Charge controller suggestions for 45w Harbor Freight kit

[(unknown)]

My father-in-law has a hunting cabin and wanted to experiment with solar power so I turned him on to the Harbor Freight 45w kit.

He's had the kit setup for about a month with a wal-mart deep-cycle battery and an 800w inverter to run a few 120v 15w CF's, a radio, tv and occasionally a microwave.

He's had some problems with this setup so last weekend I went up and took a few casual readings.  It looks like he's getting 22v off the array with full sun and his battery seemed to be fully charged (~13v).  However after spooling up some load and such the "charge controller" never seemed to kick into "charge" mode and I'm suspicious as to if it is working or not.

After doing some research here and elsewhere, I get the impression that the included controller is all but useless.  I'm considering picking up a replacement for him (partly because I feel responsible for recommending the kit) and after some reading I'm considering the Steca Solsum 8.8:

http://store.altenergystore.com/Charge-Controllers/Solar-Charge-Controllers/Pwm-Type-Solar-Charge-Co



ntollers/Steca-Solar-Charge-ControllersPwm-Type/Steca-Solsum88-8A-1224V-Charge-Controller/p1539/

The price seems right and the ratings appear to allow for some expansion (he's considered picking up a second kit) but I'm pretty new to all this and I thought I'd get some opinions from these boards before pulling the trigger.

Jason

Moved to the proper section

[iamdewayne]

Hi Jason,

Did you 'load' the battery long enough to drop the voltage far enough to get the controller to switch?

Something must be working for the battery to be at 13 volts.

I'd get rid of those cfl's. Go to Lowes or the home depot and get some 12 volt flourescent tube lights instead. Your battery will last longer. Same with the radio and tv, go to 12 volt.

Every time you convert your energy source, you lose effeciency ( and load time )

Your losing 1/3 of your panels power to begin with, so use what you have left wisely.

If the system stays at the cabin charging all week and works good the first day but not nearly as well the second day, add another battery. A week is plenty of time to get a second battery charged and the two will not fall off as much.

Read this:( hint, right click the link and choose open in new tab or window so you keep this page and dont have to keep hitting the back button) http://www.solar-electric.com/charge_controls/mppt.htm

The first half of that explains why you are losing 1/3 of you panels output to begin with.

Ya gotta keep father-in-laws happy!!!

Luck, Dewayne

[DamonHD]

Note that there are 12V CFLs: I have a nice one for my desk!

Rgds

Damon

[WindChopper]

Which version of the HF Controller is involved?

OLD: Gray tin can with LEDs.

NEW: Alum housing with Digital meter.

Just curious.

I have used both Morningstar SG-4 (3 panels / 1 HF kit ) and am currently using a Morningstar SS-10 ( 6 panels / 2 HF kits on tracking mount ).   Got both Morningstars from ghurd and think that they are nice controllers.  

Looked at the specs on the one you mentioned, and it looks like it is 12V & 24V compatible ( Or is it just too early in the morning ? ).

Agree with the above comments .... get as much off the 120v inverter as possible and run native 12 vdc loads to loose the conversion losses.

[iamdewayne]

Hi again Jason,

Almost forgot...  Is the battery a true deep cycle?

If the specs on the battery list CCA ( cold cranking amps ) it's not the right battery for storage.

Golf cart batteries work well as they are true deep cycle.

[(unknown)]

Thank you for the infoe Dewane,

I was able to measure a voltage drop at the battery after running everything other than the microwave for about 15 minutes.  After that I saw a .1 drop from my original reading.

I read through the page you posted and that definately makes sense, but I'm not sure how I can remedy this; are you saying that I should be looking for a charge controller that provides MPPT instead of the one I posted?

[(unknown)]

This kit came with the "old" controller; a tan box with some jacks in the front and some LED's that are supposed to indicate voltage (of what I'm not sure).  They stayed at their maximum (15v?) the whole time I was there so I'm not sure what they indicate.

What's the average price on the Morningstars?  

Also when the controller says it's 12 & 24v compatible, I assume that is the battery voltage but is that incorrect?

[(unknown)]

One other note, the system seems to be working but I believe that he took the battery home a week or so ago and charged it, so that voltage I saw on the battery could be left over from that possibly.

[(unknown)]

I believe the battery is a true deep cycle, but I didn't purchase it and I wasn't able to get alot of information off the battery.  I was expecting it to be rated in amp-hours but the only rating I could find was something like "260 minutes @ 8 amps" (I'm sure that's not correct, I didn't write it down) but the capacity was expressed in minutes and an amperage that I assume refers to the typical draw from a trolling motor or something?

(for the record I recommended an Optima; )

[AbyssUnderground]

Thats probably the reserve rating. Most are something like 25A for 90 minutes. That would equate to about 75Ah but its still not a proper rating.

[tecker]

Chuck it and get more batteries at 75 to 80 watts you'll never get close with five or six 180 Ah batteries charge 3 one day then 3 the next . If not topped of run them again. The Joke here is that you don't have to do anything but hook every thing up and start using power.You have to work with a system to get the most out of it .

[(unknown)]

By "it" do you mean the charge controller?

I guess the bottom line is,  will the controller I posted originally work as an improvement over the stock controller, and leave room for a little expansion?

[WindChopper]

"I guess the bottom line is,  will the controller I posted originally work as an improvement over the stock controller, and leave room for a little expansion?"

1. By my experience, yes you do need to replace the controller.
   
2. The particular controller you asked about, I cannot speak for.   But it looks ok from what I can see from the spec sheet.
   
3. The asking price is about half way between what I paid for my SG-4 ( 4.5 amp ) and my SS-10 ( 10 amp ) so that looks ok.
   
   

HF tried to get too cute with LEDs that mean nothing and their power distribution stuff.   Get a decent controller with decent batteries and you should be happy with the return on your investment.

I consider the HF kit a reasonable "Bang for the Buck" purchase even with the "old" garbage controller and intend to expand my array out to 9 panels in the Spring.   The "new" controller may even turn out to be more reliable and negate the need to replace.

Hope these comments help.

Russ

[ghurd]

Bottom line- probably anything would be an improvement over the HF box.

I don't have any direct experience with the new 'big tin box' type HF controllers, but the track record for every previous controller they ever put in the kit is below poor.

I see some things I don't care for in the Steca controller.

First, it is a shunt controller. I believe series is far superior (so do most Sandia papers I have read).  I don't think a shunt controller can give the battery much of the benefits of PWM, other than a stable voltage.  They still seem to brag about it anyway by calling it "Fast and Gentile".

The "Schottky diode" is nice for home-made, but kind of outdated for a fancy factory made unit. It will have about a 1/2 volt drop by itself, where better controllers often have a total voltage drop of 0.1V and sometimes less.

"Cycle Charging" and "Boost Charging"?  I don't understand what that even is intended to imply.

"Mosfet Switch" and "equipped with an integrated circuit" is like bragging you have an analog cell phone.

If it is "Electronically short circuit protected", why does it need the "Built-in fuse"?

I would still go with a SG-4 with one kit, and a SS-10 ($9 more than the Steca) for 2 or 3 kits.

No.  I didn't have enough coffee yet.

G-

[tecker]

Just spend the money on batteries two more batteries on that three panel setup will never overcharge  and you can switch in the controller when your gone to enshure that they stay up.

[tecker]

  In order to get a battery to charge you have to take over the load that's in circuit including the charge load . With less than 3 amps to work with your locked in to charge or discharge .

[quidnon]

Hi All!

I have a similar "clone" of this kit - from Northern. Got 4 (15W) panels and one (used) 20W Solarex.  I bought the 7A "Sunforce" controller:

http://www.northerntool.com/webapp/wcs/stores/servlet/category_6970_770399+6228?cm_ven=PPC&cm_ca
t=I-search%20(Google%20Adwords)&cm_pla=nt_alternativeenergy&cm_ite=sunforce%20charge%20controller

So far, the system is working - I'm thinking of adding a 1000W inverter for small AC loads.

I'm thinking of spending the bucks to upgrade the controller to the Morningstar MPPT to "squeak out" any extra amps possible:

http://store.solar-electric.com/sbchco2512vm.html

Think this is a waste of money??

btw...

system is 12V w/ 2x 110Ah marine deep cycle batts. Using a Trimetric 2020 meter for moniotring.

Thanks for the time and comments!

Wayne

[ghurd]

For your system- It is a complete waste of money!

It can, sometimes, increase the output about 20%. Sometimes.

About $25 more for a HF 45W kit will increase the output over 50%. Always.

And it comes with those neat 12V CFLs.

I used some of those MPPTs you linked to, but the next step up (the iX).  Great so far.

They are made by Blue Sky, not MorningStar.

G-

[quidnon]

Thanks!

Good to hear some solid advice and save me $.  Sorry for the 2nd post in the controller section - was not sure if anyone would see this.

[Bruce S]

Jason;

   Since I have been using the same controller for over a year now, I thought I would weigh in here.

First, the LEDs on the side of the controller is the voltage levels available coming to your loads. The 15V light being on all the time basically means that your panels are in enough sun light that it's getting that voltage level to the battery)ies) and the screaming speaker is about to kick in.

This little unit is OK for what is does and it's cost as a "starter kit". I still use mine, but with a slightly different idea. I use mine as a PDU, power distrubtion unit. AND for that it works perfect. HOWEVER, some of the units have been found to have a major soldering problem.

Open the top and look straight down at where the 3,6,9 VDC plugs are at. Look amd make perfectly sure the Diodes are NOT grounding to the metal box. This problem short the battery charging system so the only amount of charge you'll see going is less than 3 V.

Second do what Ghurd says, he talking real life knowledge here, take a look at the SGx units, go with the larger unit if you do intend on growing the system. I have the SG4 and it works without fail.

The outpout of the SGx can then be connected to the PDU and you'll have a nice system that is very functional a stable.

Also one other item that I have found to be VERY usefull because I have ordered and installed 7 already, it Ghurd's dump controller, if you put this gem in place just after the SGx unit it will dump any excess power to whatever you want it to, and will keep that nasty horrible screaming speaker thingy from sounding off, OR stuff an Q-tip into the speaker

As for the current battery:

I see no reason to "chuck" a good battery. If you are getting this system to be usefull and stable, this battery is perfect for doing just that, no need to WASTE anything.

If you need it, I can take a picture of my SG4 so you can see how I put it together for easy ADD-On of more panels, once I can afford them:-)

Hope this helps;

Bruce S

[Bruce S]

tecker,

I'm missing the point you'e trying to make?

Surely you're not saying the chuck to system and start again or chuck the battery?

NOT cool .

Jason has stated that the system works, OK for now and is wanting to make sure it stays that way.

He gave way more than enough info the show that, even the battery is working out, father-in-law knows that just in case, he's taking the battery home and giving it a charge.

Smart thinking in both cases.

The system is very similar to the one I've been using for a year now ( okay since last November) and I've statified with it's performance for the price.

Please explain what your thinking.

Bruce S

[tecker]

A three amp charger will never top off three batteries in one days charging . So while in use in a 24 hour cycle your going to get the Max charge with the Batts connected to the solar front end directly the controller can be switched in when away to keep the batts maintained . A different controller is a waste of money and three batteries will be hot and ready to go on the next visit.

[ghurd]

I don't see where the 3 battery part came from, or why it would be necessary / desired / required to top them off in one day (even if I don't believe it's possible in a reasonably balanced and regulated solar RE system).

I don't see how 3 batteries will be 'hot' with a 3A solar, let alone how 4 or 5 PAIRS of T-105s could be maintained.  (from the "5 or 6 180AH batteries" thing)

I don't see how "three batteries will be hot and ready to go on the next visit", if someone has to baby sit and change batteries.  Especially if they are not 'visiting'.

Best possible scenario is 1 battery ready, right?

I don't see how $50 for a decent controller is a "waste of money", compared to $600 minimum (for cheapest route I see given your spec's) in extra batteries that will be wasted in non-use.

[tecker]

 My point is ... a controller with that charge load expectations  is a battery killer . A controller  uses  several hundred milliamp s operating and won't bring the single battery back up from a heavy discharge in 6 to 8 hrs so chuck it and get several batteries instead .Granted three or six batts won't work on a 2 to 3 amp 6 hr charge either but if they make it to the 12.3 range you can just about mix and match your loads to work out    I think the battery he's talking  about is a marine battery .So two more of those  can be had for around $130 . He's got unreal expectations for load ,lights radio or TV an inverter and microwave  from a 60 ah battery . Shopping for a controller to improve the performance of this panel combination is good money after bad .There's a lot one can do with several batteries that will almost work for a few days there and several days away . Charge them on the way there and use the vehicle as main charge source. Add  some other charger in there or the like . You can probably count on the controller to maintain some batts and they'll be in the 12.5 to 12.8 volt range in 4 or five days Not hot but acceptable .You just don't need regulation for a 3 amp  6 to 8 hr  charge  on a 25 %down 60 ah battery and adding a few more will inshure that you won't overcharge should you be called away for some reason .

[ghurd]

Now I understand what you're thinking, even if I don't agree with it.

The SG-4 uses 6ma.  The SS-10 uses between 6 and 10ma.

Even my little dump kit only uses 4~8ma.

The Steca claims 4ma max, and it looks like it has 2 LEDs (must not be very bright!).

[tecker]

 The panels will give a better charge connected directly to the battery or batteries

is what I should have said and left it at that . I stopped tring to use the amorphous panels to current load my bank some time ago . They do a great job at filling up capacitors to give a 17 to 19 volt pulse every second even on a low light day .I've had 7 amorphous panels up for a couple of years with them dedicated to a dump pulser works great starts early and finishes late .I used straight regulation , current limiting and a Battery Minder . They just don't post any sort of charge until aproching midday . Would be better tracking but still direct connection with two seperate banks  ,switching the charge every two hours worked the best in a current configuration.

[ZooT]

I often wondered about whether or not a charge controller uses some of the charge itself, and I guess I know now :-)

I'm using a xantrex C-35 in dump controller mode, and wonder what that uses.

On topic, I decided when I read all that nasties about the HF controller, to bite the bulet and buy the C-35.....and it has "plenty" of room to grow with my system.

[tecker]

Batteries have a tendency to Cap up ( my term for that rise in voltage as the plates have a localized charge that hasn't distributed to the surrounding electrolyte). The controllers I 've had hooked up adjust to that and some internal shunting goes on . Ie the current is sometimes half of what is possible with direct connection .That being said a patch around the controller for the first 2 hrs of charge is a good idea to get the dipole established in the battery. When the battery is in discharge ions are attracted to the plates and push trough the screen to get to the plate .Ie the ability to get high current .When in reverse (Charge mode) the ions pass slowly through the screen  and and go through several impedance levels    as the  SG builds in the main body of electrolyte .  For those reasons  the I believe control is best used as a battery maintainer after a full charge dipole is present in the battery. More coffee please.    

[(unknown)]

First off let me say thanks to all of you for providing tons of information to consider when working with the HF system.

For now I've decided to go with the controller that I posted about initally and experiment.  I think for this system, it's application and it's location that it's a good starting point and inexpensive enough that if we outgrow it I won't sweat replacing it too much.

It sounds like we could improve our system alot by taking a few more steps in addition to replacing the controller.  New wiring is in order as well as replacing as many 120VAC appliances as possible.  For the most part this should be easy but I'm not sure about the microwave (I'm not sure it's really a necissity anyway).

It also sounds like we could benefit from some re-wiring with the proper guage cables and reduced run lengths.  One question I have on this front is whether or not there is a downside to using standard ROMEX solid-core type household wiring or if the more flexible, stranded cable is superior.  Obviously when you get larger than 12 gauge the solid core stuff is harder to work with, but is there a performance advantage of one over the other?

Thanks again for all your help and I will update this post after hunting season with the results of the new controller and any other changes we can fit in.

Jason

[ghurd]

I like the romex.  Finding suitable boxes, connectors, etc is easy.  Probably not a very good idea if the wire will be subject to 'wiggling'.

If it will be out side, or exposed to sunlight, use the UF type.

G-

[brkwind2]

Why worry about all this?  I never claimed to be a mathematician but it looks to me like the payback for these solar panels is about 100 years.  They will be long dead before that & considering the energy required to make them you have a net loss.  Fine if you like to tinker but don't think your "green" by doing so.  Probably just the opposite.  Haveing said that I'm considering buying a set for backup power for the T.V..  When the power is out & the wife is watching tv & not bossing me around then they are worth any cost.

[DamonHD]

The energy (not financial) payback for solar PV is getting better, typically under 2 years if actually taken out of the box and used well I think!

Thin-film is about the most energy-efficient to make and pays back soonest.

Rgds

Damon

[(unknown)]

Does anybody have first-hand experience with the newer, aluminum cased digital meter controller? I just bought a couple of the 45w kits that came with the newer controller and while I love how it thoughtfully provides so many outputs from 3v - 12v in monoplug form plus a CLA and even a USB power port, everything I've read about the previous versions makes me dubious about its innards. The manual doesn't mention blocking diodes and advises you to disconnect it from the batteries when you're not actively charging them.

I don't mind buying a better charge controller, but I'd really like to know something about just how good or poor these units are since I have them in hand and I'm still up in the air as to just how much expandability I'd want if I bought another controller. Also, the nicer controllers mostly don't offer much in the way of custom outputs.