How fast does the 12 volt battery charger charge?

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jjeff said:
knightmb said:
LeftieBiker said:
If the vehicle is in Standby mode (dash active, radio active, but not drive-able), it will activate the 12 volt system when the battery gets down to 10.5 volts to charge it back up. This is the mode I use to power up my house for emergency power (so the vehicle can't be driven off by accident). But I keep the charge mode active non-stop by keeping a load of at-least 50 watts going so that the battery never tops off and it stops charging.
I take it your powering a 120v inverter off the 12v Leaf battery and what is it's wattage? On a link somewhere at MNL I saw where it was possible(or maybe a future thought) to power a mains outlet directly from the traction battery. The vehicle in question was a eNV200 and was meant to provide mains power to construction job sites where a noisy smelly generator wasn't wanted.
Personally thats the type of power I'd want, something I could run my house off of for a limited amount of time during a several hour power outage. Of course not the central air or things like a stove or dryer but things like the TV, lights, refrigerator/freezer and maybe water pump for those with a well. Maybe someday it will be reality......
Yes, 120v full sine wave Xantrex (2000 watts), I have two outdoor plugs that run to where the Leaf is parked, I have a special high powered plug wired into the 12 volt system of the Leaf so I can plug directly in, turn on the inverter and start powering the inside of the house immediately. One plug runs to the solar bank, so it charges up the solar bank (which is already tied into most of the house lights, outlets, etc.) and the other plug runs to a single outlet indoors that I can plug extension cords into to reach AC/Computers/Fridge/etc. The only thing the Leaf can't power is the hot water heater, HVAC, and Dryer. Mainly because all of those are 240v appliances (plus too much power draw). Could still use a Microwave oven or hot plate to cook if we really needed to. Even the washing machine could be used for cold water washing. Very handy though, I use to have a rather large generator setup for backup power but now the Leaf does just as well with no extra maintenance (gas, oil, stabilizer, filters, warm up, etc), sold the generator years ago. :D

Had one good test of it during Winter when the power was out all night after a storm. Many people were moving to shelters to keep warm, but our house was the only one in the city with all the lights on, electric heaters to stay warm, and TV + Internet to stay entertained. It really put the Leaf to the test as it was at near max power draw (1500 watts) all night until morning when the power was finally restored. The Leaf was at about 81% charge when it all started and by morning when I woke up, down to 19% before I finally shut it all down to save some power for driving if we needed it.
 
knightmb said:
The only thing the Leaf can't power is the hot water heater, HVAC, and Dryer. Mainly because all of those are 240v appliances (plus too much power draw).
Of those, the water heater is the one which CAN be powered by the LEAF's 12V system. The first step is to replace your resistive water heater with a heat-pump water heater. That will reduce the load from 4500 W to 600 W. Next, you need an autotransformer to create 240 VAC from 120 VAC. That could be permanently wired directly in the line to the water heater using a single-pole 50A breaker and wiring. I have this exact arrangement in place for my well pump, which allows me to run that off of 120 VAC, but I have yet to do that for the water heater. The drawback for doing it with the water heater is that the transformer will draw about 12 W continuously and there will also be additional losses when it is running, particularly if the resistive elements are turned on. (With the well pump, I put the autotransformer AFTER the pressure switch so that the transformer is deenergized when the well is not pumping.)
knightmb said:
Very handy though, I use to have a rather large generator setup for backup power but now the Leaf does just as well with no extra maintenance (gas, oil, stabilizer, filters, warm up, etc), sold the generator years ago. :D
I haven't parted with my generator and all the lovely accoutrements that you mentioned because I use that to recharge the LEAF during outages. This way the generator only runs occasionally, but we have electricity continuously.
knightmb said:
Had one good test of it during Winter when the power was out all night after a storm. Many people were moving to shelters to keep warm, but our house was the only one in the city with all the lights on, electric heaters to stay warm, and TV + Internet to stay entertained. It really put the Leaf to the test as it was at near max power draw (1500 watts) all night until morning when the power was finally restored. The Leaf was at about 81% charge when it all started and by morning when I woke up, down to 19% before I finally shut it all down to save some power for driving if we needed it.
Nice. Good story!
 
Our house has most of the circuits on a second 200 amp panel that is fed by a xantrex xw6048, basically a 6000w continuous 240v inverter fed from a 48v 20 kwh battery bank. I then have a xantrex SW2000 (12v 2000w invterter) that connects to the Leaf, which in turn charges the 48v battery bank via a iota DLS-54-13 at about 750w.

Typically our house consumes less that 750w so I can run a long time this way. The main grid panel feeds the geothermal (we have a natural gas furnace as backup) , EVSE and a couple of other large 240vac loads. The whole system is automatic. We also had the power go out last winter for just about 2 days, when drove home and used the garage door opener, drove in and everything was normal, it was weird to have the neighborhood so dark and we had lights on. Then slowly you could heard the loud gas gensets start up :)

We also have a Honda EU2000i that can power the same iota 48v charger, so that can also feed the battery bank. And in a pinch I have another 10a 48vac charger so I could use them both at once if needed for powering larger loads although the house bank is a great buffer. Oh we also have 3 kw of solar PV that helps out.
 
BrockWI said:
Our house has most of the circuits on a second 200 amp panel that is fed by a xantrex xw6048, basically a 6000w continuous 240v inverter fed from a 48v 20 kwh battery bank.

My "off-grid" setup is also based on 48 VDC battery storage - basically two sets of golf cart batteries - one in the cart and one spare set. However this is only ~15 KWH (maybe 6KWH usable). Out of curiosity, what is your 20 KWH battery system setup?

I have an OEM 48 VDC golf cart (Club Car) charger that works very well - being supplied by the Secure Power Supply of my grid tied SB4000 TL-US (120 VAC in the off-grid mode). Lots of wasted PV capacity in bright sun, but works very well at any wattage production above 600 watts from the panels (surprised by this!). I'd like to get away from FLA batteries (in the cart also), but not convinced of the economics.
 
Our bank consists of eight Trojan L-16P rated at 420 amps each at 6v, so the bank is 420 amps at 48v or just over 20 kwh. Although I try to never cycle it more than 200 amps out or to 50%, at that point I turn on the genset, but that is pretty rare.

I used to have eight AGM 8D's (500 amps at 48v) and really like them, they lasted 8 years, no watering, no venting, no cleaning and they had an amazing ability supply surge current. I could start our air source heat pump and it would hit 48vdc on the surge. Now, even with new L16's the inverter will dip to 45vdc on the surge. But the L16's were 1/2 the cost, now to see how long they last and how long I can stand caring for them again, the previous bank to that was eight T105's.
 
Nubo said:
I wouldn't consider my habits abusive, although I commonly leave the car plugged into the EVSE on days where I don't drive it. This increases the dark-current load on the 12V battery and, perversely, inhibits the car from charging it.

I'm new here, not very educated electrically, and trying to understand this. What is a dark-current load, and why is there a load at all on the battery when it's plugged in and not charging? Why would a non-charging EVSE draw current?
 
When the car is plugged in but not charging, the car regularly checks the status of the connection, to "see" if the EVSE is still plugged n. This uses power from the 12 volt battery.
 
brenton said:
Nubo said:
I wouldn't consider my habits abusive, although I commonly leave the car plugged into the EVSE on days where I don't drive it. This increases the dark-current load on the 12V battery and, perversely, inhibits the car from charging it.

I'm new here, not very educated electrically, and trying to understand this. What is a dark-current load, and why is there a load at all on the battery when it's plugged in and not charging? Why would a non-charging EVSE draw current?

"Dark current": Almost any modern car uses power from the 12V battery, even when parked and shut down. This is typically a small amount of current to power alarm systems, ECU functions, check for signals from the fob, etc... But over time even a very small current can run down a battery. LEAF has a bit more going on too. To counter this effect, it charges the 12V automatically every 5 days or so if not driven. However, when plugged-in there were 2 factors accelerating the dark-current problem, IIRC. First, the vehicle was drawing more current for telematics and secondly the 5-day recharge cycle was being inhibited. I don't know if these issues still persist.
 
knightmb said:
If the vehicle is in ACC mode (just the radio works) then it will run the 12 volt battery to shutdown, no recharge, you'll need a jump to get the vehicle working again. If the vehicle is off, you can run the battery down also, no charging will activate.

If the vehicle is in Standby mode (dash active, radio active, but not drive-able), it will activate the 12 volt system when the battery gets down to 10.5 volts to charge it back up. This is the mode I use to power up my house for emergency power (so the vehicle can't be driven off by accident). But I keep the charge mode active non-stop by keeping a load of at-least 50 watts going so that the battery never tops off and it stops charging.

Finally, if the vehicle is in drive mode, the 12 volt system is active all the time until you drain the traction battery to shutdown.

Is "Standby" mode the same as what the manual refers to as "ON"? My manual only lists the following modes: ACC, ON, READY, OFF and LOCK.
 
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