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Effects of Communication Protocol on Bolt EV Charging Efficiency

5107 Views 5 Replies 4 Participants Last post by  Jeff N
Someone was kind enough to point out to me that Tesla and CHAdeMO equipped cars actually use a different communication protocol than the Bolt EV (CAN bus versus IEEE.1901 respectively).

My question is, could that affect charging efficiency? I know that CAN has to run through the car's ECU, but I'm not sure whether that would add additional parasitic losses. This question is probably more loaded and involved than I think, but I thought I'd ask anyway.

*I just noticed that we actually have a dedicated "Charging" forum. Please move this post if that is more appropriate.
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I thought in the US the Tesla supercharger connector was a modified version of the SAE Type 2 plug and in Europe the standard Type 2 Mennekes plug.

In any event, I can't see why a communication protocol would affect charging efficiency. It's just signaling.
Yes, the US Tesla plug is physically just an SAE J1772 (IEC Type 1) in that it uses the same pins with the same basic layout and pin assignments but in a different plug shape. Also, the 2 power carrying pins on the Tesla are larger because they are used for both AC and DC charging whereas the SAE plug uses a separate pair of larger DC pins for the CCS variant of the plug. Tesla also uses the same AC analog charging protocol as J1772 which sends a sine wave over the "control pilot" pin at a frequency that identifies the EVSE's maximum allowed charging current. However, Tesla and J1772 use different digital charging protocols for DC charging even though they modulate the data over the same pilot pin. Tesla uses CAN bus messaging while J1772 uses the same basic messaging protocols (IP/UDP/TCP) used by the Internet.
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