Cannot understand this Chinese solar charge controller
- Thread starter corporal_Canada
- Start date
corporal_Canada
New Member
As for audit.. like I've mentioned earlier, I'll be happy if this entire setup lets me use my PC and monitor for 6 to 24 hours, but that seems like a fantasy now, I was hoping my tiny refrigerator (440 watts)....
So since I can't function a average low end PC and monitor... I won't invest any further,..... And alligator things I just call clamps... Are now connected using ring terminals.... Slightly cleaner...
And forgot to mention.. the big black thing is the battery, barely 6 months old, so not that used as you might imagine
This is what I meant by throwing money at things before actually knowing what your actual needs are..
Which is what so many do...
And then all too many complain when they don't get the results they imagined they would..
People who know what they are doing (ie those who have studied the field extensively, or are in the actual business) will do things correctly, and can put together a system that actually works...
And knowing what your energy requirements actually are is the vital first step- then sizing the equipment needed, the panels size/number/wattage required for a specific location for the usage needed...
Your fridge is another thing that seems to be using absurdly high power- especially for a 'tiny fridge'- 440watts is literally 4-5 times the power of a modern family HOUSEHOLD fridge...
Mine here is a household fridge- over 20 years old- and the running current is 150w (I disconnected its defroster several years ago when it failed S/C, running 24/7 until burning out the defrosting elements- doesn't really do anything anyway- I defrost once every six months or so)- even then it only had a usage of 350w and only for brief periods..
(you can see the age- the plastic used to be white and has gone yellow over the years lol)
That uses about 1.2kwh a day in most weather... (measured, rather than label specs)- as fridges do not 'run 24/7' the compressor cycles- how often depends on many factors such as loading, number of times the doors are opened, how efficient the insulation is and the ambient temperature is and the like)
My sisters new one is under 100w running current- and is even larger internally than mine (just over 500L against my 430l one)- I would class neither as 'tiny' (I can't even see the top unless I stand on a chair with hers lol, and I can only just see the top of mine)
Although your 1000W inverter is right at the lower end for actually running a fridge like mine- although they have a quite low running current, because fridge compressors start 'loaded' they have a very high 'surge' or starting current- 5-7 times the running current is not uncommon (not long- less than a second) but if your inverter can't handle it, then it will send the inverter into overload shut down (LF (low frequency) inverters are much better at handling this situation than HF ones, but yours is a HF almost certainly, LF inverters in that small a range are practically unknown)
Six months if abused could indeed see a battery almost at the end of its service life (I have seen many fail after only a month or two when severely abused by people who were massively overdischarging them (and yours is a SLA- they have charging current limits that can see them failing quickly if not followed as well)- most gel/SLA batteries have an initial maximum charging current (usually less than 30A for a 100Ah rated one) which limits the wattage of panels you can handle unless you have a quality charge controller that limits inrush current on SLA settings... and often have a relatively low output current (which limits the inverter size they can handle)
I can't see the battery rating table (it is usually written on the case of SLA batteries, but that is likely a rating of 100Ah at a 20hr rate (some use a 10hr rate, but most a 20hr rate- cause it gives 'bigger numbers' and that always appeals to those without knowledge of how the battery game works)- be aware that with higher discharge rates, your 'apparent' capacity drops dramatically, so you will have far less storage than you think...
This is a smaller battery but SLA is SLA and it will scale pretty much the same..
This one would output up to 2C (ie 200A on a 100Ah battery or a 2400W inverter running at full output- which is quite high, many won't achieve this without permanent damage or a greatly reduced service life and have a current limit of 1C) but you can see that at that 2C limit, the apparent battery capacity is only about a third of its 20hr rate!!! (on your 100Ah battery it would be an apparent 35Ah of storage with a 200A draw, your current 1000W inverter draws about 83A at full power (again a massive draw through those crocodile clamps- usually about 20A/240W is their safe working current!!!) and at that rating, you will have approximately half the 'label' rating!!! or 50Ah of actual storage... assuming yours can reach that 2C rating- like I said, many are only rated at 1C, which on your 100Ah SLA is only 100A..., your current inverter is pretty much driving a 1C rated 100Ah battery pretty close to its limits if running at full output..
12VoltInstalls
life passes by too quickly to not live in freedom
My concerns with MSW go beyond the ‘mere’ electronics.
The power supplies that plug into 120VAC are not necessarily amenable regarding the 80V to 160V effective voltage range of the typical cheap inverter’s stepped sine (modified sine) output.
Pure Sine Wave (aka True Sine) is consistently in the 110-120VAC range and will not fry out the powered devices internal power supplies; we can’t predict the tolerance our cheap electronics have.
I know one smallish (700W?) microwave oven I tried on MSW made some interesting low frequency noises with a violent hum that even Steven Spielberg would have been jealous of. Yet it surprisingly worked fine plugged into a too-small 1200W psw inverter.
My first inverter was Mod Sine many moons ago. The $150-ish that I ‘saved’ was erased several times over with the cost of replacing an few items. “It worked great” - for a while. After an expensive computer monitor fizzled and buzzed I finally decided that I knew better and keeping on going was dumb. I also had a ‘dorm’ refrigerator shake and dance on the counter on a Mod-sine inverter, though it ran fine for weeks (testing for my own entertainment with only 200W of panels) on a 1200W Giandel pure sine inverter.
I’ve never bought anything but pure sine since then and never have had any device failures with PSW.
At today’s prices it’s not that costly to just buy a PSW Giandel (or better brand) and know all is well when you plug your $200 circular saw or whatever into it.
Not being argumentative, nor debating your statements. I just thought I’d expand on what you said with my perspective and opinion.
The hum you were hearing is winding hum (microwaves will work fine on MSW, but noisy- I ran one personally for over eight years on one and yeah- its humming was louder than the bells ding at the end of the cooking time- it was a very early microwave- had a windup mechanical timer!!!)- at the time I bought that inverter PSW was rare and VERY expensive- even my 2400w MSW cost over a thousand dollars at the time with PSW costing several times that!!!
In practice it takes years-decades before winding damage becomes apparent...
Both MSW and PSW will peak at the same voltage (in my case for a nominal 230v supply ie 230v RMS nominal (in practice the mains here can vary from about 220v to over 250v- which is legal and still '230v', the actual voltage peak on a 230v RMS output is 325v, if it is actually running at about 250v (common in Western Australia) the peak voltage is about 350v!!! (in your '120v' part of the world, the mains voltage is peaking about 170v-185v...)- all mains voltage are like this- be they the mains grid, MSW or PSW inverters...
Many people seem to think that the mains voltage is measured 'peak to peak'- incorrect- it is actually the RMS (root mean square) value- chosen because a 230v RMS and a 230v DC supply will both run a load at the same effective power ie a 100w incandescent bulb will look visually the same brightness on a '230v RMS' supply and a '230vdc' supply...
From Wikipedia ...
.
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Switchmode power supplies (which is 99% of the ones available today) won't be damaged (as the first thing they do is transform the incoming AC waveform (be it sinewave, square wave, triangle wave or even pure DC) into a DC supply internally usually via a full wave bridge rectifier...
The better quality ones will have a common mode choke filter in front of the bridge rectifier (marked above as EMI coil, just to the left of the four diode full wave bridge rectifier)- this will also hum slightly (very quietly) with a MSW inverter, however it again doesn't really damage them (and even if it failed with shorted turns, won't affect the performance of the switchmode in any way- indeed many ''elcheapo' switchmodes leave it out entirely (it is only to prevent harmonics from the PSU being injected back into the grid)
MSW 'could' damage transformers in 'yeah old timie' linear PSU's- these haven't been in common use since the 1990's, switchmode is almost universal (due to their ability to work on almost any voltage from about 50-70v up to over 250v without any issues), light weight and MUCH cheaper transformers (as the internal voltage step down or step up transformer runs in the multiple kHz to tens of kHz regions, rather than 50hz or 60hz)
ie anything with this label will run on AC (be it mains sine wave, PSW, MSW, or even straight DC- they would even run on a triangle wave without issue lol)
Thus a manufacturer can use the exact same PSU anywhere in the world, rather than needing one power supply for Japan (100v, 50 or 60hz depending where in the country you are) the handful of '110/120v' countries (mostly in north or central America) or the 220v, 230v or 240v (some 50hz, some 60hz)- these days all 'nominal 230v' countries- the majority of the world...
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corporal_Canada
New Member
Sorry, I meant small for me, I don't mean those office fridges.. it is a Panasonic refrigerator, and the yellow sticker on the side sais 440watts... I will see if I have a photo of it somewhere...so I believe it is day 3 of letting the charge controller feed the big 12v battery and we are still sitting at, well, there is no percentage, just a meter
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Do you have a model number for it at all- 440w still seems like an awful lot for a Panasonic...
Is that 12.6v and charging???- whats the voltage after the sun sets without any loads turned on?
12.7 is 'fully charged' while not being charged and no loads connected/turned on...
Yours is a SLA (sealed lead acid) so use the voltages in the first column for an approximate 'state of charge' and remembering that you really shouldn't be going under 50% DOD (ie 12.2v unloaded and 'rested' ie no load for at least ten minutes- for an accurate level)
If it is at 12.6 while on charge- its really flat (or your controller has gone 'boom' ad isn't working)- at 12.6v while not being charged- thats 'not quite full, but close'- about 90% full...
Is that 12.6v and charging???- whats the voltage after the sun sets without any loads turned on?
12.7 is 'fully charged' while not being charged and no loads connected/turned on...
Yours is a SLA (sealed lead acid) so use the voltages in the first column for an approximate 'state of charge' and remembering that you really shouldn't be going under 50% DOD (ie 12.2v unloaded and 'rested' ie no load for at least ten minutes- for an accurate level)
If it is at 12.6 while on charge- its really flat (or your controller has gone 'boom' ad isn't working)- at 12.6v while not being charged- thats 'not quite full, but close'- about 90% full...
12VoltInstalls
life passes by too quickly to not live in freedom
That’s assuming automotive battery parameters. The grp27 DC walmartha batteries I used for several years would ‘rest’ at 13.1-13.2; summer surface charge would be 13.8+
We don’t expect cheap dc batteries to do that because we don’t think it’s normal. The chart is still useful, but I’d want to charge much higher - well over 14V - and ‘float’ at 13.8 for best performance.
The chemistry knows nothing of human contrived charts. ‘Technically’ a 6-cell FLA isn’t ‘fully charged’ until its “absorbing” theoretically 16V+, but we don’t do that, don’t use that because it won’t hold there by nature anyways, and repetitive high states of charge shorten the lifespan of the battery.
I’d be wondering if there’s any way to hammer the battery up to 14.2-ish or more for days on end see if it will rest a bit higher for you.
corporal_Canada
New Member
6months of just keeping the solar panel clamps (alligator clip sorry) connected... And then I used the battery (discharging) for 12 hours and that's it....This is what I meant by throwing money at things before actually knowing what your actual needs are..
Which is what so many do...
And then all too many complain when they don't get the results they imagined they would..
People who know what they are doing (ie those who have studied the field extensively, or are in the actual business) will do things correctly, and can put together a system that actually works...
And knowing what your energy requirements actually are is the vital first step- then sizing the equipment needed, the panels size/number/wattage required for a specific location for the usage needed...
Your fridge is another thing that seems to be using absurdly high power- especially for a 'tiny fridge'- 440watts is literally 4-5 times the power of a modern family HOUSEHOLD fridge...
Mine here is a household fridge- over 20 years old- and the running current is 150w (I disconnected its defroster several years ago when it failed S/C, running 24/7 until burning out the defrosting elements- doesn't really do anything anyway- I defrost once every six months or so)- even then it only had a usage of 350w and only for brief periods..
(you can see the age- the plastic used to be white and has gone yellow over the years lol)
View attachment 193238
That uses about 1.2kwh a day in most weather... (measured, rather than label specs)- as fridges do not 'run 24/7' the compressor cycles- how often depends on many factors such as loading, number of times the doors are opened, how efficient the insulation is and the ambient temperature is and the like)
My sisters new one is under 100w running current- and is even larger internally than mine (just over 500L against my 430l one)- I would class neither as 'tiny' (I can't even see the top unless I stand on a chair with hers lol, and I can only just see the top of mine)
Although your 1000W inverter is right at the lower end for actually running a fridge like mine- although they have a quite low running current, because fridge compressors start 'loaded' they have a very high 'surge' or starting current- 5-7 times the running current is not uncommon (not long- less than a second) but if your inverter can't handle it, then it will send the inverter into overload shut down (LF (low frequency) inverters are much better at handling this situation than HF ones, but yours is a HF almost certainly, LF inverters in that small a range are practically unknown)
Six months if abused could indeed see a battery almost at the end of its service life (I have seen many fail after only a month or two when severely abused by people who were massively overdischarging them (and yours is a SLA- they have charging current limits that can see them failing quickly if not followed as well)- most gel/SLA batteries have an initial maximum charging current (usually less than 30A for a 100Ah rated one) which limits the wattage of panels you can handle unless you have a quality charge controller that limits inrush current on SLA settings... and often have a relatively low output current (which limits the inverter size they can handle)
I can't see the battery rating table (it is usually written on the case of SLA batteries, but that is likely a rating of 100Ah at a 20hr rate (some use a 10hr rate, but most a 20hr rate- cause it gives 'bigger numbers' and that always appeals to those without knowledge of how the battery game works)- be aware that with higher discharge rates, your 'apparent' capacity drops dramatically, so you will have far less storage than you think...
This is a smaller battery but SLA is SLA and it will scale pretty much the same..
View attachment 193242
This one would output up to 2C (ie 200A on a 100Ah battery or a 2400W inverter running at full output- which is quite high, many won't achieve this without permanent damage or a greatly reduced service life and have a current limit of 1C) but you can see that at that 2C limit, the apparent battery capacity is only about a third of its 20hr rate!!! (on your 100Ah battery it would be an apparent 35Ah of storage with a 200A draw, your current 1000W inverter draws about 83A at full power (again a massive draw through those crocodile clamps- usually about 20A/240W is their safe working current!!!) and at that rating, you will have approximately half the 'label' rating!!! or 50Ah of actual storage... assuming yours can reach that 2C rating- like I said, many are only rated at 1C, which on your 100Ah SLA is only 100A..., your current inverter is pretty much driving a 1C rated 100Ah battery pretty close to its limits if running at full output..
corporal_Canada
New Member
corporal_Canada
New Member
Oh the bird makes his NEST, sorry I didn't bother to translate 1 word, finally got it
Unless you have just rewritten the laws of physics- nope...
You missed one line...
"12.7 is 'fully charged' while not being charged and no loads connected/turned on..."
which is what that table applies to...
NOT the charging voltages- they tell you nothing about a batteries state of charge
(I would be 'extremely surprised' if any L/A chemistry battery 'rested' at over 13v- thats higher than many float chargers run at!!!)
Did you select the battery TYPE in the settings?? (most have 'preset' charge configurations in them- but you do have to tell it which of the several types available you actually have...)
They can't know what you have- so you have to tell them- they can't do a 'one size fits all'
Think of it like buying a tyre for your vehicle- you can't just walk in and ask for a 'tyre'...
you want this???
or this?
Get the wrong one- and it won't work real good (if at all)
Same with your charge controller- it needs to be set up- the manufacturers can't make a different model for every single possible combination of panels and batteries out there...
12 hours of discharging (at what load)- it would have to be a very small one to not overdischarge the battery- and again- if the charge controller isn't set right, or the panels is mismatched to the charge controller- your recharge rate could be tiny...
(assuming the panels (2x300w and 2x100w- Voc, Imp ratings??? wiring configuration???)- on a unknown generic elcheapo charge controller (ratings??? (we know its a 20A and 'probably' a PWM)- PVmax input voltage???,- type ie PWM/MPPT???)that has possibly been damaged..., with dodgy connections on top (again a possible source of damage to the controller)
urgh
We REALLY need the details- they matter...
Depending on them you could get a barely functional (if at all) system to an adequate system (those cheap PWM charge controllers with the wrong panel ratings/ configuration could be giving you barely any charge current at all...)
Properly set up, a decent MPPT charge controller with appropriately rated panels can work in practically any conditions...
eg
here's my own at the old campsite- charging a 12v battery bank, at 8AM, 100% overcast and showers all day), with the sun still down behind the trees (arrow pointing at it- just to the left of the tree on the right by itself, down in the treetops) and its already putting 4.4A into the battery bank (38-40A in good conditions)
Dawn- only half the sun visible above the horizon, panels still fully shaded by the trees, and already half an amp flowing in...
Thats off 3x 250w panels- set up properly and not that different in total power to your own (750w for mine against 800w for yours)
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12VoltInstalls
life passes by too quickly to not live in freedom
Try it. They can and do. Many, many days I came home 8-9pm to see 13.1V on my fla bank.
A ‘float charger’ doesn’t really charge, it holds a given voltage trickle. But 12.7 is too little imho
Charging fla takes a couple volts higher than static voltage to absorb.
Physics has little to do with it. Chemistry does, however.
And I haven’t rewritten anything, just related facts. I’m no chemical engineer but that is how it works. You can probably find the same white papers and theses I read years ago out there somewhere on the interestingnet to this day.
Although I’m not interested in debating a subject I’m not a well-versed expert in, I am not persuaded to defend the facts, either. Pretty sure I’ve read similar things in either this site or another offgrid power site so if you’d like to explore further you can but I’m not digging it up.
Chemistry does follow the laws of physics- and a lead acid cell (6 of in a '12v' nominal battery in series) gives a known voltage
A lead–acid battery's nominal voltage is 2.2 V for each cell. For a single cell, the voltage can range from 1.8 V loaded at full discharge, to 2.12 V in an open circuit at full charge.
In fact there are tables we use (and they haven't changed since I did my apprenticeship 40 years ago) that specifically correlate battery voltages and specific gravity levels with the state of charge... (not that you can measure the specific gravity in many batteries- not without a drill lol)
I REPEAT- I am talking about the rest voltage of a nominal 12v battery when it is fully charged- NOT on charge, not with a load connected, and 'rested' (ie neither charged nor discharged for at least quarter of an hour...)
Charging voltages are a completely different kettle of fish (and can vary with the particular type of battery in use due to the electrolytic carrier in use ie gel/AGM are quite ineffecient as electrolyte carriers and need higher charge voltages than flooded cells), but the chemical reactions involved always produce the same results in voltage output...
ScrotusGobbleBottom
Solar Enthusiast
And if the bucket is full and loads are covered, the hose is magically turned down at the prefect and real time amount for the situation.
sunshine_eggo
Happy Breffast!
Something you probably forgot since your apprenticeship (after all, it was 40 years ago - meaning you're no spring chicken)... But it's important.
Resting voltages indicating SoC are a function of time since charge was terminated. Most specifications indicate a substantial resting period - some as long as 24 hours. My Rolls FLA specify 20 hours.
It is VERY common to see FLA resting above 13.0V for at least a few hours after charge charge termination.
I prefer to leave them at least an hour- but I have never seen any hold a raised voltage for anywhere near 20 hours (even on the Rolls lol)- almost all the initial voltage drop occurs within the first 15 mins or so (maybe half an hour on cold days)
Say like the float valve in a toilet cistern or cattle trough...
Basically the charge controller is the solar version of this...
