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[DonTom]

Bringing up Ohm's Law repeatedly, despite the fact that no one asked you to or disagreed with it in any way, is not helping your argument. I am good at diagnosing things. I eliminate variables, whenever possible, until the issue is found. Your willingness to accept potentially garbage data complicates the diagnostic process.

If you're going to keep hammering away at the idea that you have already locked down all the variables and you know better then I'm going to say, "fuck it" and recuse myself. You clearly know better. Figure out his problem I'm clearly just getting in your way. Peace out.

You asked "Yeah I wanna know the rated amps." And I answered it.


Now I wish I didn't.


I will get out of your way, since you do not like my very accurate answers.

[Specter]

For what it's worth.
The 'rated output' listed on chargers can be misleading at times.

Ohm's law and EGO's notwithstanding.

A charging station says, up to 10 KW charge rate.
You go OH GREAT I can charge my bike at 10 KW.  Then find out it only charges at 6 kw.
You wonder WTF.

CCS has a few 'ranges' it operates in -  100 to 500 volts and I think the second is like 220 volt to 1000 volts.
some oddball chargers may pick a value between those but anyways.

The charger says it can do 10KW output.

The charger is  RATED at say 500 volts and 20 AMPS OUTPUT.  The AMPS....THAT is the important thing.

If your battery pack is at 500 volts, then yes, your 500 volts times the 20 Amps gives you the 10 K OUTPUT.

BUT, if your battery pack is say, a nominal 300 volts (Like the Energica), then that same charger, with its 20 AMP OUTPUT,
is only going to give you 6KW of charge rate.  (that would be those 20 amps times your battery voltage of 300 volts)
The current is the limiting factor.

People see, Max output ..and think it's going to automatically adjust to their battery pack, no that's at highest possible voltage the charger is rated for, at highest rated current, NOT adjusting to pump the full KW into your batteries arbitrary voltage.

Just throwing this out there.

Aaron

[DonTom]

For what it's worth.
The 'rated output' listed on chargers can be misleading at times.

Ohm's law and EGO's notwithstanding.

A charging station says, up to 10 KW charge rate.
You go OH GREAT I can charge my bike at 10 KW.  Then find out it only charges at 6 kw.
You wonder WTF.

CCS has a few 'ranges' it operates in -  100 to 500 volts and I think the second is like 220 volt to 1000 volts.
some oddball chargers may pick a value between those but anyways.

The charger says it can do 10KW output.

The charger is  RATED at say 500 volts and 20 AMPS OUTPUT.  The AMPS....THAT is the important thing.

If your battery pack is at 500 volts, then yes, your 500 volts times the 20 Amps gives you the 10 K OUTPUT.

BUT, if your battery pack is say, a nominal 300 volts (Like the Energica), then that same charger, with its 20 AMP OUTPUT,
is only going to give you 6KW of charge rate.  (that would be those 20 amps times your battery voltage of 300 volts)
The current is the limiting factor.

People see, Max output ..and think it's going to automatically adjust to their battery pack, no that's at highest possible voltage the charger is rated for, at highest rated current, NOT adjusting to pump the full KW into your batteries arbitrary voltage.

Just throwing this out there.

Aaron

Yes, the rating on the machine can also be meaningless. For an example, it if has a 70-amp charger on a ten-amp circuit breaker with wiring that is only good for ten amps.


However, in most cases, by far, you can even go a little above the rating of the one on the machine. I have done such many times with J-plugs, but only by a few hundred watts (or a few amps) at the most or the machine will shut down (I have done that also, as my Zeros ignore the pilot signal with my external chargers). I can adjust manually what rate my Zeros charge at.


-Don-  Cisco Grove, CA

[Specter]

DonTom, I have also found that the watt readings on the machines, on the plugs AND on your bike can be grossly off as well.

I have had my bike say Im charging at 3.6 - 3.7 KW   when the watt meter on the charging station breaker is only showing 3400 ish watts... and the J charger itself saying 3800 watts.  BTW my mains wattmeter is revenue grade so yes, it's accurate.

A man with a watch can tell you what time it is, .. A man with two, is never sure.

Aaron

[DonTom]

DonTom, I have also found that the watt readings on the machines, on the plugs AND on your bike can be grossly off as well.

I have had my bike say Im charging at 3.6 - 3.7 KW   when the watt meter on the charging station breaker is only showing 3400 ish watts... and the J charger itself saying 3800 watts.  BTW my mains wattmeter is revenue grade so yes, it's accurate.

A man with a watch can tell you what time it is, .. A man with two, is never sure.

Aaron

I recall hearing somewhere that the "KW" they use for EVs is less than a real true KW. So if that is true, your lower reading is to be expected on the non-EV rated stuff. I only heard this by hearsay, so I cannot say if it is really true or not, or why they would do such BS.


But often the fast charge machines will show a higher rate than your bike screen. But that is not BS, that is because the machine doesn't know about the small loss in the charging cable at these very high currents. So that is normal and truthful other than the EV KW BS as above (if true).


-Don-  Auburn, CA

[theoutsider]

If I can ride tomorrow morning, I think I can get it <20% SOC and I'll try charging again. I'd be happy if I got something in ~7kw range... I am pretty disappointed so far and feel like I dropped too much coin for only a tiny bit more charging capacity over an SR/F. 

To anyone that hasn't purchased a Zero yet, definitely go for the SR/F and forget about the SR. Upgrades are a losing proposition.

[theoutsider]

So I got my bike down to about 24% SOC and headed to a bunch of Volta stations in a local Amazon Fresh. Apparently not all the stations are actually outputting the amount of kw as they're advertise on the PlugShare app. The first station got to 6.1 kw, the 2nd-4th stations maxed out at 5.7-5.8 kw  All of those stations were advertised at 8.43 kw!!! The free Volta stations didn't have a screen to show the rate of charge.

The last station I tried was advertised as a 7.7 kw station on PlugShare and it immediately started charging at 7.4 kw (exactly what I'd expect)!

I think my 9 kw charging setup is working fine. I just need to take the PlugShare advertised capacities with a grain of salt. 

[Specter]

Again...
The  advertised KW are at absolute perfect conditions,  the max cap in battery voltage .vs. the max amps the charger can put out.

Devices will always have a say so on the charging rate based on what they have been programmed to do, which typically will drop the rate at the end.

Just because my plug says I can give you 32A, and even if you program it to give 32A, if your vehicle says I only want 13 amps, guess what?   THIS is also part of the problem as to why CCS charging can be such a pain in the dick to get going properly is because everyone has their own little 'ideas' how and how much their thing needs to be spoon fed etc.  There really at this point IS NO STANDARD !  If my power sender, and your power eater can not agree how big of a spoon full can fit into your vehicles mouth.. the feeding won't start, or it'll trip out when they decide to stop talking to each other because your bike got tired of playing 'airplane' with the charger trying to feed it and is now looking at the shiny things in the corner instead of paying attention to the charger.

Aaron

[theoutsider]

Just a follow-up, I recently installed a Tesla Wall Connector set to deliver 9.6 kw. I charged my Zero SR from 48% SOC and it immediately started charging at 8.6 Kw! It's great to know my new OBC is working and am amazed at how quickly it charges now!

[DonTom]

Just a follow-up, I recently installed a Tesla Wall Connector set to deliver 9.6 kw. I charged my Zero SR from 48% SOC and it immediately started charging at 8.6 Kw! It's great to know my new OBC is working and am amazed at how quickly it charges now!

The max rating of J-1772 machines vary greatly. They send a "pilot signal" to your bike's charger to reduce its rating to whatever the charge station can handle. I have seen them as low as 3KW and as high as 14 KW.


And some of those will spit their power if both connectors are used, so you then can only get half of the above ratings.



Tesla Wall Connectors also use the pilot signal, but they are normally a lot higher in capacity than most of the J-1772s. The older ones are often 14KW or 18 KW. The older ones have more power probably because there was not much of an on-road charging system back in those days.


My Tesla wall Connectors are on a 60-amp circuit, which makes them good for 48 amps. 20% less than 60 amps for safety reasons. 240 times 48 amps=11,520 watts max.


The typical J-1772 station can only handle around 7 KW max. Typical for Telsa Wall Connectors (and Tesla Destination stations) is 12KW out here, but I have seen them as low as 8KW and as high as 16 KW.


Every machine has its rating on the screen or on the side of the box. You can also find the ratings on Plugshare. You can only charge at whatever the highest rating of the AC machine is even if the charger in the bike has a much higher rating.


BTW, if you use a Tesla-Tap on the older units, you will probably notice they drop out in five to ten minutes. Do not rely on them. The newer 8 and 12 KW units work perfectly with a Tesla-tap but wait longer with only the Tesla-tap than the 30-seconds most of them claim. Wait two minutes before connecting to bike with only the Tesla-Tap and it will work every time on the 8KW and 12 KW units.


One other issue I have seen is shown here.


-Don-  Reno, NV

[theoutsider]

Thanks for the info Don!

My home unit is attached to a 50 amp breaker unfortunately (can't fit a 60 amp one due to size, otherwise I'd have to add a subpanel at more expense), so I had to set my Tesla Wall Connector accordingly. I'm still super happy with my Wall Connector. My bike only charges at 9 kw and my wife's RAV4 Prime only has a 6 kw OBC, so we're good for now.