xsnapshot
Posts: 4
Joined: Thu Feb 18, 2021 12:06 pm
Delivery Date: 18 Feb 2021

Re: 2020 NIssan leaf 12v battery

Thu Feb 18, 2021 1:51 pm

After reading that thread, (which I haven't seen my post get attached to yet), I have an additional question.

If the positive lead is a fused wire coming off the + battery terminal, and the negative goes to a chassis ground, where does the inverter ground go? If you're using it as a mobile power station, are you supposed to get a metal rod out and stick it in the earth and connect? Not a big deal to leave it off in this case? Just curious what actual experiences you all are having.

Thanks!

knightmb
Posts: 673
Joined: Mon Jan 12, 2015 7:41 pm
Delivery Date: 26 Feb 2021
Leaf Number: 306291
Location: Franklin, TN

Re: 2020 NIssan leaf 12v battery

Fri Feb 19, 2021 9:53 am

xsnapshot wrote:
Thu Feb 18, 2021 1:51 pm
After reading that thread, (which I haven't seen my post get attached to yet), I have an additional question.

If the positive lead is a fused wire coming off the + battery terminal, and the negative goes to a chassis ground, where does the inverter ground go? If you're using it as a mobile power station, are you supposed to get a metal rod out and stick it in the earth and connect? Not a big deal to leave it off in this case? Just curious what actual experiences you all are having.

Thanks!
Depends on the inverter that you purchase. Some just link the neutral and ground in the inverter and use a GFCI for shock protection. I've seen others that give you a "ground" connection out the back for those purposes and thus the outlet coming from the inverter will show up as a "open ground" on the outlet tester otherwise. For simplicity, find an inverter does the ground/neutral bonding inside the inverter with a GFCI outlet for protection from overload/shock hazard. Then you only need to worry about connecting the positive and negative wires, much simpler. :mrgreen:
2020 Leaf SL Plus

knightmb
Posts: 673
Joined: Mon Jan 12, 2015 7:41 pm
Delivery Date: 26 Feb 2021
Leaf Number: 306291
Location: Franklin, TN

Re: 2020 NIssan leaf 12v battery

Fri Feb 19, 2021 10:19 am

xsnapshot wrote:
Thu Feb 18, 2021 1:51 pm
After reading that thread, (which I haven't seen my post get attached to yet), I have an additional question.

If the positive lead is a fused wire coming off the + battery terminal, and the negative goes to a chassis ground, where does the inverter ground go? If you're using it as a mobile power station, are you supposed to get a metal rod out and stick it in the earth and connect? Not a big deal to leave it off in this case? Just curious what actual experiences you all are having.

Thanks!
I just realize my previous response didn't answer you question directly. The ground on the back of (inverters that have that), should go to the chassis, which if you follow the circuit, actually comes out of the "grounding" part of the outlet. So if something shorts out in the AC side, it can travel to the chassis as the ground for the shortest path. Does mean the chassis becomes "energized with 120v ac" in the event of a short, perhaps in theory but hopefully only long enough for a fuse or breaker to catch it and trip the inverter off.
2020 Leaf SL Plus

arnis
Posts: 1034
Joined: Sat Jan 23, 2016 3:21 pm
Delivery Date: 23 Jul 2014
Leaf Number: 015896
Location: Estonia, Europe

Re: '15 Leaf - Best place to tap 12v system for 1500 watt AC inverter use?

Mon Feb 22, 2021 3:14 pm

14.4V will not have significant effect on 12V battery but is rather desired in case of high load.
Higher voltage = less losses at DC-DC converter, wiring and DC-AC inverter.
Therefore it is actually wise to connect directly to battery terminal. Plus battery will buffer peaks
and lessen the stress for DC-DC inverter. This is what normal lead-acid batteries were actually made for.
Cranking engines. Nowadays just starting HVAC with inrush current :lol:
I suspect 1500W nominal is absolute maximum Leaf will support...with 2000-2500W spikes for few seconds
buffered by that lead acid battery.
Leaf idle draw when stationary is pretty small with almost everything off. Less than 150W AFAIR.

Usually 1500W nominal inverters are rated 3000W. That is their peak value actually.
Short range EVs <30kWh -- Medium range: 30-60kWh -- Long range: >60kWh
Charging: Trickle <3kW -- Normal 3-22kW -- Fast 50-100kW -- Supercharging >100kW

xsnapshot
Posts: 4
Joined: Thu Feb 18, 2021 12:06 pm
Delivery Date: 18 Feb 2021

Re: '15 Leaf - Best place to tap 12v system for 1500 watt AC inverter use?

Thu Feb 25, 2021 7:06 pm

Thanks for the replies!

Arnis, your reccomendation seems to be contrary to what many on this very forum have said. There was the whole thing about NOT connecting to the negative terminal of the battery as there is a current measuring device there?

On it's face, I never understood why you WOULDN'T want the negative there. Wouldn't you want the brains of your car to register a larger draw and push more power to the DC-DC converter to make up for what you're drawing with the inverter?

I've been doing some research into pure sine wave vs modified sine wave. Most everything I want to run is basic stuff like space heater, deep freezer, etc. No computers. However I see the wisdom of having a pure sine wave just in case you DO need to plug something in that's sensitive.

Thanks for any tips.

knightmb
Posts: 673
Joined: Mon Jan 12, 2015 7:41 pm
Delivery Date: 26 Feb 2021
Leaf Number: 306291
Location: Franklin, TN

Re: '15 Leaf - Best place to tap 12v system for 1500 watt AC inverter use?

Fri Feb 26, 2021 8:58 am

xsnapshot wrote:
Thu Feb 25, 2021 7:06 pm
Thanks for the replies!

Arnis, your reccomendation seems to be contrary to what many on this very forum have said. There was the whole thing about NOT connecting to the negative terminal of the battery as there is a current measuring device there?
I forgot to mention, mine is connected the same way, directly inline with the battery instead of the frame. Otherwise, from what I've seen, many points on the frame are not thick enough to prevent the high DC current from doing metal electrical disintegration process on the connectors or frame points that were not designed to allow such a high current load. If you get any salt or anything acidic in the process it speeds it up. To each their own though, good luck! :o
2020 Leaf SL Plus

arnis
Posts: 1034
Joined: Sat Jan 23, 2016 3:21 pm
Delivery Date: 23 Jul 2014
Leaf Number: 015896
Location: Estonia, Europe

Re: '15 Leaf - Best place to tap 12v system for 1500 watt AC inverter use?

Mon Mar 01, 2021 11:38 am

Frame is good enough for many hundreds of amps :)


Pure sine wave is much better for motors, that includes compressors, that includes freezers.
Computers, especially with a power brick, do not care about sine wave as they work on DC anyway.


OK quality (almost) pure sine wave inverter is less than 100€. 1500W nominal.
Short range EVs <30kWh -- Medium range: 30-60kWh -- Long range: >60kWh
Charging: Trickle <3kW -- Normal 3-22kW -- Fast 50-100kW -- Supercharging >100kW

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