Legacy Blink Charger - Derated to 24A but charging at 16A?

[kylemcooper]

Hi Everybody. After being a proud Volt Owner for 3 years, I made the plunge earlier this week to a pure Electric 2014 i3 BEV. I was really torn between staying with a REx platform, but in the end decided to go BEV, based upon some of my previous Volt Stats and overall lower cost. Living in the oil capitol of the world (Houston), a lot of people's heads fall off when they hear that. For the four or so days I've had it though, it's been a great car.

As a Volt Owner, I had a Blink EVSE installed as a part of the "EV Project" by now defunct Ecotality. As many are aware on here, there have been issues with those cord sets not being properly rated for constant 30A usage (i.e. melting), and so Blink derated them to 24A before they went bankrupt. There are replacement cords available, which I am contemplating. My question though for the group is, while i see that the display is technically limiting it to 24A, it seems like the i3 is still only charging at 3.3kWh (16A). I double checked in iDrive that it is set to maximum for Level 2. How does the negotiation work between EVSE and the actual onboard car charger work, relative to what rate it agrees to charge at? It seems that even though 24A is available, it is downgrading to 16A. What rates are others who are utilizing derated Blink units seeing?

 

[jadnashuanh]

The EVSE outputs a pilot signal that announces to the EV how much power is available, and then the car adjusts itself to draw what it wants to, up to the max either it or the EVSE can provide. Depending on where the i3 was in battery state of charge, it may not draw the maximum available (it tapers off at the end of the charge, and ramps up in the beginning, especially if the batteries are hot at the moment either from being driven awhile or because of the weather). What voltage and current is that EVSE actually supposed to be capable of? If it was adjusted, the pilot signal may be out of calibration.

 

[kylemcooper]

The EVSE outputs a pilot signal that announces to the EV how much power is available, and then the car adjusts itself to draw what it wants to, up to the max either it or the EVSE can provide. Depending on where the i3 was in battery state of charge, it may not draw the maximum available (it tapers off at the end of the charge, and ramps up in the beginning, especially if the batteries are hot at the moment either from being driven awhile or because of the weather). What voltage and current is that EVSE actually supposed to be capable of? If it was adjusted, the pilot signal may be out of calibration.

Thanks... I didn't think about the SOC affecting it, but I believe it was around 65% to 75% when I plugged in. Blink charging summary stated it used 6.2 kWh over 1:42. The Blink hardware is supposed to be capable of 240v/30A, but set to 24A due to firmware refresh from Blink.

 

[jadnashuanh]

If you really have 240vac, power is volts*amps...so, 240*24=5760/hour watts. If your input voltage is 230v, in an hour, that's 5520W. Depending on the SOC, as the car gets above about 80%, it starts to slow down the charge rate.

 

[TonyWilliams]

If you need to replace the plug and cable from the original (and poor quality) REMA brand assembly, we have our J-Plug and cable that is 40 amps capable. We can custom build these with any length cable:

http://shop.quickchargepower.com/J-Plug-J1772-40-Amp-Plug-Cable-Assembly-JPC40A.htm

As to the pilot signal from the Blink, I would just replace the entire guts with an OPENevse v2.5

http://store.openevse.com/products/openevse-plus-v2

 

[kylemcooper]

If you really have 240vac, power is volts*amps...so, 240*24=5760/hour watts. If your input voltage is 230v, in an hour, that's 5520W. Depending on the SOC, as the car gets above about 80%, it starts to slow down the charge rate.

Yes, 5760 or there about is what I was expecting. Outside of one day in the last week and half, I haven't been at 65% or lower SOC (haven't had any longer trips yet), so the extra timing really hasn't mattered anyhow. I will run it down a bit when I can, and see if it is more adaptable with a much lower SOC.

 

[jadnashuanh]

Two issues...the EVSE's pilot signal may or may not be adjusted properly so it may not be telling the car the proper power that is available; or, the car may not want the full amount depending on internal temperatures or the SOC of the batteries. Plus, it can take a few minutes for the car to ramp up - IOW, it may not jump immediately to full capacity.

If you were in Europe, you may not have purchased the bigger on-board charger, and couldn't get that full amount anyways.

 

[kylemcooper]

Two issues...the EVSE's pilot signal may or may not be adjusted properly so it may not be telling the car the proper power that is available; or, the car may not want the full amount depending on internal temperatures or the SOC of the batteries. Plus, it can take a few minutes for the car to ramp up - IOW, it may not jump immediately to full capacity.

If you were in Europe, you may not have purchased the bigger on-board charger, and couldn't get that full amount anyways.

I'm in the states (Houston, TX) and it has charged at 6.6kWh from the ChargePoint at the BMW dealer, so I know the onboard charger can accommodate. I think as you mention my i3 has just been sipping rather than chugging given its high SOC.

Thanks.