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I would strongly recommend looking at any generator's output on a scope before connecting it to your $40K+ Bolt.

I can almost guarantee that any damage done to your Bolt by a sub-par generator would not be covered under warranty.


You can buy a no-frills scope for $29 on Amazon that is perfectly suited for looking at 120vac waveforms:
https://www.amazon.com/Quimat-Pocket-Size-Oscilloscope-Protective-Assembled/dp/B07GRK38MS/ref=sr_1_3?ie=UTF8&qid=1543419394&sr=8-3&keywords=dso138+digital+oscilloscope










Here's the output from my 2,000 Watt inverter generator (under load)on the above scope ...
I would feel comfortable charging the Bolt from this generator.















Here's the terrible output from a standard backoffice grade UPS....
I tried my Mod-Con boiler with it's ECM circulator pump on this UPS... the pump was singing!!
If I had run it for more than a couple of minutes it probably would have burned out the pump and or boiler control board.



For comparison sake, what does this scope show you when you plug it in the wall at home?
 

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The interesting thing is that both of those appear to be "modified sine wave" type inverters, though the former might call itself "pure sine wave" those sure appear to be steps in voltage along the wave form.
I think the very fine "steps" you're seeing in the first sine wave are due to the resolution of the display more than an indication that the waveform isn't truly smooth.
 

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Gold stars for Greg and Sean!


I just plugged the same scope into a standard wall outlet in my home, used the same phone to take the photo:


 

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Gold stars for Greg and Sean!


I just plugged the same scope into a standard wall outlet in my home, used the same phone to take the photo:


OK that's even more interesting, I have a proper Oscilloscope I am thinking of pulling out and checking out the waveforms from my various UPSs (price range from $80-$1200), of course it's been about 28 years since I've actually used one so I may need to re-learn how.
 

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OK that's even more interesting, I have a proper Oscilloscope I am thinking of pulling out and checking out the waveforms from my various UPSs (price range from $80-$1200), of course it's been about 28 years since I've actually used one so I may need to re-learn how.

I thought about doing the same thing. 25 year-old Goldstar 20MHz analog. Dual channel. I hope the electrolytics haven't dried out.



Me too....:eek:
 

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Gold stars for Greg and Sean!
I just plugged the same scope into a standard wall outlet in my home, used the same phone to take the photo:
Rob, if you get a chance, what does the waveform look like under load somewhat like the EVSE load, maybe a space heater or something like that?
 

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Rob, if you get a chance, what does the waveform look like under load somewhat like the EVSE load, maybe a space heater or something like that?

I'll have to see what I can come up with... how about a heat gun or one of my wife's blow driers?
I think she has a 1,500 watt gun?
 

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OK that's even more interesting, I have a proper Oscilloscope I am thinking of pulling out and checking out the waveforms from my various UPSs (price range from $80-$1200), of course it's been about 28 years since I've actually used one so I may need to re-learn how.
Sounds like a great project!


If you do it... maybe I'll break out my tektronix scope too... haven't used it in probably 10+ yrs either.
 

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Sounds like a great project!


If you do it... maybe I'll break out my tektronix scope too... haven't used it in probably 10+ yrs either.

Wow! We used Tektronix in our R&D lab in the '80s, along with a few HPs. Mostly Tek 465's, but we had a couple of 7000 series with the module plug-ins. The digital storage plug-ins were swapped in as they became available.


It always cracks me up when I see sci-fi movies from the '60s that show "astronauts" controlling their "space ship" by twisting the knobs on an oversized old oscilloscope.
 

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I'll have to see what I can come up with... how about a heat gun or one of my wife's blow driers?
I think she has a 1,500 watt gun?

FWIW, I used a heat gun with a 900W and a 1200W setting as a test load on my emergency inverter setup. 900W worked fine, but the Bolt's DC-DC couldn't keep up with 1200W on the inverter load side.
 

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Wow! We used Tektronix in our R&D lab in the '80s, along with a few HPs. Mostly Tek 465's, but we had a couple of 7000 series with the module plug-ins. The digital storage plug-ins were swapped in as they became available.
I got this one used on ebay back when it was fun hacking DSS IRD's. IIRC it was under $150 and worked perfectly.




It always cracks me up when I see sci-fi movies from the '60s that show "astronauts" controlling their "space ship" by twisting the knobs on an oversized old oscilloscope.
Remember the iconic opening from the original "Outer Limits" series?
Just a simple scope screen... but it worked (along with the "Control Voice" and the ominous theme music).


 

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I got this one used on ebay back when it was fun hacking DSS IRD's. IIRC it was under $150 and worked perfectly.





Remember the iconic opening from the original "Outer Limits" series?
Just a simple scope screen... but it worked (along with the "Control Voice" and the ominous theme music).

Yup. I almost mentioned it, too. Someone was twisting the vernier dial on a signal generator to stretch and shrink the sine waveform. I can still hear that guy's voice in my head. Loved that show. "The Zanti Misfits" scared the [email protected] out of me! (I was seven, so cut me some slack.)



https://en.wikipedia.org/wiki/The_Zanti_Misfits
 

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^ loved that series.... it was very ambitious even by 1960's standards. It was produced on a shoestring budget too as I recall.

Lots of future stars cut their teeth on Outer Limits and The Twilight Zone.


You knew you were in for a sci-fi treat after that one of a kind opening sequence!
 

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FWIW, I used a heat gun with a 900W and a 1200W setting as a test load on my emergency inverter setup. 900W worked fine, but the Bolt's DC-DC couldn't keep up with 1200W on the inverter load side.
Can you tell us a bit more about this test. What does it look like when the Bolt's DC-to-DC converter “can't keep up” (i.e., how could you tell?)
 

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You should be able to charge a Bolt EV using a gasoline generator provided you use the correct type of generator. I would presume you would want to do a level 2 charge system; level 1 just takes far too long and level 3 is very expensive—the charge system and the required 50kW generator would cost almost as much as a Bolt and be almost as large and heavy.

A level 2 charge system provides 7.5kW or put another way, 32A at 240V. This is equivalent to a household clothes dryer outlet or what is often called an “RV Power Outlet”. With this power, you gain about 32 miles per hour of charge so to completely charge an almost empty Bolt battery requires about 7 hours. So this defines the size of gasoline generator you need to use. I would use a generator rated at 8000 Watts continuous. That’s a large generator, perhaps $1000, 250 pounds and the size of a small mini-dorm refrigerator. If you use something smaller, like a 3000 Watt generator, your charge time will go longer proportionally. Also, you need to look at fuel usage. Many generators will specify they can run for 6 or 8 hours on a tank when delivering 50% load. So if you use an 8000 Watt generator at full load (to fully charge the battery in 7 hours) you will have to refill the fuel tank once or twice during the charge cycle. Also, be sure the generator is rated to run continuously at full load for that long a time and won’t overheat.

Generators put out a “sine wave” which is the same kind of waveform you get from an electric utility (which also is produced by a generator—a very large one). Conversely, an “inverter” delivers a square wave or perhaps a “stepped square wave”. This may also be referred to as a “dirty” signal and can cause problems with many loads. The charging system inside the Bolt expects a “pure” sine wave and may have problems with power that is not a sinewave, such as an inverter delivers. I would certainly not use a generator that did not deliver a clean sinewave. How clean or pure the waveform is, that is how close to a perfect sinewave is specified by how much “Total Harmonic Distortion” is present. 0% is perfect and you won’t find nor do you need that clean. 5% THD is clean enough and good generators will have a number like that.

So to summarize, you need a 8000 Watt gasoline or propane generator (not an inverter-type), a level 2 charge station, and the proper AC connector or adapter to connect the two. The most common type of AC connector is an NEMA 14-50 but there are adapters to the other NEMA connectors used for a 240V 30, 40, or 50 Amp circuit.
 
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