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That is service mode. Just lets them power the vehicle on and run diagnostics. I guess it is sort of an accessory mode since you can operate the accessories and not drive, not sure if there is any harm in leaving it in that mode for a long time. I don't know if the car will charge the 12v battery in this mode or if it only runs off the 12v battery in that mode. I suspect it would not charge the 12v battery though but I don't see anything in the manual that states one way or the other.
I tried this with a mutli-meter. It does not charge the battery in this mode.
 

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1500 watts is more than enough to run wifi said:
Good info! To tune it a little more finely, I checked my refrigerator (25 cu ft LG door bottom freezer). It draws 115V 5.2Amps, that's 598 Watts. That leaves enough capacity to run some lights and hook into the heating system (not A/C) and keep the house warm in winter.
 

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I just went through this scenario as you probably saw in my other thread. I just used a 750W unit I was able to pick up in a neighboring town. Ran the fridge, battery chargers for power tools (was using the flashlight) and two laptops off 750W no problem. Oh also ran a HEPA air filter which uses up to 400W. The latter made an odd sound off the modified sine.
 

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Good info! To tune it a little more finely, I checked my refrigerator (25 cu ft LG door bottom freezer). It draws 115V 5.2Amps, that's 598 Watts. That leaves enough capacity to run some lights and hook into the heating system (not A/C) and keep the house warm in winter.
careful when estiamtely fridge usage - normal usage is pretty manageable - but if your fridge is frost free - the defrost cycle which only occurs every few days will take a much larger amount of power - but for most usage fridges don't use more than 300 watts - but they can be as high as 1200 watts for the defrost cycle.
 

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This was one of the things that bothered me coming from a Nissan Leaf, BUT: I believe that the equivalent of accessory mode is leaving it in Park. There are two indications for this - it draws much less power, and doesn't activate the pedestrian alert sound, both suggest that the entire drivetrain hasn't been activated.

There isn't a accessory mode for the Bolt, you just have to turn it on and while it isn't moving it is basically in accessory mode.
 

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If the average household uses 900 kWh per month then it uses about 30kWh per day and the Bolt's battery would only last 2 days.
I wouldn't consider living with everything you normally use in an emergency situtation
a good idea :D I'm sure if you use the power sparingly you could go at least a week, IMO!
 

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If you found a plug to use straight off the converter you could bypass the12 volt system
and use AC voltage >:)

Run, Forest, RUN.
 

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Good thing to know as well is that the 12v battery is the "starter" for the car. When you hit the power button it is using the power from the 12v battery to initiate all the cars subsystems and activate the actual battery. So if for some reason the 12v battery dies, you can't start your car.
QUOTE]
Learned this the hard way with a Plug-in Prius. 1st week with a brand new car with fully charged drivetrain battery would not start because we didn't know how the light switch auto-off mode works. Left it overnight with driving lights on - wont start. I tried everything before wife said read the manual. Oh, there is a charge tab behind a cover to jump start it. Technically it does not make sense to have a redundant little battery which is common source of failure. Why not just tap some amps from the big battery but I don't know much bout EV. There must be a good reason.
Can someone enlighten me on this?
 

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A tiny milli-ampere load over a long enough time period will drain any battery, and so you can imagine that putting the low level power drains from the modules, BMS, and other goodies on a 12V battery that cost a few hundred to replace might be a good idea vs tapping the high voltage battery - one that if over-discharged would plate metallic lithium onto the battery electrodes, send series cells into reverse polarity if charging was attempted in such a state, etc - and would cost thousands to repair after such a mishap. Many of these electronics do not have a hard contactor or physical relay disconnect-like switch, but rather just enter a very low power mode, much like the ECM/PCMs in modern ICE cars. Over time, this would be a problem as the state of charge got lower and lower until eventually permanent damage was done.
 

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Why not just implement a battery voltage or wattage draw monitor and just isolate the drive battery pack when draw down to some cut-off voltage? Or have a wattage counter to limit backup time. Essentially when the set draw-down criteria is exceeded the car goes to isolation mode and a jump start will be needed. I mean my phone can warn me when I am at low power and even goes to extreme power safer mode. Does not seem that hard to implement.
 

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I'm sure that such a design is theoretically possible, but we just don't have the full picture of all the criteria they work from while designing the car. Maybe it's due to having a lot of 12V common of the shelf parts they decided to go this route, or maybe it is harder to achieve a good and low standby/idle current draw for the electronics when you step down for the low voltage electronics from ~400V DC vs. doing the job with 12V DC. I'm sure there is a lot of momentum behind 12V design at the moment as a sort of "ICE vestigial tail" - we may well see 12V fade entirely from the landscape over time.
 

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Good thing to know as well is that the 12v battery is the "starter" for the car. When you hit the power button it is using the power from the 12v battery to initiate all the cars subsystems and activate the actual battery. So if for some reason the 12v battery dies, you can't start your car.
QUOTE]
Learned this the hard way with a Plug-in Prius. 1st week with a brand new car with fully charged drivetrain battery would not start because we didn't know how the light switch auto-off mode works. Left it overnight with driving lights on - wont start. I tried everything before wife said read the manual. Oh, there is a charge tab behind a cover to jump start it. Technically it does not make sense to have a redundant little battery which is common source of failure. Why not just tap some amps from the big battery but I don't know much bout EV. There must be a good reason.
Can someone enlighten me on this?
The DC to DC converter is a big vampire drain if left on all the time. The contactors (which close the circuits for the HV battery) are operated by 12V.
 

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Dc to dc step down converters are common place. Cost is low as long as power output is small, think <1 amp. I just did a quick calc, to supply .3A 12V overhead would take years to draw down a 60KWh battery. There must be a architectural reason.
 

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You have to design/engineer for a low or nearly empty battery when parked long duration, not a full one. Find a dc-dc converter that does 400Vdc to 3.3vdc and see what the efficiency is in the tens of milliamp range, and then compare it to a 12vdc to 3.3vdc step down regulator, there may be a difference. Then, you have to account for a true no-load off condition for the HV, which means you need to take into account the additional load of the contactor/relay coil being pulled in at all times while the car is in the off position while parked. On the 12V battery case, you don't have to care enough to design in a physical relay disconnect, because the worst case scenario is an order of magnitude lower impact, just a dead 12V battery. I'm sure they do a series of product design cases when all this is being considered.
 

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Did a google search. The Leaf uses the main battery to heat the battery so it is definitely possible to tap off the big 400-600V battery for things. In fact some EV 12V batteries are tiny. But the best reasons I found are:
1) Safety. Emergency responders do not have to cut high power lines just the 12V battery feed.
2) Cost - dinosaur 12v lead acids are cheap.
 

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I wish the accessory mode wouldn't allow you to switch to drive and move the vehicle.

The other day I had my wife check to see if I took the keys with the car in Park, if she could move it. I believe it told her the keys were gone, but allowed her to drive away.
 

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The other day I had my wife check to see if I took the keys with the car in Park, if she could move it. I believe it told her the keys were gone, but allowed her to drive away.
If you turn the car ON, the keys must be there. If you then walk the keys away from the car without turning it off, the car will stay ON. It does that by design, because if the battery in your key fob fails while you're driving down the freeway at 70 MPH you really don't want the car to shut down on you.

If you don't want someone to drive away with the car, then turn it OFF before you leave it.
 

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There is presently a high risk for an epic ice storm with high winds in Southern Ontario that could lead to long-term power outages. In preparation I have tested my backup electricity sources including my portable generator and my 1500W inverter which is powered by my Bolt EV's 12V battery. The photo shows the inverter connected to the Bolt EV. It works great!

My furnace runs on natural gas but requires up to 320W to run the blower, electronics, and thermostat. My fridge and freezer each need less than 200W, so I will be able to connect all three to the inverter at the same time. Having to cycle my Bolt off and on every couple of hours is a pain, but at least it will provide 3 or 4 days of power for heat, fridge, and freezer if required.
 

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