120vac Charging

Please note, it's not recommended to draw more than 80% of continuous load on a 15 amp circuit. 12 amps x 120 volts = 1.44kw x 9 hours = 12.96 kWh. Assigned parking with access to a 120v outlet at a flat weekly fee saves them the trouble of metering and costly EVSE purchases.

Most household outlets are fused or breakered at 20 amps - I think the 15 amps represents an entirely safe 75% of that maximum

Don

Don, you don't want to go there. Mart's right. Quoting from a couple of random googlings:

NEC limits the load on receptacle circuits to 80% for portable appliances [210-23(a)]

NEC 210-21(b)(2) Total Cord-and-Plug-Connected Load
The maximum cord-and-plug-connected load on 15-ampere receptacles, supplied from either a 15- or 20-ampere branch circuit, is 12 amperes. - See more at: http://www.ecmag.com/section/codes-...le-210-branch-circuits-0#sthash.6f5DOP6b.dpuf

From personal experience I have some ugly pictures of cooked connectors caused by some of my other EVs drawing a full 15A at 120vac despite using good heavy-gauge (#10AWG) wires.

Back on topic, this is one of the concerns for charging at work using any old duplex outlet that might be in a parking garage: plugging in two EVs drawing 12A each may well overload the circuit. BTW, our stock Mitsu draws 8A, but it's my understanding that the upcoming 2014 model will have the option of selecting 8A or 12A.

I think it depends on what you read and where you read it

A quick search came up with this: "A 20A breaker should only carry 2400W continuously. However we should only size the load for the circuit to run 80% continuously or 1920W." 1920 watts is 16 amps

Keep in mind that most household outlets do not have a 'dedicated' breaker - Frequently 2 or 3 and sometimes even 4 standard outlets share the same breaker and feed wire, so it's easy to run the circuit up to the maximum the breaker can handle . . . . and most magnetic breakers will hold a bit more than their rated current before they trip. A single outlet on a dedicated breaker should safely handle 80% of the current it's breaker is rated for, or 16 amps in the case of a 20 amp breaker. The protective device (the breaker) won't trip until it sees a load significantly larger than that

Little if any problem for us recharging iMiEV's on L1, since few of us have an EVSE which could possibly overload a standard dedicated outlet . . . . but, it could be a problem if your outlet doesn't have a dedicated breaker - If your fridge or freezer kicked on while you're charging, you might trip the breaker

Don

How many workplaces will have a dedicated breaker on an outdoor outlet?

Mart said:

How many workplaces will have a dedicated breaker on an outdoor outlet?

Click to expand...

Surprisingly, a lot. I don't know about a dedicated breaker, but if you look around at any parking lot you'll find lots of outlets. Even outdoor lots with light poles, many light poles have outlets. For hotels and office buildings, this is all an EV owner really needs.

I would agree that it's likely most outdoor outlets on commercial buildings are probably dedicated outlets. The acceptable practice of stringing 2 or 3 outlets together is fine for a room in a house where it's unlikely more than one of the outlets will have significant loads (lights, TV's, radios, phone chargers, etc) but an outdoor outlet is frequently used for more heavy duty purposes - Saws, battery chargers, pressure washers etc

This is not to say all of them are dedicated outlets, but it's much more likely. If they had something else on the same breaker, it would probably overload the breaker if the outdoor outlet was used to power any serious load

Don

Here's a question, I have a clipper creek lcs25 (sun country highway in Canada ) it can work on 208/240v ,I have looked into using this at work but how do I know how the 208 is run, I have two block heater plugs side by side and have measured 208v using both plugs, in the instructions it says about how you get the 208v (delta or wye ), my question is how can I tell which way it's wired, is using two plugs (20a each) even feasible, I'm thinking something along the lines of a y cord with a nema twist lock , I get called into work for emergency repairs and am only there for 2-3 hrs, living 50 km away I use half my range at least (usually the worst weather) and would like a safety net for charging,

ndm, you've brought up a number of disparate points, some of which perhaps need clarification -

Canada, like the US, uses 120vac, usually a split-phase off 240vac.

Three-phase is often used in NA commercial establishments; public EVSEs are often driven off two legs of a delta-connected 3-phase system, producing 208vac. Our iMiEV charger works just fine off 208vac.

You mention using block-heater connections: I thought those are all simply 120vac outlets.

We had a discussion on using two 120vac outlets off our split-phase system to produce 240vac. See this post: http://myimiev.com/forum/viewtopic.php?p=8110#p8110

That post refers back to the Leaf forum which shows a safe circuit diagram to accomplish this: http://www.mynissanleaf.com/viewtopic.php?f=26&t=4774

There is also a commercial product called Quick220 for safely accomplishing the same thing.

In any case, using two separate outlets whereby each one is off a different leg of 240vac is certainly a viable way of getting you 240vac to speed up your charging time. Need to emphasize testing each outlet for proper polarity before ever plugging anything into it!

Could you perhaps ensure that you are indeed looking at three-phase and not split-phase and exactly what sort of power outlets you're looking at? Since they're only intended for block heaters, do they have a maximum current-draw associated with each outlet?

sorry clarity of thought is not my strongest suit! i will try this in point form and hopefully supply enough "known" information, i had brought up the possibility of donating my clipper creek to the facility in exchange for use of the evse, my boss was positive but noted that government facilities are slow to adopt or adapt new thoughts, he then suggested i "sniff around" for interim possibilities, i already pay a per diem to charge at work, which is great but during the winter season i can be callled in for either difficult long repairs or short simple fixes, which can be an hour, level 2 for 1 hr will get me home!

1-there are two block heater plugs side by side each is 120v, marked 20amp by facilities management ,i currently use one of these for level 1 charging
2-when i took my meter out to see if 240v was possible from the two plugs combined (best possible scenario) i found that going from one "hot" to the other plugs "hot" i saw 208v (id have to check again due to memory loss)
3-i then looked over the install instructions and saw the reference to delta and wye connections, id like to know if its possible to identify the connections with a multimeter and those two plugs
4-if this becomes an issue of "take my chances" i'll leave it be until they come around and take me up on the offer of a "level 2" photo op with the local newspaper!

ndm, from your voltage reading I suspect you indeed have access to two different 120vac outlets, each one off a different leg of a common 240vac input, and I think you can easily accomplish L2 charging! The voltage drop to 208v may simply be the voltage drop within the building, although 104vac for a 120vac outlet seems low. Probably want to check with your facilities people before committing. The 20A rating is nice!

Your LCS-25 comes with an unterminated input cable.

Here's what you can do:

If you don't want to build your own (as described on the myNissanLeaf forum link above), you can simply buy a Quick220. Probably want to get the 20 Ampere System with Locking Outlet (NEMA L6-20R Receptacle).

Now, get a NEMA L6-20P plug and install it on the input end your LCS-25 cable (carefully observing pin polarity).

Plug each one of the 120vac plugs on the Quick220 into the two outlets (AFTER FIRST CHECKING THE OUTLET FOR PROPER HOT PIN POLARITY AND GROUNDING with the tester supplied with the Quick220).

Plug the LCS-25 into the Quick220 and, voilà, you have an L2 EVSE!

It sounds like your workplace is using 3 phase, 208 volt current which is pretty common for commercial buildings

With 3 phase, any one of the three phases to neutral gives you 120 volts. Using any 2 legs of the 3 phase gives you 208 volts. I think your block heater outlets are a pair of dedicated 120 volt outlets, each fed with a different phase of the 3 phase, so . . . . you *should be able* to make a simple adapter which will allow you to use the to outlets to charge using 208 volts

Don