Everything posted by Adri
-
4 Kwatt wind generator
1. How many magnets in th e rotor? What size are they? 2. What speed of rotation to generate the 4...6kW ? 3. How noisy will the generator be? I'm thinking about family and neighbours.... 4. How will your brake work? It's tricky stopping it in strongish wind... 5. Would you have it mounted on a pole/structure and at what height would it work at its best? Fascinating project.
-
Benefit of cold panels
What are "çold panels" ? How do they differ from conventional PV panels?
-
How to properly extend solar wires
Much ado about nothing. The correct sized ferrule, using a proper crimp connector - rachet type is best. Then a single shrink sleeve with 20mm excess on each side of the crimp is more than enough.
-
4 Kwatt wind generator
1. What do you expect dimensions? 2. Why MPPT instead of PWM control? And does this need feathering? (considerable increased cost). 3. What do you expect the final price to be ?
-
Renewable energy soars in 2020 despite the pandemic
I don't have figures to disprove this but Guardian's claims that 90% of new power source in 2020 is "renewable" sounds absurd.
-
Axpert fan direction
I have an Axpert 1kV/24V. The cooling fans are mounted below the heatsinks and blow downwards. I find this unusual as I would have expected the fans to blow "fresh" air UP into the heatsinks. Why would Axpert/Voltronics have done this?
-
Power Failure Reports
Which model and size Axpert King? Is the charge function running? Part of loss of grid volts could be your charger bringing down your supply voltage, but I don't give this much argument. Does this happen any day of week, or particular days? Week-end? In the last few weeks of LOCKDOWN? Where else can we find reasons for your "peak times"? When it falls to 150V, for what period? (Don't know the spec's for your area, but they have rules where they can drop out for 1mS (?) without you complaining about it. Others will know better.
-
Axpert settings for LiFePO4
I once converted a mains-type lead light (the workshop type, for working under cars) with a standard headlight bulb where the low-beam filament had burned out, with croc clips. Turned out to be the best 'rough' load for many 12V (and less) applications, like testing batteries and chargers. Particularly because of the steel wire lamp protection cage-design.
-
"constant current" ?
To you and me that makes perfect sense. I just wonder how a beginner/novice will understand the concept correctly. Hence my query. What makes sense? How will these folk interpret CC / CL? (Spoken or written science, interpretation, etc....)
-
"constant current" ?
The phrase 'constant current' (CC) (regarding the bulk mode of charging most batteries), when is it "constant"? Do you NEED to charge batteries at THIS current, and no less? Or can we charge said batteries at lower value current but not exceed this value? (Ex.: Ni-Cads must be charged at CC for a fixed time to be fully charged.) Or do they/we mean "current limit"? (meaning to limit the maximum current.) As I read it if I have PV rated less than the required/specified CC I will never meet the CC rating of the particular type/size of the battery with my particular setup. In theory therefore I should never expect to reach beyond the bulk charge point to charge this (or any) particular battery. On the contrary, if my PV can only produce (some) less Amps than the CC rating I should still be able to reach the bulk voltage point, but it will take a while longer. If this is true then it should in theory be called "current limit" (meaning in effect "Do not / cannot exceed CC rating") and not "current control". Some would call this nit-picking, but I prefer to know what "they" mean correctly, to better understand "them" and what "they" are saying. (Perhaps it's a shade of "fake news" we're bombarded with daily...)
-
Sun tracker
huh...? (Phew....!)
-
Balance and de-sulphating Trojans
The importers of these Trojans ship the batteries filled with electrolyte and ready-to-use, by sea freight. The first series I bought I measured on delivery at (average) 6.70V no-load and 6.55V @ 5A load after 5 minutes : acceptable in my opinion. I would expect some self-discharge during shipping, storage and "shelf" before sale/delivery, typically 2%/month. I don't know who imports batteries dry because the weight difference is insignificant compared to the weight of the nett battery - let alone the type and quality of electrolyte available locally. (I can imagine the hassle with quality/guarantee of the product by manufacturer after filling with possibly dubious stuff.) [Aside : some batteries I bought in the past, typ. 12V 20Ah were shipped 'dry' from China and it took me some time to find a good electrolyte (Protea Chemicals).] I asked my original question to hear if someone had experience of managing this procedure (or variations) and their results. By the way, the site is www.trojanbattery.com and no other.
-
Balance and de-sulphating Trojans
I now have 4 x Trojan T105 (6V) resting, i.e. not being used for 3 months until next project. I connected the string directly to 2 x SOLARWORLD PS 150 pv's (wired in series) to boost the batt's for balance and de-sulphating without a controller/regulator. I have been monitoring cell electrolyte levels and have topped up regularly with de-ionised water. After a few hours of good sunshine it reaches 31V, so I imagine a total of 6 hours of charging. After overnight "rest" next morning I read 25.4V. Is this useful and acceptable? Can / should I do this regularly? Once a week?
-
Axpert settings for LiFePO4
A very good reply weber and much thanks for it. You're quite right that the right option is to properly balance the batteries with suitable connection philosophy. In my case charge current is mostly less than 10A from either source, and load current is max. 16A ever, so I wonder if my imbalance is SO important in my installation. (Perhaps I'm lazy in my old age..?) I wonder if I alternate the main supply/take-off line from Axpert from first of the two batteries (call it "prime" battery) to 2nd battery ("slave") as internal connection of the 2 x Anderson plugs are parallel-connected inside the battery housing, say, once a week, we may achieve the right balance after some cycles? (Thanks, again.)
-
Balance Batteries
When you say 'disconnect' then the charging voltage would be too high, unless you 'retune' the charge system. Or do you mean parallel connected batteries in which case you don't have to worry about 'retuning'?
-
Axpert settings for LiFePO4
Yes, Weber, using those same Anderson plugs with 12mm2 cables. One pair direct connection from Batt1 to Axpert terminals = 1.7m. (Added 1.5mm2 wires at each end of the black cables for current reading and a red wire for V for my Mooshi - I can monitor the battery behaviour easily at the kitchen table.) Then same kind cable/Andersons from Batt1 to Batt2 (0.9m). Read your good stuff about the proper way to interconnect, but figured with such heavy cables it may not be necessary. Please correct me if I'm wrong/comment.
-
Axpert settings for LiFePO4
I have 2 x AKKUTECH 25.5V 100Ah in parallel using the Anderson "parallel" plug (with 8mm2 cables throughout). Do you think it's necessary to re-wire so that it's according to your idea or can I continue in this way? I would like to balance the cells for longevity. What's your feeling here?
-
Axpert settings for LiFePO4
After some more fiddles, settings are now : 2 = 20A 11 = 20A 12 = 25.5 13 = 25.5 26 = 29.2 27 = 29.0 29 = 24.0 ( setup : 4 SolarWorld SP150, AXPERT 1K-24, 2 AKKUTECH 25V 100Ahr) I see battery voltage rises to 29.0V before charge current tapers off [to float value?] but seldom exceeds 29.1V (measured on Mooshi). Now on SOL (setting 01), reads 140W (29.1V, 0A) with fridge load, running, TV, decoder. Am I being risky? Label reads "CC at 0.2C to 28.4V". Are they not deliberately down-specifying as 'excessive protection limit'? I would wonder at what voltage the capacity is measured (100Ah)?
-
'Series-parallel' vs 'parallel-series'?
It's a case of six of one and half a dozen for the other.
-
Writing own monitoring software
I'm very interested. I don't have anything monitoring my system except a Mooshimeter (MM) to simultaneously show current (bi-direction) and battery volts. (The AUXILIARY VOLTAGE DC = shunt-connected wires directly to MM, about 5mV/A.) This tells me lots but I would prefer to have still more information. Please can you update me about your progress? Thanks, A
-
Power Failure Reports
I don't understand what I'm being told. Monday 13 Jan.2020 I'm told about 25% of ZA population went back to work, factories started production after the Xmas month break and one scientific journal expected a min. of 28% increase in electricity usage over the December 2019 period. What with wet coal, inferior quality coal and broken conveyors and more bad news, what happened? On Sat. 11 and Sunday 12 Jan.2020 we had two 2-hour blackouts (Durbanville) each but from Monday until now (Wed. 15 Jan.2020) no interruptions at all! What did I miss? Did ESKOM fix everything over the weekend? Or was there some what our brother Donald calls "fake news"? Confused, am I.........
-
Pay licence fees for your generator or solar panels!
I'm not sure about this Level 6. Does it mean up to 10 hour blackouts/day? How will cell-towers/repeaters handle this? I understood that MTN has back-up for 4 hours. What happens then? Do these towers shut down and then come back when ESKOM returns? It sounds like a major catastrophe to me.
-
Power Failure Reports
What about this "level 6" which I understand means up to 10 hours per blackout stretch? Does this mean totally uninterrupted blackout for (possibly) 10 hours? Per day? Tomorrow Mon. 13 Jan. 2020 and "start-up" for builders and many workers, factories, etc. If ESKOM is in dire need of 6,000MW this must be the start of total catastrophe. And what about the thousands of cell towers? I understood that they are (battery back-up) equipped to carry phone/data traffic for "up to" 4 hours. What happens next?
-
Pay licence fees for your generator or solar panels!
Regarding registration I like the rule of : grid-tied, OK grid-free NO
-
Generator connection advice
Yes, the yellow/green wire is always metal/ground wire for protection and connect to E (earth). The white & brown wires are floating output. If the gen is fitted with standard ZA 3-pin sockets it must show 230Vac output. His sparkie could verify this quickly using a DMM and a simple load like a standard kettle in a few seconds. If his installation with a standard 63A change-over switch and suitable connector and normal testing he would be able to sign the COC. If the gen is fitted with the standard ZA 3-pin socket it most certainly is set for 230V 50Hz (= 3000 rpm) so no need to worry about re-configuring the alternator connections.