cheap Mppt any good ?

[Ellcon123]

Just an update. My 2 Ecgsolax units have performed flawlessly. Maxing out at about 900W indicated. Test will be as the days lengthen when it should reach 1200W. They do run hot so have added external fan.

I couldn't figure out if they have uart so data logging is through hall sensor on output.

 

[fafrd]

Just an update. My 2 Ecgsolax units have performed flawlessly. Maxing out at about 900W indicated. Test will be as the days lengthen when it should reach 1200W. They do run hot so have added external fan.

I couldn't figure out if they have uart so data logging is through hall sensor on output.

Uhhh, longest day of the year was 6 days ago (June 21st).

Days are already shortening…

The length of the day has everything to do with energy output (kWh) but less to do with peak output power (W) than angle of the sun and other factors like ambient temperature.

If you have never explored PV Watts, it will model hourly power output of your array through the year. Most use it to estimate energy production but it can also be used to determine peak solar power input to your array:

PVWatts

Estimates the energy production and cost of energy of grid-connected photovoltaic (PV) energy systems throughout the world. It allows homeowners, small building owners, installers and manufacturers to easily develop estimates of the performance of potential PV installations

pvwatts.nrel.gov

 

[Samsonite801]

Uhhh, longest day of the year was 6 days ago (June 21st).

Days are already shortening…

The length of the day has everything to do with energy output (kWh) but less to do with peak output power (W) than angle of the sun and other factors like ambient temperature.

If you have never explored PV Watts, it will model hourly power output of your array through the year. Most use it to estimate energy production but it can also be used to determine peak solar power input to your array:

PVWatts

Estimates the energy production and cost of energy of grid-connected photovoltaic (PV) energy systems throughout the world. It allows homeowners, small building owners, installers and manufacturers to easily develop estimates of the performance of potential PV installations

pvwatts.nrel.gov

He might be in Australia (Southern Hemisphere). I see another post of his possibly indicating such.

 

[Ellcon123]

There is another half to the globe

 

[Samsonite801]

There is another half to the globe

Haha yeah I figured as much, I seen this post and saw a subtle clue:

Sol-Ark 15K Rejected by PG&E in California

Just completed 2 Grid tied installs in California in the PG&E utility area with the Sol-Ark 15k.... and PG&E denied us (Please see the attached for their response). I have contacted Sol-Ark and they are aware of the issues, but other than acknowledging that there is an issue I have net received...

diysolarforum.com

 

[Ellcon123]

Length of the day and angle of the Sun are related. Middle of summer and the Sun will be a bit to high. Add for heat and peak power will be affected. Don't need PVwatts to tell me my production I have the data.

Winter production is not to bad considering the hours and shading. We've just come out of 3 years of high rainfall so things are looking up.

 

[fafrd]

Length of the day and angle of the Sun are related. Middle of summer and the Sun will be a bit to high. Add for heat and peak power will be affected. Don't need PVwatts to tell me my production I have the data.

Winter production is not to bad considering the hours and shading. We've just come out of 3 years of high rainfall so things are looking up.

OK, so when your lead post referred to ‘as the days lengthen’ what you meant was ‘as the mid-day angle of the sun begins to drop’ - that makes total sense.

 

[Skypower]

I’ve installed a few Victron solar charge controllers on sailboats. They are cheap if you figure how hard they work for you vs ?????. I like them because the start working earlier and make the most out of what they get. Cheap is a relative term. If you buy cheap, you usually get less later.

 

[Ellcon123]

OK, so when your lead post referred to ‘as the days lengthen’ what you meant was ‘as the mid-day angle of the sun begins to drop’ - that makes total sense.

At my latitude and the angle of my panels the summer sun has gone past being perpendicular to the panels at mid day. It's to high in the sky.

Winter wouldn't be that bad but lower panels are shaded most of the day. Biggest killer to power appears to be heat so spring and autumn should be as good as summer.

 

[fafrd]

At my latitude and the angle of my panels the summer sun has gone past being perpendicular to the panels at mid day. It's to high in the sky.

Winter wouldn't be that bad but lower panels are shaded most of the day. Biggest killer to power appears to be heat so spring and autumn should be as good as summer.

Makes total sense (and that’s the reason I referred to the importance of sun angle to peak output power in my initial post).

So you’re arrays are positioned to optimize output for sun angle in spring / fall and you lose some potential power you could have generated with a flatter angle during summer months when the sun is high overhead.

That’s a nice way to spread out your generation so you get more in fall, winter, and summer when you need it at the cost of a bit of lost generation in summer when you don’t.

It was just your initial reference to ‘as the days lengthen’ that confused me since days are already shortening and what you really means was ‘as the midday sun starts dipping lower.’

The angle of my array is fixed by my roof, otherwise I’d increase tilt to trade off some summer production for increased fall, winter, and spring production like you have…

 

[Ellcon123]

I'm in the southern hemisphere so days are lengthening. Mine are also mounted on the roof so angle is fixed. The north roof face is max'd for panels so I have a few others in various locationa that at least generate something. Using 3 charge controllers and a micro inverter but most of the power is through the cheap Ecgsolax units. Haven't bothered checking efficiency, it is what it is. Just measure the power going to batteries.

 

[fafrd]

I'm in the southern hemisphere so days are lengthening.

Ahhh, that explains it then - you just passed your darkest day of winter .

Mine are also mounted on the roof so angle is fixed. The north roof face is max'd for panels so I have a few others in various locationa that at least generate something. Using 3 charge controllers and a micro inverter but most of the power is through the cheap Ecgsolax units. Haven't bothered checking efficiency, it is what it is. Just measure the power going to batteries.

I’ve got mostly grid-tied Microinverters on my SW-facing roof (San Francisco Bay Area) but have 3 DC-coupled 380W panels on a SE-facing roof to get a bit more early-morning power.

I’m using an Epever 60A SCC which I’ve been very happy with - not sure how the price of those compares to your Ecgsolax SCC…

What other SCCs are you using?

And how does a Microinverter figure into things - do you have an export agreement or just maintain sufficient daytime load to absorb everything before it reaches the grid?

 

[Ellcon123]

I started playing with solar in 2020 and bought 8 x 120Ah cells. I was using a few '18V' panels and bought MSB's as they were cheap. I used a cheap HF inverter but also added an LF type from China. I used this setup for powering some spare fridges and doing my yard work.

I added an extra battery of 200Ah cells in 2021. Another 200Ah pack was bought in 2022 along with a 3kW LF inverter. The 3rd battery was not installed until early this year as I had to make a larger solar cupboard in a better location. In early 2022 I picked up 20 x 200W panels cheap but it's only the last 4 months that I'm really getting my system running properly.

I managed to kill 3 x 60A MSB's in quick succession through my own siliness. Production was thus poor and I happened across the Ecgsolax for $65ea on Aliexpress! Price was real and they arrived within 2 weeks. They are working great and I'm a bit more careful on what breakers I switch.

I have 2 panels on my chook shed and thought a microinverter would be good as I can run 240V through thinner wires. So I have a 300W microinverter backfeeding through the LF inverter. The panels only produce for around 3 hours but it gives me another kW. This runs through a smart plug so I can collect data through Home Assistant.

My system is off-grid so this powers spare fridges, washing machine, and clothes dryer. We had a long wet spell, 2020 to early 2023, so it's been very helpful with the washing!

 

[BuffaloTrace]

Current recap on cheap Mppt any good? Posted here:

cheap Mppt any good ?

Everybody has an opinion on that. If you dismiss the confirmation bias and ‘gee, I made such an excellent choice’ kind of low-knuckled reviews on cheap stuff you can discern stuff. Mskeskybrew reportedly isn’t consistent parts, but some people think they’re the best. The powerMR by (apparent?)...

diysolarforum.com

Any more compareable units to add? The consensus on these "MSB" style units seems to be the leader for the topic.

 

[lightbulb]

I’ve installed a few Victron solar charge controllers on sailboats. They are cheap if you figure how hard they work for you vs ?????. I like them because the start working earlier and make the most out of what they get. Cheap is a relative term. If you buy cheap, you usually get less later.

I have been using Epever for 3 years. I have bought 8 in that time. They work. I have 5 in service now. I bought an Aims that was not configurable enough for me. Just picked up a Victron AC to DC charger. My next SCC will probably be Victron.

 

[fafrd]

I started playing with solar in 2020 and bought 8 x 120Ah cells. I was using a few '18V' panels and bought MSB's as they were cheap. I used a cheap HF inverter but also added an LF type from China. I used this setup for powering some spare fridges and doing my yard work.

I added an extra battery of 200Ah cells in 2021. Another 200Ah pack was bought in 2022 along with a 3kW LF inverter. The 3rd battery was not installed until early this year as I had to make a larger solar cupboard in a better location. In early 2022 I picked up 20 x 200W panels cheap but it's only the last 4 months that I'm really getting my system running properly.

I managed to kill 3 x 60A MSB's in quick succession through my own siliness. Production was thus poor and I happened across the Ecgsolax for $65ea on Aliexpress! Price was real and they arrived within 2 weeks. They are working great and I'm a bit more careful on what breakers I switch.

If what you bought was one of these: https://m.aliexpress.us/item/325680....1005005504967791&gatewayAdapt=gloPc2usaMsite that’s the unit most call ‘PowerMr’ (though I don’t know who the manufacturer is). You can find several threads of other members using PowerMr SCCs here on the forum..

Some of those threads include failures, warnings, and fixes, so could be worth the effort to check them out.

Price for 60A is hard to beat, that’s for sure…

I have 2 panels on my chook shed and thought a microinverter would be good as I can run 240V through thinner wires. So I have a 300W microinverter backfeeding through the LF inverter. The panels only produce for around 3 hours but it gives me another kW. This runs through a smart plug so I can collect data through Home Assistant.

My system is off-grid so this powers spare fridges, washing machine, and clothes dryer. We had a long wet spell, 2020 to early 2023, so it's been very helpful with the washing!

So your Microinverter is boosting the power available from your LF inverter by as much as 300W (off-grid).

As long as you always have load exceeding Microinverter output, I see how that will work, but what happens if the load drops below what the Microinverter is putting out?

 

[Ellcon123]

It's that unit but the board in the Ecgsolax is different from any I have seen for PowerMr or MSB. No markings or any dates on it. I steered clear of PowerMr as I read of to many issues. These Ecgsolax are running faultlessly. Haven't had to reboot since I started using them. Will see if that continues into summer with higher wattage from the panels.

As for the microinverter, system load doesn't matter. It's either offsetting load or backfeeding to the batteries. In Home Assistant I have the smart plug turned off overnight. To mimic an SCC I also have it set to turn off and on at the same battery voltages to the SCC's.

 

[fafrd]

It's that unit but the board in the Ecgsolax is different from any I have seen for PowerMr or MSB. No markings or any dates on it. I steered clear of PowerMr as I read of to many issues. These Ecgsolax are running faultlessly. Haven't had to reboot since I started using them. Will see if that continues into summer with higher wattage from the panels.

Hmmm, will have to check them out…

As for the microinverter, system load doesn't matter. It's either offsetting load or backfeeding to the batteries. In Home Assistant I have the smart plug turned off overnight. To mimic an SCC I also have it set to turn off and on at the same battery voltages to the SCC's.

So your LF inverter will absorb any excess Microinverter power by using it to charge the battery? Nice.

Sounds like it is never an issue but what happens if the battery is full and the LF battery charger cannot absorb all of the excess AC energy being generated by the Microinverter?

 

[Ellcon123]

The microinverter is plugged into a smart plug on a power strip which is the output from the LF inverter. LF inverters can run in both directions. The microinverter syncs to the LF ac and generates power. If the battery is 28V then Home Assistant turns the smart plug off so the microinverter shuts down.

The black/red extension lead comes from the microinverter. White plug is power strip and the orange lead runs to my laundry. Orange/black extension lead runs to the garage fridge.

 

[BuffaloTrace]

I dig your mounting idea of the charge controllers on those boltless shelving legs. The aluminum bars is a nice touch too.