24v Inverter Recommendation

[alferz]

I'm searching for an inverter that increasingly seems like a unicorn. After trialing a few I just cant seem to find the one. Anyone have any recommendation on an inverter that would meet these specs?

- 24v/2000-3000w
- NO low frequency transformer hum (its going in an occupied space)
- Hard wired AC Output (not tacked on to some cheap terminals on the exterior of the unit like a WZRELB, but in some kind of enclosure)
- Thermally controlled fans, based on actual temperature vs just amperage
- Low idle current, like 15W or less (will be on 24/7)
- Nice to Have: Built-in AC Charging @ 50a+

Ruled out:
- Multiplus-II (the hum on this thing is obnoxious)
- Sungold 3000w (37w idle draw, fans linked to amps vs temps)
- Pretty much every cheap Amazon inverter I've tried (idle current too high, crappy hardwire connections)

 

[time2roll]

Morningstar has a new line of inverters out recently.

https://www.morningstarcorp.com/wp-content/uploads/datasheet-suresine-2-en.pdf

https://www.morningstarcorp.com/new-products-fall-2022/

I expect these to do well as their solar products have been great. The large one is 48v

Another try would be GoPower 3000-24

I have the older 2000-12 and it works great for my needs.

https://www.amazon.com/Go-Power-GP-ISW3000-24-Certified-Inverter/dp/B01NCQ9TIT

https://s3-us-west-2.amazonaws.com/catsy.549/SPEC_GP-ISW2000_3000_RevE-min.pdf

 

[AustinMTB]

- 24v/2000-3000w
- NO low frequency transformer hum (its going in an occupied space)
- Hard wired AC Output (not tacked on to some cheap terminals on the exterior of the unit like a WZRELB, but in some kind of enclosure)
- Thermally controlled fans, based on actual temperature vs just amperage
- Low idle current, like 15W or less (will be on 24/7)
- Nice to Have: Built-in AC Charging @ 50a+

For my off-grid shed I was looking for a similarly-sized system. I decided on the MPP PIP2024 LV-MK.

It meets most of what you're looking for and can support up to 60A utility charging, but it's idle power consumption is spec'd as "<30W". I've measured mine at 27W FWIW.

The other con is the fan. When idle, the fans are run at a low rate and are silent, but as soon as I turned on a 1200W space heater for a test, the fans immediately kicked into high speed and were noisy. Not nearly as loud as a hair dryer on high, but louder than a hair dryer on low.

BTW, that heater took 1280W and the unit reported 64% of load capacity, and pulled 53A from the battery. 53A * 26.6V = 1410W. 1280/1410 is about 90% which matches the spec'd efficiency of this inverter.

I found it very hard to locate details like "fan noise" (or fan behavior like you mention), and I can't tell you how many manuals I've downloaded for 24 and 48 V units. Other units have a surprisingly low eco/idle mode, as low as 7W on some. The 2024 has something they call an eco mode but I don't know what it does yet.

I received this unit the other day and have had the battery and panels connected for charging, but I've only been using the inverter for testing today, so I don't have enough experience with it to give any more details about it day-to-day.

 

[alferz]

@AustinMTB I hear you on the manuals, I feel like I have read at least 40 in the past month. I wish noise level was a spec on the datasheet for these units. There are many use cases where the unit will be in earshot of, maybe even directly in, a living area. The environmental specs should include a DBA level, both at idle and at various watt load levels. One can only hope.

In my case I think I have decided to keep the Multiplus-II. This thing is a real tank. The specs, software, and build quality are perfect as an off-grid/critical loads sort of UPS system where select circuits can be backed up. The only problem with it is the noise level, the huge toroidal transformer (see pic) in this thing gives off a very official sounding hum even at zero load. The transformer sounds like a spaceship when its getting up to 70a charging. The fans get pretty loud also, but luckily they are temp based, not based on current draw so they dont even come on at low loads. I dont think I could live with it in my off-grid shed/office, and in a sleeping space would be unacceptable too, due to that hum. But in a garage, utility room, attic etc noise is less a problem. The best part is 11 watts self consumption. This current is always flowing at zero watts or 1000 watts and acts as an always on tax on your battery bank. If you’re trying to maximize off grid capacity, I would say the self consumption is the most important spec of all. Given the choices I am pretty impressed with this unit.

 

[alferz]

Wanted to add RE eco mode: Victron calls it AES or search mode. The way I understand it, is that below a certain threshhold, configurable on some units but defaulting to about 50w on most of the ones I’ve seen, the inverter goes into a low power mode that “searches“ for current demand every .5 or 1 seconds by applying voltage to the line and measuring if a current draw is there. If it finds the demand over the watt threshhold, it turns on the full inverter and serves the load, otherwise goes back into sleep mode for .5 or 1 second and does the search again. This may be fine for a lot of situations, for me I have low current devices (network devices, raspberry pi, cable box, etc) that need power 24x7 so the key number in my situation is the full on self consumption numbers. The “full on” self consumption adds onto whatever load you are drawing, so for the MP a 10 watt 24x7 device would draw a total of 21 watts from the battery. As the battery gets larger this becomes less and less an issue, but you have to factor in that number with sizing the solar array. For instance, with 30w you would have 720wh per day to account for and need to be replaced by solar without taking into account the actual loads. If you can shut the inverter off when not used this is much less an issue so it just depends on the use case.

 

[AustinMTB]

I looked into the eco mode on the MPP 2024, and it doesn't appear to operate like the other eco modes you describe. On this unit, it is indistinguishable from bypass mode, but the who knows because the manual doesn't define it nor is there a power consumption rating for eco mode.

Yeah, the 27W inverter base load is just another load I included in my power estimates. It's a waste, but accounted for at least.

 

[Symbioquine]

In my case I think I have decided to keep the Multiplus-II.

Probably a good call. I'd guess you'll be hard-pressed to find a better inverter overall. Can you just change the location/mounting/enclosure for the inverter such that the hum isn't such an issue?

I have my Multiplus' (older version, not "Multiplus-II") in an outdoor cabinet and the hum is pretty minimal from a few feet away and barely noticible with the cabinet closed.

 

[Diemjoe]

I'm searching for an inverter that increasingly seems like a unicorn. After trialing a few I just cant seem to find the one. Anyone have any recommendation on an inverter that would meet these specs?

- 24v/2000-3000w
- NO low frequency transformer hum (its going in an occupied space)
- Hard wired AC Output (not tacked on to some cheap terminals on the exterior of the unit like a WZRELB, but in some kind of enclosure)
- Thermally controlled fans, based on actual temperature vs just amperage
- Low idle current, like 15W or less (will be on 24/7)
- Nice to Have: Built-in AC Charging @ 50a+

Ruled out:
- Multiplus-II (the hum on this thing is obnoxious)
- Sungold 3000w (37w idle draw, fans linked to amps vs temps)
- Pretty much every cheap Amazon inverter I've tried (idle current too high, crappy hardwire connections)

I bought an MPP lv2424 and a couple big Battery 12v Lithiums. So far I am regretting it. The big batteries don't support 12v series set up so using some old deepcycle lead acid. The lv2424 turns off when voltage falls below 23v which is probably good for lead acid but a problem for Lithium. I would love for it to stretch further so I don't have to fire up the generator to get them charged especially since Lithiums can handle lower voltage levels. Makes me think separate mppt and inverter might have been a better idea.

 

[Symbioquine]

The lv2424 turns off when voltage falls below 23v which is probably good for lead acid but a problem for Lithium [...] especially since Lithiums can handle lower voltage levels

It's probably not great for longevity to discharge them below ~2.9v per cell (23.2v for an 8S battery) if they're LiFePO4 cells regardless of what the datasheet says.

 

[Brett V]

Cotek SP3000-124 - Inverter Supply

Shop for Cotek SP3000-124 at Inverter Supply for best prices online. Cotek SP3000-124, Cotek, SP3000-124, 3000W 24VDC 110/115/120 UL Hardwire Pure Sine Wave Inverter, Cotek SP Series Inverters

www.invertersupply.com

Cotek makes decent stuff. They have units with built in charging as well but I have no experience with those.

 

[Diemjoe]

Cotek SP3000-124 - Inverter Supply

Shop for Cotek SP3000-124 at Inverter Supply for best prices online. Cotek SP3000-124, Cotek, SP3000-124, 3000W 24VDC 110/115/120 UL Hardwire Pure Sine Wave Inverter, Cotek SP Series Inverters

www.invertersupply.com

Cotek makes decent stuff. They have units with built in charging as well but I have no experience with those.

Thanks. Am in a quandary about what to do. I have $2k in parallel only batteries and $800 on the hybrid charger/inverter. I think I can find other uses for the batteries and the hybrid charger would be nice for the cabin and I can double it up for a 220Ac to power the well pump.

 

[vbadov]

@AustinMTB I hear you on the manuals, I feel like I have read at least 40 in the past month. I wish noise level was a spec on the datasheet for these units. There are many use cases where the unit will be in earshot of, maybe even directly in, a living area. The environmental specs should include a DBA level, both at idle and at various watt load levels. One can only hope.

In my case I think I have decided to keep the Multiplus-II. This thing is a real tank. The specs, software, and build quality are perfect as an off-grid/critical loads sort of UPS system where select circuits can be backed up. The only problem with it is the noise level, the huge toroidal transformer (see pic) in this thing gives off a very official sounding hum even at zero load. The transformer sounds like a spaceship when its getting up to 70a charging. The fans get pretty loud also, but luckily they are temp based, not based on current draw so they dont even come on at low loads. I dont think I could live with it in my off-grid shed/office, and in a sleeping space would be unacceptable too, due to that hum. But in a garage, utility room, attic etc noise is less a problem. The best part is 11 watts self consumption. This current is always flowing at zero watts or 1000 watts and acts as an always on tax on your battery bank. If you’re trying to maximize off grid capacity, I would say the self consumption is the most important spec of all. Given the choices I am pretty impressed with this unit.

Very interesting I want to thank everybody for the conversation and information

 

[pollenface]

I like Cnswipower. They have good reviews. Can only seem to buy them through their ebay store but shipping was surprisingly fast when i bought mine, i got it in less than a week from China.

 

[hbl]

I know this thread is a bit old, but Im also looking for at 24v HF inverter around 2000-3000w.

What about the Ective Inverter, like the TSI model with switch over capability. Been looking at it myself, but cant find any review.
Spec look good and low idle consumption.

https://www.ective.de/ECTIVE-TSI-25-Sinus-Inverter-24V
Use google translate as its in German.