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[MattLeonard]

I often power small sound systems (speakers-on-stick size) with a LiFeP04 batteries/inverter setup - great for off-grid events. Usually, this is a 3kw inverter (so reliably a single 20a circuit). But for some slightly larger events - I'd like to use a 2nd inverter/battery setup that I could use - basically creating a 2nd circuit option.  Ideally - this could mean one inverter per side of PA, or PA on one circuit and monitors/backline on the 2nd.

-What are some considerations/best practices I should be thinking about if using (2) fully independent power sources?

-I know on traditional gennies a bonding kit is the norm - and while I could bond the chassis of multiple inverters together, I don't have the ability to sync phase. What are the real-world implications here?

-Could I physically isolate parts of the system that are on different power sources? i.e. - using wireless transmitter/receivers so that no physical path (copper or human) is possible between components?

I'd much rather than multiple 3kw inverters for modularity/redundancy than a single 6kw unit if possible. Thanks for any advice!





Grounding between them?

[Stephen Swaffer]

I would bond the chassis together.  Basically, code calls for anything that "could be energized" to be bonded to a common ground to avoid "potential" (as in voltage) differences.

Why would syncing phase matter?  Does any of your equipment NOT convert the AC to DC before using it?

[Riley Casey]

Speaking of Lithium battery power inverters what kind of run time are you getting with what kind of audio system? I'e been looking at these for small powered mixer & speaker on stick voice systems.

https://www.amazon.com/gp/product/B07SM5HBK1/ref=ox_sc_act_image_1?smid=AZF6YB7UVA7OU&psc=1

[Steve-White]

I'm thinking about putting together an inverter setup for garden/gazebo weddings instead of the inverter genny.  It's pretty quiet and at 100' away with a large cart tipped on it's side is inaudible.  But, a battery inverter would be faster setup and tear down and that's the name of the game.

Thinking something with quick change out battery packs in case of a problem or long run time is needed.

That Jackery 518WH looks pretty good.  Packaged up, probably want two of them - better solution anyway than a single rig with spare battery packs.  Should have plenty of grunt to run a wedding ceremony size PA for 45 minutes or so, much of which is idle time on the system.

For the OP, heed what Stephen posted about bonding.  Absolutely positively bond multiple portable power sources together well.  That's a huge safety precaution.

[MattLeonard]

I'm thinking about putting together an inverter setup for garden/gazebo weddings instead of the inverter genny.  It's pretty quiet and at 100' away with a large cart tipped on it's side is inaudible.  But, a battery inverter would be faster setup and tear down and that's the name of the game.

Thinking something with quick change out battery packs in case of a problem or long run time is needed.

That Jackery 518WH looks pretty good.  Packaged up, probably want two of them - better solution anyway than a single rig with spare battery packs.  Should have plenty of grunt to run a wedding ceremony size PA for 45 minutes or so, much of which is idle time on the system.

For the OP, heed what Stephen posted about bonding.  Absolutely positively bond multiple portable power sources together well.  That's a huge safety precaution.

 I think the small Jackery-size units are very limiting to what you can run - be cautious of the consumer-level inverter units that may not really be able to output the wattage the claim, at least not reliably, or handle transients in dynamic music.  And that won't deliver their full stated capacity either. Plan for a solid buffer on all specs. It really depends on the program material and volume - most Class D amplifier/powered speakers are very, very efficient and sip power.

The smallest inverter I use is a 1500w unit, and I've comfortably run 3 QSC k10.2's on that - at full (but not clipping/limiting) volume. I have done 4 (not at full volume) but have also had the inverter going into protect on some peaks. I ran a pair of Yamaha DXS subs and DZR tops (with a small mixer and pair of Sennheiser wireless) last night on my 3,000 water inverter - full volume, and it didn't blink.


If you want consumer form factor and ease - look at Bluetti or Delta Pro - both are releasing new units right now that are nextg-gen in terms of features, weight, energy density etc.  And they have expandable battery options - which is clutch
.

For more power at lower cost - DIIYsomething if you have basic electrical comfort. I have a pair of milkcrates that each hold ~2500wh of lithium-ion batteries. With an Anderson SB175 quick-connect cable - I can connect that to any of my inverters (mounted on plywood that sits nicely on top of the crate) and its module and light.  A more "pro looking" option would be to build  into a Pelican or similar)

[Riley Casey]

My question would be how long did you run the systems you described and for what kind of program material? Rock bands vs spoken word are going to be radically different power consumption.  I've also found this unit with socketed battery packs which looks much more applicable to what we do.

https://egopowerplus.com/nexus-portable-power-station/

...
The smallest inverter I use is a 1500w unit, and I've comfortably run 3 QSC k10.2's on that - at full (but not clipping/limiting) volume. I have done 4 (not at full volume) but have also had the inverter going into protect on some peaks. I ran a pair of Yamaha DXS subs and DZR tops (with a small mixer and pair of Sennheiser wireless) last night on my 3,000 water inverter - full volume, and it didn't blink.


If you want consumer form factor and ease - look at Bluetti or Delta Pro - both are releasing new units right now that are nextg-gen in terms of features, weight, energy density etc.  And they have expandable battery options - which is clutch
.

For more power at lower cost - DIIYsomething if you have basic electrical comfort. I have a pair of milkcrates that each hold ~2500wh of lithium-ion batteries. With an Anderson SB175 quick-connect cable - I can connect that to any of my inverters (mounted on plywood that sits nicely on top of the crate) and its module and light.  A more "pro looking" option would be to build  into a Pelican or similar)

[Steve-White]

I think the small Jackery-size units are very limiting to what you can run - be cautious of the consumer-level inverter units that may not really be able to output the wattage the claim, at least not reliably, or handle transients in dynamic music.  And that won't deliver their full stated capacity either. Plan for a solid buffer on all specs. It really depends on the program material and volume - most Class D amplifier/powered speakers are very, very efficient and sip power.

The smallest inverter I use is a 1500w unit, and I've comfortably run 3 QSC k10.2's on that - at full (but not clipping/limiting) volume. I have done 4 (not at full volume) but have also had the inverter going into protect on some peaks. I ran a pair of Yamaha DXS subs and DZR tops (with a small mixer and pair of Sennheiser wireless) last night on my 3,000 water inverter - full volume, and it didn't blink.

If you want consumer form factor and ease - look at Bluetti or Delta Pro - both are releasing new units right now that are nextg-gen in terms of features, weight, energy density etc.  And they have expandable battery options - which is clutch.

For more power at lower cost - DIIYsomething if you have basic electrical comfort. I have a pair of milkcrates that each hold ~2500wh of lithium-ion batteries. With an Anderson SB175 quick-connect cable - I can connect that to any of my inverters (mounted on plywood that sits nicely on top of the crate) and its module and light.  A more "pro looking" option would be to build  into a Pelican or similar)

Exactly for the DIY option.  I looked at the packaged up units again and the first thing that came to mind was putting them into the truck.  They would need to be cased up.  I had a couple of those little generators that are in a nice little rounded form factor with molded in handle.  Gone.  I use all full frame generators now for both fuel capacity and packing with other gear.

Yeah, it will be custom for sure with replaceable battery packs and probably fit into a standard 19" road case for integration both while in use and in the truck.

What inverters are you using?  What batteries?

[MattLeonard]

Exactly for the DIY option.  I looked at the packaged up units again and the first thing that came to mind was putting them into the truck.  They would need to be cased up.  I had a couple of those little generators that are in a nice little rounded form factor with molded in handle.  Gone.  I use all full frame generators now for both fuel capacity and packing with other gear.

Yeah, it will be custom for sure with replaceable battery packs and probably fit into a standard 19" road case for integration both while in use and in the truck.

What inverters are you using?  What batteries?

I have 4 drop-in 12v (well, 14.4v LiFeP04) Lion UT-1300 batteries (2 per milk crate wired in series for a 24v system, along with  MRBF fuses - ~2500wh per crate), and then a few different inverters. While the robustness of a low-frequency inverter (previously had a Victron) are undoubtedly more reliable - I have some cheaper (Giandel) high-frequency units that I have had zero issues with, and they weigh less than half as much. All pure sine wave of course. The battery setup allows me to have (2) different rigs, or parallel the crates together to have longer run-time if needed.

As someone (Riley) above mentioned - power consumption varies dramatically based on the program material. I ran 2x DSX subs and 2x DZR tops (all efficient Class D amps) last night for 3 hours - lower/medium-volume hip-hop for 90 minutes and speech for 90 minutes.  I used just slightly over 1,000wh (I wasn't measuring peaks, unfortunately). A full-volume nonstop DJ would of course use more than a speech-heavy event which has a lot of idle time between content.

As far as rack-mount options - Gyll makes some rack-mount batteries for this purpose. I haven't seen inverters that rack-mount, but it wouldn't be hard to fashion something road-worthy. I just built a small plywood frame for my inverters, and the milk crates are robust enough (and lightweight) for my battery needs.

[Art Welter]

My question would be how long did you run the systems you described and for what kind of program material? Rock bands vs spoken word are going to be radically different power consumption.  I've also found this unit with socketed battery packs which looks much more applicable to what we do.

https://egopowerplus.com/nexus-portable-power-station/

Riley,

Regardless of quiescent vs peak vs long term music/voice average, the amount of power delivered can be measured in watt (or killowatt..) hours, the ability to deliver that power depends on the type and capacity of the storage battery.

The Nexus portable power station uses up to four of the EGO 56V ARC Lithium™ batteries, the largest being the 10Ah, 560 watt hours each, total of 2240 watt hours. For long term lithium battery life, probably don't want to use more than 80% between recharge, so figure around 1792 watt hours.

Matt Leonard's pair of ~2500 watt hour batteries total 5000 watt hours, 80% around 4000 watt hours, over double the run time, whatever is being run  .

Art

[Steve-White]

I can customize the rack mount in my shop.  It'll be a decision of battery and inverter in a case together with quick swap capability for the battery pack or separate battery packs in their own cases which will probably be the simplest way to go.  24V setup looks pretty good with 12V batteries in series.

[ProSoundWeb Community]