Hi everyone,
Been hovering as a guest for several months. Now I am this close (>>.<<) to purchasing both a Classic 150 and Classic Lite 150.
Recently I installed a 48v 1000Ah VRLA (AGM) batterybank made up of 2v cells to replace the existing failing 24vdc batteries.
My question is this... the existing 24v setup outputs 3000watts (120amps cont.). In the meantime until the panels are reconfigured for the new 48vdc system and another 3000watts of panels and a Classic Lite are added, can I just plug the 24vdc into the Classic 150 and boost the output to charge the 48v battery bank? The bank desperately needs a charge/float (current avg. of 2.08v per cell).
So I read that the Classics support BOOST mode but it's still not clear to me if I can do this and at what efficiency?
Thanks in advance.
Okay, this is an excerpt from what I found in an online .PDF by Robin Gudgel created circa 2007 ->>
-----------------------------------------------------------------------------------------------------------
Classic MPPT product overview
(Development status update)
12. Boost or Buck: MPPT controllers take a high voltage and buck it down to the battery
voltage. What if you want to go the other direction and charge a 24 volt battery from a 12
volt battery? No problem. The Classic can be configured as a boost converter too. This
feature is not found on any present day charge controller.
-----------------------------------------------------------------------------------------------------------
http://www.midnitesolar.com/pdfs/classicDevUpdate3.pdf (http://www.midnitesolar.com/pdfs/classicDevUpdate3.pdf)
It's great news to find this info as it's exactly what I need for my application!!!
However, before I go off and order two 150's, perhaps one of the Midnite Solar devs would be so kind as to confirm the feature in the Classic 150 and tell me where I can find the specs regarding the boost efficiency & maximum current when stepping-up a nominal 24vdc supply to charge a 48volt AGM battery bank?
Thanks again.
I am pretty sure one of those guys will get in here to answer your question. They usually respond very quickly to this type information request. The probably just haven't been on the forum since your first post on it. I will poke Ryan and see if he can help.
Personally, I do not know.
Good luck with it.
Tom
At this time the Classic is really a Buck only controller, while the hardware can boost there is no software to support that just yet.
Ryan
Hi, that's a real downer. <slowly puts wallet back in pocket for the moment>.
Anyone else have any ideas on how to get around the issue until I can sort it out properly in June? Trying to avoid a 5kva 48vdc battery charger, fuel noise etc. when I have nice quiet PV's idling away up there.
Please tell me someone in the know... Is there actually a charge controller out there that will do the job? I've only drawn blanks so far.
Thanks again.
Quote from: psyfy on January 16, 2013, 09:19:06 PM
My question is this... the existing 24v setup outputs 3000watts (120amps cont.). In the meantime until the panels are reconfigured for the new 48vdc system and another 3000watts of panels and a Classic Lite are added, can I just plug the 24vdc into the Classic 150 and boost the output to charge the 48v battery bank?
It sounds like all that's required is just to reconfigure your panels. Something you need to do anyway and once the panels are reconfigured and if you have a classic, then you can connect it to the 24v battery and it'll work fine. Then you can disconnect it from the 24v bank and connect it to the 48v bank and it'll auto detect battery voltage and charge that bank. Simples :)
Quote from: stephendv on January 17, 2013, 01:20:10 PM
It sounds like all that's required is just to reconfigure your panels. Something you need to do anyway and once the panels are reconfigured and if you have a classic, then you can connect it to the 24v battery and it'll work fine. Then you can disconnect it from the 24v bank and connect it to the 48v bank and it'll auto detect battery voltage and charge that bank. Simples :)
Thanks Steve, however things are never that simple. The roof (and therefore the panels) all come off in summer as another level is going up. Then the both old 3kw and the new 3kw arrays go up.
Just wanted to avoid doubling handling and unnecessary costs. Will think about it.
Quote from: Halfcrazy on January 17, 2013, 10:34:30 AM
At this time the Classic is really a Buck only controller, while the hardware can boost there is no software to support that just yet.
Ryan
Software? I don't get it, you're almost there! 2007 and 2010 are long gone in the tech field and vaporware just isn't cool. Outsource it!
Boost is a killer function, this is your goose. Don't drop the ball.
Best.
if the battery bank is not in use i'm sure you would probably be able to charge it up 1/2 at a time.
as to the pvs, you aren't going to get around the rewire, but it isn't as complicated as you make it sound.
Quote from: niel on January 17, 2013, 09:10:34 PM
if the battery bank is not in use i'm sure you would probably be able to charge it up 1/2 at a time.
as to the pvs, you aren't going to get around the rewire, but it isn't as complicated as you make it sound.
..or just rewire the batteries temporarily as a 24 volt bank
dgd
Yeah, this still may happen but it is just not high on the list. There are too many more important things to do at the present time and not enough resources (engineers) to get it all done.
I thought that solarconverters.com made what you want but I just looked and theirs is 12V to 24V. There are other companies out there that must do this if you can't wait. I just don't know where right off the top.
boB
I'm with DGD, just reconfigure your battery bank for the time being, likely they haven't been discharged much, AGM's hold a charge particularly well, so in the short term you won't need too heavy a wire since you CC will realise they are in the top 5% and reduce the current.
Alright, you've all been really helpful. I'll take a look at things over the weekend and get back to the forum.
Regards to all.
Quote from: Psyfy on January 17, 2013, 09:08:37 PM
Quote from: Halfcrazy on January 17, 2013, 10:34:30 AM
At this time the Classic is really a Buck only controller, while the hardware can boost there is no software to support that just yet.
Ryan
Software? I don't get it, you're almost there! 2007 and 2010 are long gone in the tech field and vaporware just isn't cool. Outsource it!
Boost is a killer function, this is your goose. Don't drop the ball.
Best.
love the mixed metaphors :) ...but couldn't agree more, the h/w is excellent, the s/w is woefully behind, outsource or better still make it open source
dgd
Quote from: dgd on January 18, 2013, 03:32:20 AM
love the mixed metaphors :) ...but couldn't agree more, the h/w is excellent, the s/w is woefully behind, outsource or better still make it open source
dgd
Yep, looks like the kinda device that should be running Ubuntu! haha
Quote from: niel on January 17, 2013, 09:10:34 PM
if the battery bank is not in use i'm sure you would probably be able to charge it up 1/2 at a time.
as to the pvs, you aren't going to get around the rewire, but it isn't as complicated as you make it sound.
1/2 at a time? Thanks but it's a muck around with a 50kwh battery. CC's like the Midnite current sources right, so 12v@~100a=1200w, 24v@~100a=2400w & 48v@~100a=4800w.
So 48v will adequately cover the C10 recharge rate but 24v will take twice as long. At $5- a Gallon of Gas for the 10kva genset, that makes a bit of a difference.
Though does it really matter? Nah! Just being pedantic I guess. :)
Quote from: boB on January 18, 2013, 02:14:56 AM
Yeah, this still may happen but it is just not high on the list. There are too many more important things to do at the present time and not enough resources (engineers) to get it all done.
I thought that solarconverters.com made what you want but I just looked and theirs is 12V to 24V. There are other companies out there that must do this if you can't wait. I just don't know where right off the top.
boB
I hope so.
Hey, I been having a chat with some others and realise that I also have the option to rectify 110vac(RMS) to 154vdc @ 40a (~4kw). Tell me, which input on the Classic (and which model) will take this input.
Is the output from the Classic to the Battery bank PWM?
What would be the charge rate for 154dc@40a?
Is the Classic configurable as a 'Constant Current Source' so that 'Max Amps' can be defined?
Thanks.
Quote from: mtdoc on January 18, 2013, 03:09:22 PM
Quote from: dgd on January 18, 2013, 02:42:06 PM
However, the concept of the LITE Classic with all the display, setup and logging software done externally is the future..
Just need the iphone app, a simple version of the local app that shows Classic activity :)
dgd
Already easy to do this with VNC. I run Remoter on my iPhone and can access the Local App anywhere, anytime. 8)
yes, I already do this and it really works well. Its just the local app running on the 'home' laptop disconnects too often for my liking.
Also also just too many 'unresolved features'.
An iphone app just showing the meters part would be good for me.
dgd
Quote from: dgd on January 18, 2013, 04:32:23 PM
yes, I already do this and it really works well. Its just the local app running on the 'home' laptop disconnects too often for my liking.
Hmm. I haven't had any disconnect problems.
Quote
Also also just too many 'unresolved features'.
An iphone app just showing the meters part would be good for me.
dgd
I agree a simple iPhone app would be fun.
For me I want to access more than just the Classic data. Nice to be able to monitor my whole system -- Inverter, Grid/genset and AC usage data, etc - also my weather station data. Now. if I could just get all that to run on a Raspberry Pi - I'd have a really low cost, low power solution.
Quote from: Psyfy on January 18, 2013, 07:23:48 AM
Quote from: niel on January 17, 2013, 09:10:34 PM
if the battery bank is not in use i'm sure you would probably be able to charge it up 1/2 at a time.
as to the pvs, you aren't going to get around the rewire, but it isn't as complicated as you make it sound.
1/2 at a time? Thanks but it's a muck around with a 50kwh battery. CC's like the Midnite current sources right, so 12v@~100a=1200w, 24v@~100a=2400w & 48v@~100a=4800w.
So 48v will adequately cover the C10 recharge rate but 24v will take twice as long. At $5- a Gallon of Gas for the 10kva genset, that makes a bit of a difference.
Though does it really matter? Nah! Just being pedantic I guess. :)
You have an AGM battery which has the characteristics of a low self discharge 1-2% per month, so You need just 40 ampshours at 24V to fully charge per month, It would take less time than reading this thread to reconfigure your bank, unless it is lead casted.
Furthermore, since your charging the top 5% of the battery capacity, you won't/shouldn't be charging at C10 and since your applying such a low current, you really don't need super heavy cables, if that's what your worried about.
If I've followed this thread correctly you just want to maintain/top off the battery and you have no applied loads. Sounds like your making a mountain out of a mole hill.
"so You need just 40 amps at 24V to fully charge per month"
Please use the right terms when giving advice, 40 amp HOURS is what is needed, not 40 amps per month, 40a/month would be 28800 amp hrs. I am not trying to be pedantic here, but it is important to use the correct terms to avoid confusion.
Quote from: dbcollen on January 21, 2013, 11:16:29 AM
I am not trying to be pedantic here,....
Well, you certainly are, ...but your also correct! I changed it.
Thanks, just seems like the OP is trying to make this a big complicated thing, when it doesn't take much to maintain AGM batteries.
Quote from: Photowhit on January 21, 2013, 02:19:51 AM
If I've followed this thread correctly you just want to maintain/top off the battery and you have no applied loads. Sounds like your making a mountain out of a mole hill.
Hey thanks Photo-what-not! Now listen, I'll paint you a picture whilst I sip my morning coffee...
1.) The property is in Trinidad, CO. It's already two floors up, with a third to go on. You guys have heavy snow this year too right???
2.) I am currently in Australia and return in June. In contrast, it was nice, mild 107F here on Friday. I travel a lot, too much in fact, not enough time at home where the Buffalo roam etc. In fact, the last 18 months have been spent backward and forward to Frankfurt, Valencia, Austria, Prague and many other places.
3.) Besides the weather being a partial issue, the person babysitting the CO property isn't really the one to go around doing a rewire of batteries or a panel reconfig on the roof. Aside from the four feet of snow and 4F temperature, my grandfather is 87 next week.
4.) However, he could install a new CC as he was an engineer "back in the day" (don't think even the Mayan calendar goes back that far :) ) but he's not so quick on his feet these days, if you know what I mean. At least the battery part of the 'shed' is heated. Actually, he'd love it if I asked him to do it.
5.) 48v/1200Ah (48*3.2v/400Ah cells) of LiFePo4 batteries arrive in June. Can't wait to build the BMS for it as a lot of the stuff on the market is just crap. To use one would be like entrusting Charles Manson to babysit your kids. A BMS really only has three tasks, Undercharge, Overcharge and Cell Balancing. It's how it is done that counts and the quality of the design. Mine's based on a Atmel AT16. Got a tape reel of those things and need to keep coming up with creative, non wasteful ways to use them. SMD and not PTH IC's you see.
6.) The 48v/1000Ah VRLA AGM's will be retired and sold off. That is already a done deal. Naturally, I want to keep them in shape.
7.) Two weeks ago, I had someone (an installer) from Denver drive down there to sort it all out, said he could do it when I spoke with over the phone from here. Well, he couldn't work it out. Probably because among other things, I run a modified an APC UPS10000 10KVA UPS as the main inverter with another 1000watt SineWave inverter running through the AC input of it.
Here's how it works... When the small inverter output sags below 90vAC, a custom uP based design of mine disables it's H-bridge, it shuts down and the 10KVA UPS takes over within 20ms. All equipment remains blissfully unaware of the changeover.
When the load on the 10KVA UPS drops below 10%, the same logic re enables the small inverter. The UPS sees AC on the AC input and graciously hands controll back to the 1kw inverter. As an aside, I designed the UPS into the as I bought it from a client for $100. Increased the surface area of the heatsinks so that it could deal with continuous full loading if required.
I mean, wouldn't you do the same, if you knew what you doing?
There are a few other tricks such as the AC coupling of two 3kw Grid-Tied inverters (that I repaired, they cost $35- each from eBay) facing the UPS/inverter during daylight hours. However, that is an entirely different story. I only mention it so that you may better understand that it is not so easy to just go about reconfiguring the system in my absence.
8.) Finally, I'm a Mechatronics Engineer (B.Eng(Mechatronics) who's speciality is embedded systems, microcontrollers and PLC's. I also code some desktop apps in .NET(C#) with SQL (of course. At the moment I work with data telemetry designs.
9.) Yesterday I bought a Classic LITE 150 to hack about with. Why not I though. Sure, it doesn't boost as the literature frustratingly lead me to believe but hey, who does...
To backtrack... I didn't paint a picture to begin with as frankly, when last on this forum it was my day off and I don't really have much time... and yes, it's true, Vaporware irks me. 22 years in the electronics/computing/design industry has made me bitter. hahaha
Anyway, there you have it, nine points of rambling. Hope that is enough to silence the bitches! ;)
The truth will set you free,
I don't want to try to follow what is going on with your system.
It appears I have answered questions for the "vaporware" questions, so... If you consider them "bitches" don't look at me, I think the wasting of my time would entitle me, but let a community solve real problems, and it works...
As one of the 'bitches', I suppose,
I have nothing to add.
Quote from: cpm on January 21, 2013, 06:52:59 PM
As one of the 'bitches', I suppose,
I have nothing to add.
hahaha. No problem, all good. So I'll leave it there and add to the body of knowledge when there is something worthwhile to contribute...
Over and out.
Quote from: Photowhit on January 21, 2013, 05:34:21 PM
The truth will set you free,
I don't want to try to follow what is going on with your system. nny
Funny that, I had two smartly dressed people at my door telling me the same thing..
Quote
It appears I have answered questions for the "vaporware" questions, so... If you consider them "bitches" don't look at me, I think the wasting of my time would entitle me, but let a community solve real problems, and it works...
Good point. But I suppose we did learn, yet again, that the Classic is an ongoing development project. No boost. And no resourses at Midnite to add this functionality any time soon. :o
We did get some interesting off topic discussion about reporting software and cpu hardware. Much better than other message threads that descended into hard liquor or worse still 'the dogs' complete with dog pics ;D
dgd
Quote from: Psyfy on January 22, 2013, 01:30:50 AM
Quote from: cpm on January 21, 2013, 06:52:59 PM
As one of the 'bitches', I suppose,
I have nothing to add.
hahaha. No problem, all good. So I'll leave it there and add to the body of knowledge when there is something worthwhile to contribute...
Over and out.
No, please don't become a lurker again.
Maybe let us know about your ideas for a LiFePO4 battery management system when you start designing it.
dgd
QuoteMuch better than other message threads that descended into hard liquor or worse still 'the dogs' complete with dog pics
Great!
Post sheep pics if you prefer...
Erik
Quote from: SolarMusher on January 22, 2013, 08:43:56 AM
QuoteMuch better than other message threads that descended into hard liquor or worse still 'the dogs' complete with dog pics
Great!
Post sheep pics if you prefer...
Erik
Don't get me wrong. I was not complaining, I actually quite enjoyed the diversion to the dogs that you started with those excellent pics of your
'pack'. I, for one, like to see some of the 'bigger' picture including lifestyle and interests of others in this business. I just wish I had some of your snow and ice here right now, the heat here is too much...
dgd
Quote from: dgd on January 22, 2013, 03:06:53 AM
Quote from: Photowhit on January 21, 2013, 05:34:21 PM
The truth will set you free,
I don't want to try to follow what is going on with your system. nny
Funny that, I had two smartly dressed people at my door telling me the same thing..
Quote
It appears I have answered questions for the "vaporware" questions, so... If you consider them "bitches" don't look at me, I think the wasting of my time would entitle me, but let a community solve real problems, and it works...
Good point. But I suppose we did learn, yet again, that the Classic is an ongoing development project. No boost. And no resourses at Midnite to add this functionality any time soon. :o
We did get some interesting off topic discussion about reporting software and cpu hardware. Much better than other message threads that descended into hard liquor or worse still 'the dogs' complete with dog pics ;D
dgd
dgd, About the 'truth' comment,... I'm a newby here, but have been an active member of solar forums for years, even before the WWW on the Usenet bulliten boards. Incomplete information makes things difficult, but wrong information makes for wrong answers and wastes the time of people who are part of the community.
Quote from: Photowhit on January 22, 2013, 05:36:19 PM
dgd, About the 'truth' comment,... I'm a newby here, but have been an active member of solar forums for years, even before the WWW on the Usenet bulliten boards. Incomplete information makes things difficult, but wrong information makes for wrong answers and wastes the time of people who are part of the community.
yes, the information was wrong and time wasting. :(
From my experience back to Fidonet and Usenet BBS days in the early 90s there are always people asking for advice/help who withold all the relevant info. They are either naive or deliberately mislead and when they eventually tell all it annoys those who invested their time trying to be of assistance.
dgd
I cannot find any mppt solar controller anywhere that offers voltage boosting.
Quote from: dgd on January 22, 2013, 06:17:08 PM
yes, the information was wrong and time wasting. :(
From my experience back to Fidonet and Usenet BBS days in the early 90s there are always people asking for advice/help who withold all the relevant info. They are either naive or deliberately mislead and when they eventually tell all it annoys those who invested their time trying to be of assistance.
dgd
I cannot find any mppt solar controller anywhere that offers voltage boosting.
1.) Hi, FYI... I found an MPPT boost controller (an Australian product). Had one of these puppies shipped home last week and will be certain to let you all know how it works out.
-->> http://www.gsl.com.au/bmppt1500.html
2.) Wrong info. Community? Time wasting?. Nah... I call it tarnished pride when someone realizes that Grandma already knows how to suck eggs... <shrug> <wink>
Psyfy
Quote from: Psyfy on January 31, 2013, 11:31:17 AM
1.) Hi, FYI... I found an MPPT boost controller (an Australian product). Had one of these puppies shipped home last week and will be certain to let you all know how it works out.
-->> http://www.gsl.com.au/bmppt1500.html
2.) Wrong info. Community? Time wasting?. Nah... I call it tarnished pride when someone realizes that Grandma already knows how to suck eggs... <shrug> <wink>
Psyfy
Just remember what "NET" means. Not Entirely True"... Which is true sometimes. Or a lot of times ??
This product looks interesting ! It doesn't say if it is MPPT though. I would imagine that it is.
They don't say specifically if it is also good for charging a higher voltage battery from
a lower voltage battery.
Does it charge a 12V battery from 12V PV ? Or 24V battery from 24V PV ? It would have to be a buck-boost to do that I think.
Also, 58 volts maximum for a 48 volt battery is slightly too low. It still looks
like it has some great uses.
Yes, please let us know how this works. I will gladly recommend it to those few customers
that really need such a beast. That is, if it is fairly reliable.
Thanks for finding that !
boB
Quote from: Psyfy on January 31, 2013, 11:31:17 AM
1.) Hi, FYI... I found an MPPT boost controller (an Australian product). Had one of these puppies shipped home last week and will be certain to let you all know how it works out.
The working voltage limits sort of reduce its potential usefulness, look forward to your review of it.
Quote
2.) Wrong info. Community? Time wasting?. Nah... I call it tarnished pride when someone realizes that Grandma already knows how to suck eggs... <shrug> <wink>
Yes, community is correct. Nothing to do with tarnished pride, just a minor annoyance that could have been avoided with better info.
Sadly some in the community may feel less willing to assist in future.. :(
dgd
Quote from: boB on January 31, 2013, 01:58:46 PM
Just remember what "NET" means. Not Entirely True"... Which is true sometimes. Or a lot of times ??
LOL ! Especially when passed through the filter of the Eastern marketing machine! I'm sure that we are all familiar with that brand of disappointment...
What's interesting is that I met this guy at http://eastsolar2012.com/ last year (Lindsay Jones). What's refreshing is the 'Old School Engineer' values. They demo their products (nothing as pretty as the Classic to look at BTW but solid none-the-less) on the stand with a CRO, Multimeter and C/Vlim PSU so that the informed can determine what's going on straight away.
Anyway, what I am trying to say is that his claims are on the conservative side. However, I don't have one in my hands right now to be 100% convinced but time will tell.
Quote
This product looks interesting ! It doesn't say if it is MPPT though. I would imagine that it is.
The model is a BMPPT1500. So yes, it translates to 'Boost Max Power Point Tracking @ 1500w' or some such.
Quote
They don't say specifically if it is also good for charging a higher voltage battery from
a lower voltage battery.
Does it charge a 12V battery from 12V PV ? Or 24V battery from 24V PV ? It would have to be a buck-boost to do that I think.
This is an interesting point. On the list of website product specs it mentions that the Min(Vmp) as being 14vdc and that lower values are possible but subject to MOQ's. In any case, does it 'Boost' or 'Buck' or 'PWM'? Can't be certain but I did just send an email to GSL with the question.
The product cost me USD417.00, shipped (converted from 395- Aussie bananas). :)
Quote
Also, 58 volts maximum for a 48 volt battery is slightly too low. It still looks
like it has some great uses.
Apparently, this param is adjustable via firmware and the included app. Up to what point though, I don't yet know.
Quote
Yes, please let us know how this works. I will gladly recommend it to those few customers
that really need such a beast. That is, if it is fairly reliable.
I sneaked a peek inside one of the boxes at the Expo and it's built with 2oz Cu PCB, STMicro's, generous cooling, solid connectors etc. Don't worry. The first thing thing that I will do when I have the chance is to put a CRO on it and see what makes it tick.
Quote
Thanks for finding that !
boB
Too easy.
Quote from: dgd on January 31, 2013, 05:50:38 PM
Yes, community is correct. Nothing to do with tarnished pride, just a minor annoyance that could have been avoided with better info.
Sadly some in the community may feel less willing to assist in future.. :(
dgd
John Boy n community, y'all grab ya pitch forks now an follow me an Jenny Sue to the field where we gonna have ourselves a right proper lynching an a hoedown after wid dem good ol boys.
Seriously though, don't sweat it. Small towns (communities) make a lot of us nervous. LOL!
Psyfy.
Thanks Psyfi !
There is another thread on this same CC on the NAWS forum...
http://www.wind-sun.com/ForumVB/showthread.php?18653-DC-DC-Boost-converter-MPPT
I just posted this and will repeat it here just because...
boB
A boost type of charge controller would certainly be interesting ! Instead of worrying about PV input voltage drop from array to charge controller, the opposite might be the case if the batteries are a long ways away from the batteries... Instead of putting the CC near the batteries and optimizing the PV input wiring, you'd want to place the CC near the array and optimize the cable run to the batteries in which case the wire size would be larger and cost more than it would with a typical buck type charge controller.
Doesn't sound like the most efficient method but I suppose it has its uses.
boB
Quote from: boB on February 01, 2013, 01:33:35 AM
Thanks Psyfi !
I just posted this and will repeat it here just because...
Doesn't sound like the most efficient method but I suppose it has its uses.
boB
Everything is a compromise. Ohm, Voltaire, Tesla, Faraday and whoever else will attest to that! ;)
I think that in a previous post I may have mentioned that my HV strings (+200vOc) are fed into an AC coupled MPPT Grid-Tie inverter. This obviates the entire LVDC voltage drop/distance equation. The Sunny Boy is about 99% eff. on the MPPT side and ~96% eff. electrically. Think about it, -4% and builders three core instead of 4/0 @ ~1%+? Take your pick...
My interest in 'Boost' is to solve a problem, today. Later it will not be as important but it is right now. So, when I did a product search and Googled the specs for the Midnite Solar Classic 150 and learned that it had 'Boost', I yelled Eureka. However, this was not to be... I still don't understand why this function was discussed nearly three years ago and given a bit of a rave by you guys in print. If it was a software-only issue, why it didn't make the grade? Must be, has to be, a more complex issue than software...
As an aside, a Classic 150 LITE arrived in the post today with my name on it. Nice looking unit and surprising in it's compactness and bantam weight. Now, if you'll excuse me, I have Mango and an Acer A500 to setup in lieu of the LCD. :)
Psyfy
Quote from: Psyfy on February 01, 2013, 05:35:08 AM
If it was a software-only issue, why it didn't make the grade? Must be, has to be, a more complex issue than software...
Psyfy
Yes, that is exactly it. Just harder to do (properly) than expected. It can still be done and has been done but it is a bit too dangerous at the moment
to call it a feature until we can regulate the voltage and power a bit better. Most of that is just software.
Boost mode is still on the list of future features though. Just not yet.
boB
Quote from: boB on February 01, 2013, 01:33:35 AM
A boost type of charge controller would certainly be interesting ! Instead of worrying about PV input voltage drop from array to charge controller, the opposite might be the case if the batteries are a long ways away from the batteries... Instead of putting the CC near the batteries and optimizing the PV input wiring, you'd want to place the CC near the array and optimize the cable run to the batteries in which case the wire size would be larger and cost more than it would with a typical buck type charge controller.
Doesn't sound like the most efficient method but I suppose it has its uses.
boB
Just as a follow up on all of this;
1.) For sure! I think that AC coupling is a better solution to the issue of 'PV to Battery Bank' voltage drop, conductor costs and system weight over that distance. So, what about if, just for shits and giggles we were to;
a.) Take the output of a given PV array and feed all of it's output into the MPPT inputs of a size-matched GTI.
b.) Send the GTI AC output from point A to point B via standard building flex and into a subpanel that also has a forward facing OGI feeding into it.
c.) Distribute the AC to loads from that subpanel and dynamically calculate the Demand/Load ratio with a uP.
d.) Take and post-load AC surplus and feed it back into a 3KvA5 CLim AC/DC SMPS with a stable 'Drooper' curve of ~96% eff. and a Nom. 67vdc/65A output.
e.) Feed that SMPS CLim DC output into the DC PSU input of a CC ,such as a Classic LITE 150 and charge a 48v battery bank.
f.) Use the aforementioned uP to also calculate at a DC shunt and do two things with that info;
1.) Dynamically adjust the SMPS output to match the AC load surplus.
2.) Divert any AC surplus into the booster of a SHWS, instead of just wastefully dissipating into the open air as most seem to do.
Oh hang on... I just described my setup....
Of course there are losses;
~1% GTI MMPT.
~4% GTI elec. eff.
~6% OGI @ 92%(Load)
~4% SMPS.
~2% Misc sys. losses.
Then there's the ~-20% on the 50KWh AGM battery bank but hey, what can one do...
On a 6KvA PV array that's ~4 250W panels (or $800 @ ~$0.80c p/watt or about 10c per day over 25 years (taking reduced panel output into account) to cover those losses but on the upside, you save a lot in copper, can locate the array away from the batteries and enjoy ~10KvA when the sun is shining and ~5KvA when it's not. :)
Psyfy.
OMG and I thought my system was complicated :o
What a relief to find there are others further up the looney tune scale than me :P
dgd
Quote from: Psyfy on February 01, 2013, 12:29:52 AM
Seriously though, don't sweat it. Small towns (communities) make a lot of us nervous. LOL!
Psyfy.
And the flawed logic of most of the big city folks that have lost any connection to nature and how the world really works scares the holy crap out of most of us country folks, especially considering the city is the population base and the ones who decide the new laws.
Quote from: dbcollen on February 08, 2013, 08:17:34 PM
And the flawed logic of most of the big city folks that have lost any connection to nature and how the world really works scares the holy crap out of most of us country folks, especially considering the city is the population base and the ones who decide the new laws.
Ahem, off topic reply but I do enjoy Social Philosophy too <coughs into hand>.
You can have the best of both worlds you know... <shrug> Let it be known that the flawed logic of which you speak extends to those parents who move out of the cities to raise their family. Ironically, only to have their children fight tooth-and-nail to get back into the city that the parents ran away from in the first place. The challenging ones will always want leave the cows behind to immerse themselves in and imbibe the city's myriad inherent sophistications. Not all parents encourage this as they tend to too easily forget that it's not about them anymore and project their own needs and wants onto the shoulders of the hapless next generation.
The cycle repeats ad-infinitum.
Fact is, if you want easy access to toys like those spoken about on these forums and associated gadgets, along with a few other ones at the same time, you know, like homes, travel, cars, skiing/boarding, good wines etc. and if you choose to learn a skill at the highest eschelon, then IMHO, one really does have somewhat broader choices regarding profession and lifestyle offered in the cities, generally.
However, it's all about balance isn't it. Spend too long in the CBD's of the World and one day you wake up to find that you're out of touch with reality and grow weaker. Conversely, choose to suck a Hayseed from day one and that's about as far as it goes... I think that these are both called 'missing the boat'. Life's about decisions isn't it...
So personally, when I'm ready for whatever reason to stop answering to people, then I'll swap my city and country realities but cities are for the young and that time is not forever. Who was it that said, "Everybody is somebody's slave"?
Just sayin'... :)
Psyfy
NB. Now, back to electronics and technology.