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Has anyone tried this 12v 3000W LF inverter?

I will post pics and a review on here once I get it. It should arrive tomorrow but wont be until the weekend before I get it wired up. The green plug is for remote start of a genny I think unfortunately my genny doesn't have that feature.
 
Inverter just arrived, it doesn't have the remote socket or the remote start plug. I'm away to contact the seller as it states in the description it should have the remote start
 
Andy, Pike:
Interesting info in this thread. Any updates on this low-budget frequency inverter? I'm in the US, but similar ones seem to be made for 12V--> 110VAC, 60Hz. Since the link supplied in the (amazon.UK) ad doesn't appear to match this product (e.g the manual describes an MPPT solar charge controller,the actual item doesn't seem to have this, etc) any information you can provide would be helpful.

I don't need the bells and whistles (generator start, remote data panel or operation, etc). I don't even >really< need an AC --> battery charger. receptacles, or USB charging ports to be built in. But a robust LF inverter in this capacity and price range would be welcome.

PS: I hope the electricity situation this this winter isn't going to be as rough as it now looks.

Mark, Dayton, OH, USA
 
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Andy, Pike:
Interesting info in this thread. Any updates on this low-budget frequency inverter? I'm in the US, but similar ones seem to be made for 12V--> 110VAC, 60Hz. Since the link supplied in the (amazon.UK) ad doesn't appear to match this product (e.g the manual describes an MPPT solar charge controller,the actual item doesn't seem to have this, etc) any information you can provide would be helpful.

I don't need the bells and whistles (generator start, remote data panel or operation, etc). I don't even >really< need an AC --> battery charger. receptacles, or USB charging ports to be built in. But a robust LF inverter in this capacity and price range would be welcome.

PS: I hope the electricity situation this this winter isn't going to be as rough as it now looks.

Mark, Dayton, OH, USA
There are a range of inverter chargers. So the features vary between the models. I can tell you that the one I purchased from Amazon UK didn't have the remote switch plug but I just extended the On/Off button mounted on the case to a generic inverter switch I purchased off ebay. The generator start wasn't included either.
Those items were excluded due to the chip shortage globally (especially in China)
I did speak to the manufacturing company after LOADs of digging around online.
All these LF inverter units sold under different brand names use the same main components and they just change the metal box slightly.
The inverter works fine. Unless your powering large pumps that have a massive surge, I can't imagine needing more than a 3000w version but they do build much large units.
I've run a 240v chop saw with a 12 inch blade without any problem. I did measure the surge of the chop saw and it was way over 3000w. Sorry can't remember what it was. I've tried (and fried) HF inverters trying to run that chop saw.
No problem running a microwave and a induction hob at the same time but you need the battery and cables and BMS to match you power requirements..
I've got two 300Ah Lifepo4 batteries, both batteries have a 200A BMS.
The cables from the batteries to the inverter are less than 2ft long. Shorter the better.

A 12v to 110v inverter won't be working as hard as my 12v to 240v inverter. (at 3000w you really are pushing the limit of a 12v to 240v system). Any more than 3000w and you need to be running 24v or 48v.
The one modification that you want to make is replacing the cooling fan.
The original fan supplied is really noisy and it kicks in every time the inverter turns on for a couple of seconds.
It's a simple and cheap mod to swap out the standard fan for a quiet one. (the large PC fan is a standard size so it's a straight swap)

Another thing to note is that the 3000w version has a better quality windings than the 1000w & 2000w versions.
From the limited info I found at the time, it seemed the 3000w version used no more power on stand-bye than the smaller versions. Possibly using less power.
When it comes to buying inverters it's always better to buy one bigger than you need. It wont work as hard and will last longer. Plus you have a buffer if and when you require extra power.
I think the biggest mistake most people make is buying an inverter and then you want to power more items. Then your buying twice because your upgrading to a new larger inverter.
The charger is a handy function. Try looking at prices for a 75A charger. The price of a charger that size is almost the cost of this inverter charger.
If i remember correctly people have mentioned some of the other brand names these units and similar larger units are sold under.
They only break if you seriously abuse them and a search online will find the same generic LF complete internals at $120-$150.

So no complaints apart from the excluded function of the remote switch and generator start. (no idea if they have started including them now)
People that purchased this 3000w version a month before me had those functions included but in the UK people don't really use generators and they are not allowed on UK campsites.
P.s there wasn't an MPPT function listed on my unit. Your 110v USA version might have one.
Double check with the supplier, which functions are included before you make the purchase and make sure it has the setting to charge Lifepo4 cells (if that what your charging?)
 
Andy, thanks very much for the report. That, plus your previous information from (extensive) inquiries to the manufacturer, is very useful to me
The inverter works fine. Unless your powering large pumps that have a massive surge, I can't imagine needing more than a 3000w version but they do build much large units.
I've run a 240v chop saw with a 12 inch blade without any problem. I did measure the surge of the chop saw and it was way over 3000w. Sorry can't remember what it was. I've tried (and fried) HF inverters trying to run that chop saw.
I'm seeking to run a submerged well pump. Its not a huge one (1/2 hp, a "two wire" 115 VAC unit that draws about 8 amps when running (so about 920 watts)). The challenge, of course, is the starting surge, which looks to be about 6000 watts. That's why I'm looking for a LF inverter. I don't need to run the pump for long (30 minutes every couple of days), but I do need to run it, and some other things.
The one modification that you want to make is replacing the cooling fan.
The original fan supplied is really noisy and it kicks in every time the inverter turns on for a couple of seconds.
It's a simple and cheap mod to swap out the standard fan for a quiet one. (the large PC fan is a standard size so it's a straight swap)
Thanks, that sounds easy and cheap insurance.
I think the biggest mistake most people make is buying an inverter and then you want to power more items. Then your buying twice because your upgrading to a new larger inverter.
The charger is a handy function. Try looking at prices for a 75A charger. The price of a charger that size is almost the cost of this inverter charger

I'm pretty sure I won't outgrow a 3000W inverter (everyone says that!). This is for a residential backup system,and I'm trying to stick to just "critical needs," no luxuries.
I hadn't strongly considered the possible utility of a big 75A charger. But, since my project is a backup system and my solar panels aren't up until I need them, the ability to use (possibly intermittent) grid power to rapidly bring my batteries back to full charge might be handy.
P.s there wasn't an MPPT function listed on my unit. Your 110v USA version might have one.
The US Amazon listing didn't mention that the unit had an MPPT solar charge controller, but an owner's manual linked from that listing did mention that the unit had an MPPT charge controller. Probably a different model, etc.
Double check with the supplier, which functions are included before you make the purchase and make sure it has the setting to charge Lifepo4 cells (if that what your charging?)
I'm just using flooded lead acid batteries now. Maybe someday . . .

Thanks again for the report. It is good to get firsthand feedback. I'm not ready to buy yet, but having a trusted favorable review of an LF inverter within my budget is very nice. Maybe I'll come across a used "premium" LF inverter (from an EMS or ambulance, etc), but I'm not holding my breath.

Mark
 
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Andy, thanks very much for the report. That, plus your previous information from (extensive) inquiries to the manufacturer, is very useful to me

I'm seeking to run a submerged well pump. Its not a huge one (1/2 hp, a "two wire" 115 VAC unit that draws about 8 amps when running (so about 920 watts)). The challenge, of course, is the starting surge, which looks to be about 6000 watts. That's why I'm looking for a LF inverter. I don't need to run the pump for long (30 minutes every couple of days), but I do need to run it, and some other things.

Thanks, that sounds easy and cheap insurance.


I'm pretty sure I won't outgrow a 3000W inverter (everyone says that!). This is for a residential backup system,and I'm trying to stick to just "critical needs," no luxuries.
I hadn't strongly considered the possible utility of a big 75A charger. But, since my project is a backup system and my solar panels aren't up until I need them, the ability to use (possibly intermittent) grid power to rapidly bring my batteries back to full charge might be handy.

The US Amazon listing didn't mention that the unit had an MPPT solar charge controller, but an owner's manual linked from that listing did mention that the unit had an MPPT charge controller. Probably a different model, etc.

I'm just using flooded lead acid batteries now. Maybe someday . . .

Thanks again for the report. It is good to get firsthand feedback. I'm not ready to buy yet, but having a trusted favorable review of an LF inverter within my budget is very nice. Maybe I'll come across a used "premium" LF inverter (from an EMS or ambulance, etc), but I'm not holding my breath.

Mark
Have you considered looking at building an air lift pump. The cost would be tiny. You would need to pump into a storage tank. It works on the basis that you pump a constant supply of water in small volume into a header tank. A small solar panel and a 12v aquarium air pump are the basic parts. You can lift water from very deep wells. The air is pumped just below the surface of the water and the air bubbles trap water as the bubbles rise up a small diameter pipe. If you pump 2-4 gallons of water per hour for 8 hours per day, that's more than enough water for a family and livestock. If you require more water you can scale up the size of the 12v aquarium air pump, or add a second one. Once you tank is full a switch turns off the pump. You don't even need a battery. I know an on demand water pump is nice but the whole system gets expensive. A raised header tank will give you plenty of water pressure. Loads of info online about air lift pumps. The bonus is there are no mechanical parts to break or wear out. Just a 12v aquarium air pump and they run for years if you put a basic filter on the air intake. No expensive large diameter pipe to buy. You always have the option to pump from the water tank up the the house but that requires less power and a smaller pump, than lifting ground water hundreds of foot to the surface.
 
Have you considered looking at building an air lift pump. The cost would be tiny. You would need to pump into a storage tank. It works on the basis that you pump a constant supply of water in small volume into a header tank. A small solar panel and a 12v aquarium air pump are the basic parts. You can lift water from very deep wells. The air is pumped just below the surface of the water and the air bubbles trap water as the bubbles rise up a small diameter pipe. If you pump 2-4 gallons of water per hour for 8 hours per day, that's more than enough water for a family and livestock. If you require more water you can scale up the size of the 12v aquarium air pump, or add a second one. Once you tank is full a switch turns off the pump. You don't even need a battery. I know an on demand water pump is nice but the whole system gets expensive. A raised header tank will give you plenty of water pressure. Loads of info online about air lift pumps. The bonus is there are no mechanical parts to break or wear out. Just a 12v aquarium air pump and they run for years if you put a basic filter on the air intake. No expensive large diameter pipe to buy. You always have the option to pump from the water tank up the the house but that requires less power and a smaller pump, than lifting ground water hundreds of foot to the surface.
Andy, thanks. I did look into this, it's not a widely known approach to lifting water, I'm surprised you came across it.
As I understand things (and I may >very< well be wrong), it's not the action of the rising bubbles that does the work. Instead, by adding bubbles to a column of water we are decreasing the density of that column (the air bubbles are a lot less dense than the water they displace, so the column as a whole is considerably less dense than an equivalent column of pure water. The bubbly column is buoyed up surrounding column of "pure" water ).
A simple example: If we imagine my 5" diameter steel well bore that goes down 150' below grade. The static water level is at, say, 40' below grade. I put a 1" diameter PVC pipe down 120' below grade (so the top 40' is filled with air, the bottom 80' is filled with water). Now, I bubble in air at the bottom of that PVC pipe, and as the bubbles rise they eventually reach to the top. For simplicity, let's say the resulting column of water in the PVC pipe has 1/2 the density of the "unbubbled" water in my well. So, it has buoyancy (just as if it were made of styrofoam, etc of similar density) and this less dense bouyant column is lifted up by the more dense "pure" water surrounding it in my well casing. It gets lifted, and the top of the column is now above the static water level in my well. A few observations:
1) The air from my pump must enter way down in the PVC column so it can fill it with air bubbles. The air bubbles won't come out of my bubbler unless the air pressure exceeds the water pressure at that depth. In our example above, our 80 ft of water above the air bubbler exerts a hydrostatic pressure of 35psi (238 kPa), so my air compressor needs to pump air against that pressure to get the first bubble out.

2) Since the bubbles do rise through the column and exit at the top, I need to continually add air to the column just to keep its density at the same low amount so that the column remains buoyant. I don't recall the formula for this air volume, but it isn't trivial. Working from memory, I think I figured out I'd need about a 1/2 hp compressor to produce the needed air volume (in CFM) against that 35PSI backpressure and get a fairly small flow of water at the top. That's about the same power requirement as my existing conventional well pump.

3) My well is deep enough, but some aren't. Again, working from memory, I believe the general rule is something like: "you need 2 feet of bubbly column below the static water line for every foot of lift you want."

Anyway, you jogged my memory and I'll look for my notes again sometime. The approach is pretty popular among folks doing hydroponics because their lifts are small (so, little back pressure at the compressor) and very filthy water can be pumped this way. If you need to aerate the water anyway to keep the pond/crops health, then this amounts to a "free" way to lift water. For my use it might not be perfect. It does have the (significant) advantage that all the mechanical stuff is outside the well and easily serviced.

I've also considered:

- Replacing my "everyday" 115VAC 1/2 hp electric pump (they cost about $250, last about 15 years) with a Grundfos 1/2 HP DC pump (about $900 to replace). Advantage--no-fuss transition to "solar" pumping of residential water if the AC power becomes unavailable.
- Hand pumps (not fun, but apparently pretty bulletproof as long as the water level in my well doesn't go down too far during a dry period). As you suggested, I'd pump the water into a tank and move it wherever I want (even pressurize the house plumbing) with a simple 12VDC diaphragm pump as used by RVs (caravans), etc
- When the AC goes out, snake a small diameter (approx 1.8") 12VDC deep well pump into my well in addition to the existing pipe and wires from the existing pump. A pump like this one (approx $200): https://www.ierents.com/product-p/prop-10300.htm
165 watts, it provides about 1.2 GPM at a lift of 40 feet (above the static height of the water, not the depth of the pump). At that wattage, in good sun I could run it continually during the daylight hours on two 100W panels (so, about 360 gallons over 5 hours, MUCH more than I need). Pros: This approach works even if my well pump AND inverter crump out: the pump can be powered directly from my battery (or panels-->SCC in the daytime). Cons: Apparently the pump isn't supposed to sit in water continuously and the motor can only be expected to last 400 hours.

Anyway, I need some sort of inverter anyway for other loads, so going with a "beefy" LF inverter lets me use my existing 115VAC well pump with no new piping, etc. Overall, it's the low-cost option (about $250 more than the 1500w HF inverter I'd otherwise buy). I'll surely also build a hand-pump and get a small12VDC membrane pump (a very handy thing).
Sorry to get off-track from the inverter issue.
 
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