Community Forums

GottagoChris · 03-02-2021, 10:16 AM

I would like to install 300ah lithium battery and inverter in the forward garage (interior)behind the (exterior) propane tanks. This would be approx. 16'-18' from the electrical panel for connecting the inverter. A- Is this doable, B- Do I need to beef up the existing wire going from the manufactured installed (exterior) 100 amp battery to the electrical panel? C- Should I install the battery and inverter close to the electrical panel. D- Since the lithium battery is sealed- can I mount the inverter and battery near or next to each other?

Ndrorder · 03-02-2021, 11:06 AM

It is best to keep any wires carrying DC voltage as short as possible. Leave the long runs of wire for the AC voltage.

The inverter and lithiums can be installed close together as the lithiums do not vent explosive fumes.

Move the connection of the existing 100A DC wire to the connect to the lithiums sitting in the forward garage.

Run separate DC wire from the lithiums, through an appropriate sized fuse or breaker, and to the inverter installed close the the lithiums in the forward garage.

Then, run an appropriately sized 120V wire from the inverter to the electrical panel. The inverter should have breakers to protect from overload on the 120V circuit. If not, add one.

Be sure your charger has the capability to charge lithium batteries correctly.

GottagoChris · 03-02-2021, 04:13 PM

Thax for your informative and prompt response. Its reassuring to have guidance with such an intimidating project on my plate. I have a single 300ah lithium battery (with plans to add another 300ah battery as soon as the budget allows), 3500w pure sine inverter(6000w surge), heavy duty 3/8" bus bar, heavy duty shunt, 350amp fuse bar, battery shutoff switch...tying this into shore power electrical box 16-18' away.
What gage 120v wire is BEST for this run? Do I need any other componets to make this system work? The 300ah battery is rated with a 200amp BMS. Is that ok?

astrocamper · 03-03-2021, 08:40 AM

Your batteries BMS is rated at 200 amps. Is that the continuous or surge rating? You will not be able to run your inverter at it's rated amperage with a 200 amp limit on the DC.

I used 4/0 DC cables and 650 amp bus bars on the parts of the DC circuit that involved the inverter/charger.

I kept my inverter in my front pass through storage and the batteries just behind the front pass through storage wall. I used stranded 6/5 SOOW cable between my trailers AC breaker panel and my inverter transfer switch. I ran the SOOW through flexible water tight conduit to protect it along the run. My Victron Energy 3000VA inverter/charger transfer switch is rated at 50 amps and the inverter/charger can do power assist combining input power plus inverter power to handle the larger surges. 8/5 cable would have been OK on the rating but I wanted to reduce voltage drop over the additional path.

My original converter was removed from the system. My original 30 amp power plug cable is routed to a 30 amp breaker, then to the inverter/charger transfer switch before returning to the original house circuit breaker panel.

GottagoChris · 03-03-2021, 11:40 PM

The 300ah battery is rated continuous charge100amp, max discharge 200amp and peak discharge 400amp.

GottagoChris · 03-04-2021, 09:14 AM

I have a WZRELB Off Grid 3500w Pure Since Wave 12v DC to 120v AC Solar Power Inverter Home Power Generator.

I'm a little confused...is this unit also a charger without the solar set up? Can it be tied into the RV 120v electrical panel? Do I need additional components to make this work?

astrocamper · 03-04-2021, 10:49 AM

Quote:

Originally Posted by GottagoChris

I have a WZRELB Off Grid 3500w Pure Since Wave 12v DC to 120v AC Solar Power Inverter Home Power Generator.

I'm a little confused...is this unit also a charger without the solar set up? Can it be tied into the RV 120v electrical panel? Do I need additional components to make this work?

The WZRELB is only an inverter.

GottagoChris · 03-04-2021, 11:45 AM

Can I add a separate
charger to complete the system? If so what size? Do you recommend a specific model? Thanx.

astrocamper · 03-04-2021, 12:41 PM

Most RVs come with a converter/charger for taking shore power and creating DC current for house loads an to charge the battery. Make sure it is not connect to the output of your inverter.

People who use inverters usually have some solar panels and solar charge controller to charge the batteries while the sun shines.

I am not sure why the interest in the WZRELB. The "Solar Power" in the name in marketing fluff because there is no MPPT or PWM solar charge controller component that I can see in the specifications.

GottagoChris · 03-04-2021, 10:58 PM

I was under the impression that ALL inverters served both purposes of converting AND charging. I'm learning the hard way. Any recommendations?

astrocamper · 03-05-2021, 07:42 AM

Look at inverter/chargers. Most of them are low frequency with large cores designed to sustain heavy current flows. The less expensive inverters are high frequency versions.

I was happy with my Spartan 2200 watt inverter charger. I only replaced it because I wanted the ability to manage and monitor everything with my Victron Energy Cerbo GX. I now have a Victron Energy Multiplus 3000VA inverter/charger.

The best inverter/chargers can also do load assist. The Victron Energy Multiplus can do this. The Magnum Hybrid inverter/chargers can do this.

Load assist will allow the inverter/charger to monitor the input current to the transfer switch and define a limit on amperage from the input. For example you are plugged into a friends 15 amp circuit while parked in their driveway. You set the input current limit to 12 amps so you don't blow their 15 amp breaker. When your load is below 12 amps in your RV, the extra amperage will go to the battery charger if needed. When the amperage goes above 12 amps, your inverter will synchronize the inverter output and add additional amperage as required to meet the load as long as there is available battery SOC.

This will also allow you to power a larger air conditioner from a modest size generator such as the Honda EU2200 and not have to worry about additional loads starting up since the inverter/charger can provide the additional current necessary to handle startup surges from the air conditioner.

The Victron Energy Multiplus 3000VA can handle brief startup surges up to 6000 watts.

GottagoChris · 03-06-2021, 05:31 PM

Can anyone explain why a single 300ah battery would have a 200amp BMS built it? Is this a pro or a con? Thanx.

twinboat · 03-06-2021, 07:15 PM

Quote:

Originally Posted by GottagoChris

Can anyone explain why a single 300ah battery would have a 200amp BMS built it? Is this a pro or a con? Thanx.

300 AH or any AH ( amphour ) is a measurement of battery capacity.
You can draw 15 amps for 20 hours. 15 x 20 = 300 AHs.

200 hundred amps, or any amps, is the about of amps drawn at any time.
So if you draw more then 200 instant amps, the BMS shuts the battery down.