[RustyBolts]

I know the Volt is limited to 3.3kwh charging, but can someone please explain to me why I can charge from empty in 3 hours 20 minutes on my 30A Siemens at home and 4 hours with a 15A Clipper Creek at work? I've timed it many times and there's a difference.

 

[llninja]

I know the Volt is limited to 3.3kwh charging, but can someone please explain to me why I can charge from empty in 3 hours 20 minutes on my 30A Siemens at home and 4 hours with a 15A Clipper Creek at work? I've timed it many times and there's a difference.

Your work voltage is 3 phase commercial, about 208V where home is 220-240V. I suspect if you were to swap EVSEs, you'll still see similar charging times (work will still be slower).

 

[hellsop]

I know the Volt is limited to 3.3kwh charging, but can someone please explain to me why I can charge from empty in 3 hours 20 minutes on my 30A Siemens at home and 4 hours with a 15A Clipper Creek at work? I've timed it many times and there's a difference.

208 v circuit at work, maybe? Compounded in complications by differences in the amount of power being used by battery temperature management outside vs in your garage?

 

[RustyBolts]

I'll read the fine print when I go in today, I'm sure it says on the Clipper Creek. Its actually a 16A, not 15A, Both home and work chargers are outside.

 

[Neromanceres]

As others have pointed out it's likely that your workplace is using a 208V three phase to the EVSE and your home will be 240V split phase voltage.

Power is Voltage times Current. Your car is likely pulling the same amperage at work and at home but the lower voltage is leading to less power being delivered into your car.

 

[RustyBolts]

As others have pointed out it's likely that your workplace is using a 208V three phase to the EVSE and your home will be 240V split phase voltage.

Power is Voltage times Current. Your car is likely pulling the same amperage at work and at home but the lower voltage is leading to less power being delivered into your car.

Do most level 2 EVSEs have the ability to compensate for the 208-240v range?

 

[ClarksonCote]

I'll read the fine print when I go in today, I'm sure it says on the Clipper Creek. Its actually a 16A, not 15A, Both home and work chargers are outside.

As others note, the difference is in the Voltage of the service. Your commercial location probably has 208V instead of 240V, or if not, still has a lower line voltage than what you have at home. That's the difference in time you're seeing.

Voltage * Amerage = Power.
At home and 15A, 240*13.75 = 3300 or 3.3kW charging rate.
At work and 15A, 208*13.75 = 2860 or 2.86kW charging rate.

2.86kW is 13% slower than 3.3kW.

4 hours is 20% slower than 3 hours 20 min. With charging "overhead per unit time" factored in that doesn't go towards charging the battery, this is about what you'd expect. So it seems that the charger at work uses 208V supply from the utility instead of 240V like inside your home.

Do most level 2 EVSEs have the ability to compensate for the 208-240v range?

It's not really an EVSE thing so much as the charger inside your car. But both have limits on current that need to be adhered to.

The Leaf, for example, can charge up to something like 16A or 20A, I can't recall which. Like the Volt, it is still limited to 3.3kW. But when there is a lower voltage, unlike the Volt, the Leaf can ramp up its current to a higher level if the EVSE can provide it, until it hits the max of either the EVSE or the car (whichever comes first), while it tries to maintain 3.3kW charging.

With the Volt, it's limited at 15A, so unlike the Leaf, it can't draw more current to maintain the 3.3kW charging rate. It's 3.3kW charging rate advertising simply assumes 240V is present.

 

[Norton]

I'll read the fine print when I go in today, I'm sure it says on the Clipper Creek. Its actually a 16A, not 15A, Both home and work chargers are outside.

Do most level 2 EVSEs have the ability to compensate for the 208-240v range?

Rusty,
Inside an EVSE there is a big-ass relay that sends power to the car's onboard charger.
It is either Closed or Open.
It has no control of power flow. It's ON or OFF.

It has a control board that has GFCI function and a 'Pilot Signal' system that sends a signal to the onboard charger to only draw 3.3kW or 6.6 or 7.2, 10, etc.
This is how a car capable of drawing 7.2kW can safely be plugged into a 3.3kW EVSE.

As said, It's probably the 3-phase-208 V vs. the 240 V-split phase grid power feeding the car.
Although I would hope the onboard charger limits wattage and not just amps, sounds like it doesn't.

 

[RustyBolts]

This all makes sense, thanks. However, I just talked to maintenance and they told me it was a 240v line.

 

[jeff_h]

This all makes sense, thanks. However, I just talked to maintenance and they told me it was a 240v line.

I noticed that there is a label on the box that says "Charging Station #3" so at work you are using one of several at that same location? When I am plugged in at work and monitoring status on the Chargepoint app, I can tell when someone else plugs in as it takes the flow from about 3.3kW to 3.1kW -- maybe your situation at work is similar?

 

[Neromanceres]

This all makes sense, thanks. However, I just talked to maintenance and they told me it was a 240v line.

That's actually fairly unusual. Typically 240V is in residential and some small commercial.

One other possibility is how long the wire is run from the main panel. Long cable runs will encounter voltage drop across the wire.

 

[RustyBolts]

I'm the only EV at the company.

 

[Norton]

This all makes sense, thanks. However, I just talked to maintenance and they told me it was a 240v line.

240V outlet is kind of a generic term.
It will usually not be exactly 240V if you walk up to an outlet with a multimeter and probe across the two hot lines.
Even on split phase, it depends on were you are located on the local grid.

Now ask the electrician if the building has 3 phase power coming into it.
Or ask one of them to probe an outlet in front of you to see what the exact voltage is in your building.

Be glad you have these L2 questions. Some Volt owners go through life on L1.

 

[flyingsherpa]

Your pic of the Clipper Creek even shows "Input: 208-240V"... most L2 EVSEs can handle the voltage range like that... the current is how they are rated, and they deliver the same current regardless of input voltage (unless the car is smart enough to ask for more when voltage is less, not all can do that), lower voltage means less power. And your Volt will report "240 V" on that status screen no matter what. I charge on 208V at work all the time and it's always said 240 too. For your situation, 208 makes the most sense, though I don't know why your maintenance guys said 240... were you talking to the right guys (electricians)?

 

[RustyBolts]

Your pic of the Clipper Creek even shows "Input: 208-240V"... most L2 EVSEs can handle the voltage range like that... the current is how they are rated, and they deliver the same current regardless of input voltage (unless the car is smart enough to ask for more when voltage is less, not all can do that), lower voltage means less power. And your Volt will report "240 V" on that status screen no matter what. I charge on 208V at work all the time and it's always said 240 too. For your situation, 208 makes the most sense, though I don't know why your maintenance guys said 240... were you talking to the right guys (electricians)?

My maintenance guy is by no means an electrician, there's a good chance he's wrong. I saw 240v on the breaker and assumed he was right. Looks like the clipper creek is 32A, not 15A like he said, so who knows.

 

[canehdian]

My maintenance guy is by no means an electrician, there's a good chance he's wrong. I saw 240v on the breaker and assumed he was right. Looks like the clipper creek is 32A, not 15A like he said, so who knows.

240V could just be the rating of the disconnect switch, not necessarily the voltage it is carrying.

Volt charger can do up to 15A maximum
@208V that's 3120W
@240V that's 3600W - BUT gen1 charger is limited by total power as well as current, so 3300W. Gen2 can take full advantage of [email protected], gen1 can't.

So you're looking at 5% less peak power to charge on a commercial/industrial 208 than a residential 240, and thus about 5% longer time.

 

[Neromanceres]

My maintenance guy is by no means an electrician, there's a good chance he's wrong. I saw 240v on the breaker and assumed he was right. Looks like the clipper creek is 32A, not 15A like he said, so who knows.

Two pole breakers are often rated at 208V and 240V. The reason is both legs of both voltages are 120V each. Except that 208V the two 120V's are 120 degrees out of phase so they add up to 208V. For 240V the 120V legs are 180 degrees out of phase so they add up to 240V. So either way the breaker is protecting two 120V legs.

 

[Aseras]

I can assure you that you are not charging with 208v.

208 1 phase is 208V to ground. 3 phase is 1 leg 208v, and 2 legs of 120v to ground. almost nothing evse included can use a 200v single leg without a transformer ( the clipper creek blink red and are very sad on 208 single phase, tried it )

120 is 120v to ground, 240v is 2 legs of 120v to ground.

that aside even 15a 240 is overkill, the most the volt will draw in a 240v plug is 7 amps per leg. a 15amp break would be 15 amps per leg, 30 amp is 30 amps per leg.

 

[Norton]

Sorry, I have to correct some of this:

I can assure you that you are not charging with 208v.>>He is if the building has 3 phase power feeding it. All the '240V' outlets are 2 of the 3 phases = 208V measured across the 2 hot leads and 120V each lead to ground.

208 1 phase is 208V to ground.>>There is no such power, at least in this country.
3 phase is 1 leg 208v, and 2 legs of 120v to ground.>>This is not correct. 3 legs of 120V.
almost nothing evse included can use a 200v single leg without a transformer ( the clipper creek blink red and are very sad on 208 single phase, tried it )>>???

120 is 120v to ground, 240v is 2 legs of 120v to ground.>>>Right. 240V is ONLY ACROSS the 2 hot leads and 120V to ground on each hot lead. The only place you have 240V is across the phases.
....

>Visualize a sine wave. That's 120V to ground. 1 hot lead. Typical 120V outlet.

>Visualize 2 120V sine waves on top of each other evenly spaced. That's where 240V comes from. The only place there is 240V is across those phase.

>Visualize 3 120V sine waves evenly spaced. That's 3 phase power. It is used in industry because it's a much more efficient way of powering motors and such. Thanks Nicola Tesla !!! We salute you!

>Visualize taking away only 1 of those 3 sine waves, leaving that 120° gap. That's where 208 V 2 phase power comes from.

So, IF the car's Onboard Charger limits Amps across the Hot leads and not the total power draw in Kw, then that is what this thread is about.
It sounds like that's the way the CAR operates on 208V 2 phase power.
It's not a problem. A lot of L2 EVSE's are wired in this way because of where they are located.

 

[davemac616]

So, I had a Clipper Creek CS-40 with Internet features (courtesy the electric company) installed last week and it's still early but I don't understand the behavior I'm seeing.

Friday night: 4.6kWh time 2:57 average rate 1.68
Saturday: 8.2 kWh time 2:12 average rate 3.73
Monday night: 6.53 kWh time 4:10 average rate 1.57

For Monday, I made a note of the car's estimated completion time; its initial estimate was about 1:45 of charge time on "station" but it took well over twice that long; shortly after after it was plugged in the estimate changed to 4:15. The car has always been set to 12A at home, not that it should matter here.

Obviously on Saturday it completed the charge pretty quickly, but the other two charges are puzzling. Clipper Creek suggested that the Volt might be tapering its intake as it nears completion, but wouldn't that have been taken into account in the estimated completion time? My experience with Volt charging at 120V (this car plus 2 MY 2012) has been that it finishes faster than estimated. Obviously I've never had L2 at home before; my L2 at work usually finishes slightly later than the estimate (which I think is because of the 208V commercial circuit and a lot of other chargers) but never as slowly as those two above.

(MY 2017)