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Too be electrically "correct" should some type of a selector switch be inserted between the two plugs so you can't have both plugs live simultaneously?
You can have more than one receptacle if the circuit is sized accordingly.

NEC 625.40 Overcurrent Protection.
Overcurrent protection for feeders and branch circuits supplying electric vehicle supply
equipment shall be sized for continuous duty and shall have a rating of not less than 125 percent
of the maximum load of the electric vehicle supply equipment. Where noncontinuous loads are
supplied from the same feeder or branch circuit, the overcurrent device shall have a rating of not
less than the sum of the noncontinuous loads plus 125 percent of the continuous loads.
 

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Oh well, the likelihood of my EV becoming non-functional due to a power outage is still pretty low....
Seems to me that if you have a fully charged Bolt and the power goes out, you are within 238 miles of being able to charge. For me, the nearest DCFC charger is about 20 miles, so I never worry about charging my Bolt while there is a power outage. Usually, I keep the car at about 80% of full charge. My average drive is 53 miles, so I don't see a problem. Most people will be in a similar position, I would have thought.

The big deal these days is to think about running your house off the Bolt EV battery, during a power outage. GM does not allow for this, yet, and I am not sure I would want to do it anyway, but there are those out there that think its a great idea. I understand a Nissan LEAF can do it, with equipment sanctioned by Nissan. I have not gone into it, because I don't have a LEAF.

It seems to me that a 60kWh battery is hardly enough to power a house more than a day or two. I use an average of 42 kWh per day. As I can run my propane generator for a couple of weeks with no problem, use of a battery to power the house is a non-starter.
 

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Wow! Very pretty. I love well-done wiring.
Is that 6# wire?
Yes, what you're seeing is #6 wire. I will upload a completed picture tomorrow so you can see it done. The wire that feeds this sub-panel is #3 . I have a subpanel for my basement remodel, and I fed that with #2 . That is completed, all done unlike the picture you saw of the charging circuit. I attached that completed sub-panel picture to this message, of my basement sub-panel.
 

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Seems to me that if you have a fully charged Bolt and the power goes out, you are within 238 miles of being able to charge. For me, the nearest DCFC charger is about 20 miles, so I never worry about charging my Bolt while there is a power outage. Usually, I keep the car at about 80% of full charge. My average drive is 53 miles, so I don't see a problem. Most people will be in a similar position, I would have thought.

The big deal these days is to think about running your house off the Bolt EV battery, during a power outage. GM does not allow for this, yet, and I am not sure I would want to do it anyway, but there are those out there that think its a great idea. I understand a Nissan LEAF can do it, with equipment sanctioned by Nissan. I have not gone into it, because I don't have a LEAF.

It seems to me that a 60kWh battery is hardly enough to power a house more than a day or two. I use an average of 42 kWh per day. As I can run my propane generator for a couple of weeks with no problem, use of a battery to power the house is a non-starter.

I've equipped my Bolt with a 125A Anderson connector off the aux battery. I should be able to power essential loads of ~5kWh per day for at least a week. A typical Energy Star rated fridge should only require about 2kWh per day.
 

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I forgot to post the final wiring for the project. It was a simple install. How the capacity chart pulls off getting six #3 wires in 1 1/14 conduit is beyond me. It was a pain getting 3 in it with all the bends. I used enough lube to make a Fluffer jealous.
 

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If I'm not mistaken, my Chevrolet Bolt EV Owners Manual says not to charge the Bolt EV from a household standby generator. I assume it is because the generator's output is not a perfect sine wave. My guess is that while it may work in the short term there may be long term side effects to the Bolt.
 

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If I'm not mistaken, my Chevrolet Bolt EV Owners Manual says not to charge the Bolt EV from a household standby generator. I assume it is because the generator's output is not a perfect sine wave. My guess is that while it may work in the short term there may be long term side effects to the Bolt.
In the 2019 manual, I could not find that reference. The Generac module you see there is a smart management module which I have set to lock out the charger, but it is designed to automatically shed a load under the following conditions:

<58 Hz for 3.5 seconds.
<50 Hz for 1 second.

My 22kW generator is wired for the whole house, so in order for me to lockout/shed the EV charger, I bought the SMM you see in the picture. I truly believe the generator can safely take on the load of the charger, I have no doubt, but my Bolt is not my only vehicle so in a extended power outage, I have plenty of options.
 

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I'd take a real close look at the generators output with a scope before connecting to the Bolt.


Being that you can get a scope for under $30 now, there's no excuse not to check.
An earlier post recommended that I look at the power. So I bought the scope below. Not sure how accurate it is, I've read that not all meters are 'alike.' In any case, I checked the frequency at an outlet, and it was a steady 59 Hz on utility. I transferred the house to generator and it was between 59 and 60. I ran the tap water/faucet long enough to get the well pump to kick on and there was no change in the frequency during that cycle. I didn't walk around and turn big appliances on, I was fixated and watched the meter graph/readout. My generator is 3 years old, and it's more than double the size of what my typical power load is. It's 22kW.

My installation has the charger locked out, but I believe it would be fine to 'charge' my Bolt with the JuiceBox off of generator power. I spend extra money for the Smart Management Module (SMM) in the picture so I could, on the fly, reverse the lock out and put the charger on gen power if the circumstances dictated it. 'Dumb' management modules would have been less than half and would have simply shed the circuit without giving me any manual control. This SMM can make a logic decision if the car is too much for the generator. But I understand from the concern here it's not just overall load and capacity but a concern about how clean the energy is. I do know that these generators have come a long way in providing 'better' power, for what that's worth.
 

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I forgot to post the final wiring for the project. It was a simple install. How the capacity chart pulls off getting six #3 wires in 1 1/14 conduit is beyond me. It was a pain getting 3 in it with all the bends. I used enough lube to make a Fluffer jealous.

"I used enough lube to make a Fluffer jealous."


Now *that's* funny! >:)
 

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On page 248 of my 2018 BOLT EV Owner's Manual:
"Do not use portable or stationary backup generating equipment to charge the vehicle. This may cause damage to the vehicle's charging system. Only charge the vehicle from Utility supplied power."

Does this statement appear in the 2019 Owner's Manual?
 

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On page 248 of my 2018 BOLT EV Owner's Manual:
"Do not use portable or stationary backup generating equipment to charge the vehicle. This may cause damage to the vehicle's charging system. Only charge the vehicle from Utility supplied power."

Does this statement appear in the 2019 Owner's Manual?

The same warning is on page 253 of the 2019 Bolt owner's manual.



Sent from my iPad using Tapatalk
 

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Discussion Starter #34
I'm jealous of you 22KW generator....

Back to my limited 10KW issue, I was thinking of running 240V off of a 20AMP breaker on my transfer panel to a NEMA 14-20 receptacle so I could at least use my Chevy EVSE at 240V in a power outage situation. Based on my worst-case scenario, I should have 12AMPs to play without exceeding my maximum running load.

Does that sound reasonable (ignoring the users manual warning, of course)?
 

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I wonder what issue Chevy has with running off a good quality generator. There is more to power quality than just frequency and voltage. Total Harmonic Distortion (THD) is an issue for a lot of electronic systems. Generally, the recommendation is to stay below 5 or 6% THD when running electronic equipment. Many less expensive portable generators run as high as 20-25% THD at full load (the Generac GP series of portable generators is one example, though their higher-end portables are much better). The better inverter-based generators have a "True Since Wave" output and put out higher-quality power than the electric grid in some locations.

I would think that the Bolt would have a hard time distinguishing between a quality inverter-based generator and the grid (or even a quality non-inverter generator with less than 5% THD). Are they just being on the safe side and telling everyone to avoid them, so they don't have to spell out exactly what conditions/types of generators are acceptable?
 

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I believe they are being on the safe side and they are accepting to the fact that there are as many generators out there as there are Tom, Dick and Harry's. Many of them work for sheet and many owners don't even realize their generator is not within spec. Chevy is taking the safe road, no pun intended. I have a Generac 22kW air cooled Guardian, their cheapest line and it's not the fancy Guardian home model that was designed for sensitive equipment. I have tested my car charging with my generator for hours and no issues. I also installed an electronic overload lock-out module just in case. I have deliberately tried to overload my generator while charging. Not in an effort to 'break' anything, but to test the lockout mechanism. I tried to get my well pump and 5 ton AC to kick on at the same time while both ovens were running, every light I know that exists 'on' and a load of wash going. It didn't overload the generator, nothing shed. It's programmed to shed the car first and the AC second.
 

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@ZoomZoom - I saw your posts about your installation above. Impressive.

I also suspect the "no generators" bit was a matter of being on the safe side by Chevy/GM. I know the good inverter-based generators make very clean power, and many cases better than the grid. I can't imagine how any electrical appliance would even be able to tell they are on such a generator, let alone have problems with it (assuming the generator is properly installed and run well within it's capacity. I think I'd be inclined to limit the charge rate to something below the generators stated continuous load, even if it was the only load on the generator.)
 

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@ZoomZoom - I saw your posts about your installation above. Impressive.

I also suspect the "no generators" bit was a matter of being on the safe side by Chevy/GM. I know the good inverter-based generators make very clean power, and many cases better than the grid. I can't imagine how any electrical appliance would even be able to tell they are on such a generator, let alone have problems with it (assuming the generator is properly installed and run well within it's capacity. I think I'd be inclined to limit the charge rate to something below the generators stated continuous load, even if it was the only load on the generator.)
Generac has a lock out/shed module that is called an SMM. I bought it for the sole purpose of my EVSE project. The specs of the SMM would lead you to believe that it has the ability to lockout a load for the sole reason of the house being on GEN power. Not for an overload situation, just for the mere fact you are on GEN. Well, even though the instructions say that, it doesn't. The SMM's ability to shed a load based on GEN presence was based on detecting a change in the Hz, to below 58. Well, my generator and many keep the Hz at 59 or better and my SMM will not shed the EVSE. The other way the SMM will shed a load is at a drop of voltage .... aka the GEN is overloaded. After working with a service dealer and Generac, they 'found' a service bulletin written in 2017 that says the auto-lockout/shed ability of the SMM was not what it was intended for.
 

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Generac has a lock out/shed module that is called an SMM. I bought it for the sole purpose of my EVSE project. The specs of the SMM would lead you to believe that it has the ability to lockout a load for the sole reason of the house being on GEN power. Not for an overload situation, just for the mere fact you are on GEN. Well, even though the instructions say that, it doesn't. The SMM's ability to shed a load based on GEN presence was based on detecting a change in the Hz, to below 58. Well, my generator and many keep the Hz at 59 or better and my SMM will not shed the EVSE. The other way the SMM will shed a load is at a drop of voltage .... aka the GEN is overloaded. After working with a service dealer and Generac, they 'found' a service bulletin written in 2017 that says the auto-lockout/shed ability of the SMM was not what it was intended for.
That's a bummer. The functionality you were looking for seems as though it would be a handy option to have. If I had a generator with "dirty" power, it would be nice to set it up to lock out sensitive loads, or aeven any large loads that were not critical.
 

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That's a bummer. The functionality you were looking for seems as though it would be a handy option to have. If I had a generator with "dirty" power, it would be nice to set it up to lock out sensitive loads, or aeven any large loads that were not critical.
Yes, was sad and on the verge of upset when they sent me the bulletin. The darn thing has a switch called; lockout. If you turn the switch on, it sheds the load when on GEN. If you turn the switch off, it will only shed the load if the generator was overloaded. I put the SMM in because it was high tech. The transfer switch also has relays and does it's own load shedding based on time delay or overload. Generac sells a 'dumb' management module, it's a PMM and that is a simple relay that the transfer switch could control. It was half the price, didn't want to buy it because the 'new' SMM (Smart) model existed. Buyer remorse. I ran extra cables, so I could use the PMM. But darnit, wanted the high tech solution.
 
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