Ingineer
Well-known member
Last Saturday I charged at the Vacaville (CA) DC Quick-Charge. From what I've been told, this unit was given to PG&E by TEPCO (Tokyo Electric Power Company), who are the people that originally developed the CHAdeMO standard. It's a big unit!
This station is publicly accessible right off I-80, however due to it's lack of UL listing (the Japanese don't typically use UL), some PG&E lawyer deemed it too much of a liability risk to allow the public to actually use it, and most of the time it's shut down. The unit conforms to CHAdeMO specification which is extremely safe and reliable, so it's lack of UL listing is a silly reason to shut it down. The Japanese have their own regulatory/testing system called JET, and I'm sure this unit is JET listed. Do you think TEPCO, also being a public power company, would put it's name on something unsafe? UL listing is not a requirement for equipment in almost all parts of the US, and it's an independent testing lab, that is not affiliated with any government agency.
PG&E submitted a proposal to the City of Vacaville to purchase a new UL listed charger, and if accepted, this unit would be replaced. But Vacaville must pay for it, as PG&E supposedly is forbidden to do this by some regulatory tenet.
The location also contains a decent assortment of other charger types, mainly J1772 Level 2, but some SPI's as well. The parking spaces are covered by a large solar array which provides a nice shade. I suspect this location generates way more power than is every used by EV's!
Ok, on to the fun part!
The handle is physically easy to deal with, it's light and rugged, but admittedly not intuitive. There is a red lever and a big black handle that is very "gas-pumpish", and you have to release/lock the thing with the red lever and then engage the internal connectors using the big black handle. The effort is very low, once you get the order correct. Once charging, a solenoid locks the connector in the car, and will not allow release until you stop the charging. Seems to me, they could have replaced the solenoid with a small motor and then it would have been much simpler to use, and even less force required.
So, within a minute of connecting the handle and pressing start, the amperage shot up to 125a and pretty much stayed there for quite some time. (+/- 1 amp)
The display shows real-time Volts, Amps, and SOC (State-of-Charge) as a percentage bar-graph. It also attempted (poorly) to estimate how long the charge would take. Note the date and time are also way off. I'm surprised it's set at all with the power being off most of the time. (It must have a battery)
The way CHAdeMO works, the QC (Quick Charger) receives commands from the LEAF via a CAN (Controller Area Network) connection every 100ms. These messages tell the QC how many volts/amps to deliver, and the charger just does what it's told. All charging decisions are ultimately made by the LEAF's on-board charger, as that is where the CAN messages originate. SOC is also sent from the car, so the QC could stop charging at a certain % if it wanted to. There is also an elaborate startup test to make sure the insulation and connector integrity are flawless before it will let you start charging.
I arrived with about 45% SOC, as you can see from the bar.
(Excuse the blurry pic, the sun was bright and it was hard to see what I was doing) So here we are about 5 or 6 minutes in, and already up to about 72%, and the charge has already dropped to 78A (~30kW).
So it's been about 22 minutes now, and we are at 88%, but the output is down to 28A (11kW). The display shows 2.9kWh used, but that's definitely not right! We've charged from 45% to 88%, or 43% of the LEAF's 24kWh pack. That should be reading at least 10kWh! It also pessimistically indicates about 32 minutes remaining.
It continued to taper, reading about 8A (~3kW) when at 98% SOC. It finished just under 30 minutes total, and indicated (erroneously) a total of 6.2kWh used. This may be an artifact of an incompatibility between the Japanese power system and ours. It's designed to accept 200v 3-phase, and I think it's running on 240v. (possibly 208 if wye connected) I was told that mid-day, when there is lots of sun, sometimes the charger will generate an overvolt error and will not want to start. Probably rise due to the large solar array pulling everything high when it's really cranking.
When I arrived I had 6 bars of battery temperature, and when I left it was reading 7. Not bad for how much energy I crammed into it in such a short time! This means my battery was over 98 degrees, but under 122. Not very much granularity, but this is what were used to with the LEAF. Next time I'll log the actual temperature.
Sadly this charger spends most of it's time collecting dust (and peanut butter), because of Lawyers. It would be nice if we could organize some sort of benefit for Vacaville to help it pay for the new unit, which they would make available to the public.
-Phil
This station is publicly accessible right off I-80, however due to it's lack of UL listing (the Japanese don't typically use UL), some PG&E lawyer deemed it too much of a liability risk to allow the public to actually use it, and most of the time it's shut down. The unit conforms to CHAdeMO specification which is extremely safe and reliable, so it's lack of UL listing is a silly reason to shut it down. The Japanese have their own regulatory/testing system called JET, and I'm sure this unit is JET listed. Do you think TEPCO, also being a public power company, would put it's name on something unsafe? UL listing is not a requirement for equipment in almost all parts of the US, and it's an independent testing lab, that is not affiliated with any government agency.
PG&E submitted a proposal to the City of Vacaville to purchase a new UL listed charger, and if accepted, this unit would be replaced. But Vacaville must pay for it, as PG&E supposedly is forbidden to do this by some regulatory tenet.
The location also contains a decent assortment of other charger types, mainly J1772 Level 2, but some SPI's as well. The parking spaces are covered by a large solar array which provides a nice shade. I suspect this location generates way more power than is every used by EV's!
Ok, on to the fun part!
The handle is physically easy to deal with, it's light and rugged, but admittedly not intuitive. There is a red lever and a big black handle that is very "gas-pumpish", and you have to release/lock the thing with the red lever and then engage the internal connectors using the big black handle. The effort is very low, once you get the order correct. Once charging, a solenoid locks the connector in the car, and will not allow release until you stop the charging. Seems to me, they could have replaced the solenoid with a small motor and then it would have been much simpler to use, and even less force required.
So, within a minute of connecting the handle and pressing start, the amperage shot up to 125a and pretty much stayed there for quite some time. (+/- 1 amp)
The display shows real-time Volts, Amps, and SOC (State-of-Charge) as a percentage bar-graph. It also attempted (poorly) to estimate how long the charge would take. Note the date and time are also way off. I'm surprised it's set at all with the power being off most of the time. (It must have a battery)
The way CHAdeMO works, the QC (Quick Charger) receives commands from the LEAF via a CAN (Controller Area Network) connection every 100ms. These messages tell the QC how many volts/amps to deliver, and the charger just does what it's told. All charging decisions are ultimately made by the LEAF's on-board charger, as that is where the CAN messages originate. SOC is also sent from the car, so the QC could stop charging at a certain % if it wanted to. There is also an elaborate startup test to make sure the insulation and connector integrity are flawless before it will let you start charging.
I arrived with about 45% SOC, as you can see from the bar.
(Excuse the blurry pic, the sun was bright and it was hard to see what I was doing) So here we are about 5 or 6 minutes in, and already up to about 72%, and the charge has already dropped to 78A (~30kW).
So it's been about 22 minutes now, and we are at 88%, but the output is down to 28A (11kW). The display shows 2.9kWh used, but that's definitely not right! We've charged from 45% to 88%, or 43% of the LEAF's 24kWh pack. That should be reading at least 10kWh! It also pessimistically indicates about 32 minutes remaining.
It continued to taper, reading about 8A (~3kW) when at 98% SOC. It finished just under 30 minutes total, and indicated (erroneously) a total of 6.2kWh used. This may be an artifact of an incompatibility between the Japanese power system and ours. It's designed to accept 200v 3-phase, and I think it's running on 240v. (possibly 208 if wye connected) I was told that mid-day, when there is lots of sun, sometimes the charger will generate an overvolt error and will not want to start. Probably rise due to the large solar array pulling everything high when it's really cranking.
When I arrived I had 6 bars of battery temperature, and when I left it was reading 7. Not bad for how much energy I crammed into it in such a short time! This means my battery was over 98 degrees, but under 122. Not very much granularity, but this is what were used to with the LEAF. Next time I'll log the actual temperature.
Sadly this charger spends most of it's time collecting dust (and peanut butter), because of Lawyers. It would be nice if we could organize some sort of benefit for Vacaville to help it pay for the new unit, which they would make available to the public.
-Phil