apparently not compatible with a Tesla.

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Not true. A Tesla can use an adapter to fit any standard EV J1772 plug. And a simple 240 Volt wall outlet, if you want to go with that, will work fine for a LEAF if you spend about $330 to have your Nissan/Panasonic EVSE upgraded by EVSEupgrade, and that will give you 20 Amp 240 V charging (4.8 kW*, versus 1.4 kW L1). You don't have to spend $750 to get an L2 EVSE at home. One factor not in your numbers is that L1 charging is less efficient, about 75%, than L2 charging, about 86-91% depending on charging speed. So, L1 charging wastes more electricity than L2, not that it will make all that much difference in your calculations.

I'm sure I'm missing something here. I'm sure I've made a mistake in my calculations, because every EV owner I talk to says I need one of these, and I can't figure out why yet. Is it about range anxiety? Because there are chargers everywhere now. I look at plugshare.com, and the map is filled with them. They're practically at every street corner! In the 3 weeks since I leased the car, I've tried out 7 different locations, all empty, and all working. I've probably driven by that many others without stopping, just to make sure I know where they are. As long as I have a working Blink or eVgo card, I have no range anxiety. I do have EZ-Charge anxiety, but that's a different issue :roll:

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There are several things you are missing: not everyone lives in an area surrounded by the public charging infrastructure that you have. Not everyone lives in a mild climate that allows high mileage efficiency numbers all year and has no need for preheating (preheating in very cold weather works better on L2). Some people prefer to be able to charge quickly to increase the utility of the LEAF (trips in the evening after getting home from the commute, for example). Since you are willing to do that via public charge stations it might not be a factor for you.

If you are willing to get by with slow L1 charging, fine. Many others do the same. But most people prefer the convenience of L2, regardless of whether it is cost-effective in three years. If cost were the consideration, I'd still be driving the ICE car because it is much, much, much cheaper than driving a LEAF. So, it depends on what you want from driving your LEAF. For you L1 is fine: go for it. If your needs change you can think about home L2 charging then.


* 4.8 kW charging assumes that your S model has the charge package. Otherwise you will have 3.8 kW charging (16 Amps, 240 V).

4.2kWh/mile is about what the thingy on the dash reads, yes. Alot of times I get stuck in traffic (haven't got my HOV stickers yet), so I'm not using alot of energy.

I don't think I should upgrade the charger because it's part of the car and has to be given back at the end of the lease, right?

My other "car" is a GMC Yukon, which I own. It gets 15 miles to the gallon and has a high replacement cost. I did the math, and the lease payment on the Leaf is actually less than just putting gas in the Yukon for my commute, so the Yukon is just going to be for road trips and towing our gas-guzzling wakeboarding boat

ElectricMonkey said:

...I don't think I should upgrade the charger because it's part of the car and has to be given back at the end of the lease, right?...

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There are several options for lease returns:

• Just include the upgraded EVSE and 120 V adapter with the return. This has been done with no problems.

• Swap the upgraded EVSE for an unaltered one, plus some cash, with another LEAFer here at MNL (swap ads have become fairly frequent here now that leased LEAFs are being returned).

• EVSE Upgrade will downgrade the unit for you. [Although I'd be willing to guess that few if any people have taken them up on this option because the others above make more sense.]


So, a lot of leased LEAF drivers have had their EVSEs upgraded. There are other EVSEs available that can use a 240 V outlet, as opposed to being hardwired (and even hardwired ones can be removed and taken with you or sold).

It's up to you. I just threw it out as a possibility since you mentioned a 240 V outlet as a possibility for a future Tesla.

ElectricMonkey said:

Well, I've charged for 16 hours on it without an issue. It's barely warm when I touch it in the morning, and it doesn't feel much warmer than when nothing is plugged into it.

I keep doing the math on the level 2 charger, and I just don't get how it adds up. I pay $0.16/kWh for super off peak midnight to 5am. I pay $0.22/kWh for off peak before noon and after 6pm. I get credited for my solar production at super on peak rates (well, they're super to me anyway)! On a long, round trip commute, I drive 60 miles in a day. On a shorter driving day, where I walk to lunch instead of driving, it's 50. So, estimating high, if I need 60 miles of charge per day, and I add 4.5 miles of charge per hour, I need roughly like 13 hours of charge on the level 1 (rounding down). 5 of those hours are at $0.16/kWh, and 8 of them are at $0.22/kWh, for an average of $0.20/kWh. So, a level 2 charger would save me $0.04/kWh in charging costs. Assuming I installed the thing myself (no, I'm not really that handy), and purchased it at $750 after tax, it would take 18,750kWh of level 2 charging before I was back to break even.

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There is no need to spend $750 on a L2. Here is a good one at only $395.
http://www.clippercreek.com/store/product/charging-station-lcs-20-level-2/" onclick="window.open(this.href);return false;

I need roughly like 13 hours of charge on the level 1 (rounding down).

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A 120 outlet is really not designed to run at 12 amps for 13 hours straight. Many cases here on MNL where they overheat eventually.
How much is your safety worth ?

The OP is way overthinking this problem. Consider a L2 EVSE as an investment. If the car goes away, the used EVSE still has decent market value. It will likely loose less of it's original value % than the LEAF it supports. If unsure about keeping an EV, get a plug-in design with enough amperage to support the peak upload of your car. The nickel & dime approach will haunt your ownership experience.

Can any of you give me an idea of what it cost per foot of electrical wire to have 240 pulled? Our breaker box is at the exact opposite side of the house from where I need the charger.

Also, given that the 2015 Leaf S has a very basic charge timer that only allows you to specify an end time, how do you trick it into not starting the charge until super off peak? I don't want it to start the charge until midnight, and without the fancy little WeMo device, I'm left either trying to trick the car into behaving how I want it to, or finding a charger/EVSE that has built in timer functionality. I've tried tricking the car timer by giving it a later end time, and it still starts way too early. As for charge timers, from what I've read, the Blink home chargers have such functionality, but people have had quite a bit of trouble with them.

With midnight to 5 am being your super off peak I would just set the end timer to 5 am. Even with an on board 3.3 charger I doubt you would charge more than 5 hours so it will start sometime between midnight and 3 am and be done by 5. I have never had the charge time not be ready instead being done early. I actually set ours to be done at 8 am and my wife leaves about 7:20, she has yet to have it charging when she leaves.

Oh, also, if 240V is nothing more than 2 120V wires, as I've been told by various electricians, then why do people consider it unsafe to draw 12 amps from a single 120V wire that's on a 15 amp circuit, while safe to draw up to 60 amps on 240V wiring? I don't see how the math adds up. Are these like crazy amp rated wires?

And I don't get how a 120V wire can heat up over spec without blowing the accompanying circuit breaker. Isn't that what circuit breakers are designed to do?

ElectricMonkey said:

Oh, also, if 240V is nothing more than 2 120V wires, as I've been told by various electricians, then why do people consider it unsafe to draw 12 amps from a single 120V wire that's on a 15 amp circuit, while safe to draw up to 60 amps on 240V wiring? I don't see how the math adds up. Are these like crazy amp rated wires?

And I don't get how a 120V wire can heat up over spec without blowing the accompanying circuit breaker. Isn't that what circuit breakers are designed to do?

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If it's rated for it, it can take it. There's no reason why a 15 amp outlet can'T take 12 amps continuous. It is rated for it! Trouble is, just how many plug/unplug cycles is it rated for? Once you go over that number, its no longer safe. Whether it's a 15 amp 120 volt outlet, or a 50 amp 240 volt RV plug at a very well used RV park. I've seen some of those that got awfully hot when I was charging my car. Wires don't care what the voltage they are, only the current. Only the insulation cares about voltage, and most wire insulation is rated for at least 300 volts anyway.

There's no reason why a 15 amp outlet can take 12 amps continuous. It is rated for it!

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That would be "There's no reason why a 15 amp outlet can't take 12 amps continuous. It is rated for it! "

ElectricMonkey said:

Oh, also, if 240V is nothing more than 2 120V wires, as I've been told by various electricians, then why do people consider it unsafe to draw 12 amps from a single 120V wire that's on a 15 amp circuit, while safe to draw up to 60 amps on 240V wiring? I don't see how the math adds up. Are these like crazy amp rated wires?

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If I understand your question correctly, the "math" has to do with the current a particular gauge wire is capable of carrying with minimal potential (voltage) drop. And that has to do with the resistance of the wire. Smaller wire = higher resistance and greater voltage drop, which leads to greater heating (that energy has to go somewhere). Longer wires also lead to greater voltage drop, due to the cumulative resistance. For moderate length runs, a 14 gauge wire is safe for 120 Volts and 12 Amps. That gauge is NOT safe for a 20 Amp or higher circuit. There are many tables showing wire gauge, resistance, and safe current carrying capacity under various conditions (open, closed, length), e.g. this one:
http://wiki.xtronics.com/index.php/Wire-Gauge_Ampacity#Load_Carrying_Capacities_or_Ampacities" onclick="window.open(this.href);return false;

And I don't get how a 120V wire can heat up over spec without blowing the accompanying circuit breaker. Isn't that what circuit breakers are designed to do?

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Circuit breakers are to prevent too much current flowing. They don't protect against heat build-up from poor connections, too small wire gauge, and the like. A circuit breaker is intended to protect a properly wired circuit from an overload or short. That is a completely different thing from an improperly wired or worn circuit/outlet with high resistance. Hope that makes sense.

On the subject of 240 Volts versus 120 Volts, yes the 240 V circuit uses two "hot" wires, which are out of phase. The 120 Volt circuit uses one hot wire and a neutral. A 240 V circuit usually carries more energy because the devices that use it tend to use higher amperage and because of the 240 V potential difference.

A bit more arithmetic: Watts (power) = Amps x Volts. So, an EVSE that draws 12 Amps at 120 Volts draws 1440 Watts. An EVSE that draws 16 Amps at 240 Volts draws 3840 Watts. An EVSE that draws 30 Amps at 240 Volts draws 7200 Watts. (A LEAF with the charge package draws 6600 Watts, or about 27.5 Amps at 240 Volts; that's the maximum it can pull from a 30 Amp or higher rated Level 2 EVSE.)

And while I'm at it, Energy is power x time. So power is measured in Watts (or kilowatts, kW) and energy is measured in kilowatt•hours (kWh) or in joules. (1 joule = 1 watt•second, so 1 kWh = 3,600,000 joules.)

For those waiting to pick up a L2 charger, you can get the Schneider Electric EVlink for $500 from Home Depot by using the $100 off discount code.
See http://www.homedepot.com/p/Schneide...ic-Vehicle-Charging-Station-EV230WS/203670265.
This model includes a delay timer which can be useful in some situations. Use code EVLINKSUMMER to save $100 through 9/30/2014.

Veteran discount is 10% and there are lots of 10% off coupons that can be used to make this even cheaper.

Phil H.