HF Solar Controller

[stephent]

Bought one of the HF solar panel deals yesterday--the 3 panel one.

Hooked it up and played a bit with it and shut it down and unhooked it completely from the batteries (pair of Trojan 105's) and solar panels at dusk.

This morning it wouldn't charge, so being the inquisitive type--and really curious--I took it apart.

IT"S NOT exactly a charge "controller". It's a dump load controller based on battery volts only.

It also has a "cute" circuit that I think is supposed to short the panels out (which is where my trouble seems to be while it's "supposed" to be charging).

Now, if it's turned on--that shorting gizmo is supposed to be OFF--it ain't.

And if panel voltage is on, and the battery is unconnected (or fully charged--I think?) and there's no load on the "LOAD" terminals--the "short" is supposed to be there--it IS--no matter if and how ya connect or unconnect stuff...or reguardless of battery voltage.

It's a cheap azzed thing--don't trust your batteries or anything to it!

Look at the following pictures---it HAS a blocking diode in it..

See the straight connection from the panel terminal to the battery terminal on the negative black wire?

See the red panel + wire going to the switch and if the switch is turned on, it goes through the diode and to the battery positive--that's a 3 or 5 amp switch max--that's a 1N5402 "blocking" diode, rated 3 amps MAX (I saw 3 plus a tad over amps yesterday at mid-day). Don't parallel two sets of panels through one controller!

And yeah--I cut it all to $%%$## on the wiring, took all the little 9v and 6v (78XX regulators) out--took out the shorting FET--took out the load FET from the circuit completely.

This is just a pilot/trial setup and I'm ordering a MUCH better controller like right now!

It "would" work as specified IF you had a load stuck into the little phone plugs that would help keep the voltage down going to the batteries--but if it's sized to small--your batteries will cook.

Just a small warning on these --I suppose they are the latest versions out ??--so-called controllers.

Old adage of "ya get what ya pay for" holds true.

But the FET's are nice and large 45 amps or so each, and there's a nice chassis and indicating leds just waiting--I might just use it and put another PWM circuit onboard and actually make it into something useful afterall.

[ghurd]

Anybody but me figure 'Never trust a BIG shiny box without much stuff in it'?

It's not normaly called a dump load controller.  

Usually called a shunt controller. They normally shunt, or dump, the panel power through the FET.

Did it come with a booklet listing the circuit hystersis?  I'd like the numbers if it did.  Our stores don't carry PVs over 5W, or I'd look myself.

The battery surface charge might be high enough where the thing is not supposed to turn on yet.  Crazy waste of sunlight.

I like series controllers better.

Dare I play my broken record again?  SG-4 or SS-10. PWM, temp comp, very low Vf, cheap, no crazy beeper, etc.

Big Fun!

G-

[Bruce S]

stephent;

  Thanks for the heads up on this. Finally got enough of the "other wish list" caught up to get mine mounted in their "at this moment it times spot ;--)"

 I had a feeling that these wouldn't be much better than a car battery charger if that good, but since I have several Large SLAs hanging around sucking in all the juice these puppies will give. That it would be safe enough to let'em come up the voltage.

I thought it kinda pretty that I could plug those two CFLs in and they would come right on and light up ;--) .

Of course I had to pay homage to the solar fairy by quickly downing 1/2 a bud light so the clouds would go away.:--)

Found it interesting that I got brighter lights when I connected even nearly dead battery than when only the panels where lighting up the CFLs.

I have two cheap digital meters in place to monitor the volatge and current so now I'll keeep even a closer watch

Many thanks for the warning. BTW does your scream when you disconnect the battery and try to reconnect it without truning the charging switch off?

I plan on making use of the box as housing for one of coamanda's circuits.

Will use the other out put connetions for just that. Will be good to have a spot to charge the cell phones and not have wall warts hanging around just waiting for me to forget to turn them off.

Cheers.

Bruce S

[stephent]

ghurd...

the "literature" says when the level of the battery falls below 11 volts the charger/controller automatically shuts off the power output (output/load plugins) for over discharge protection.

Over charge is disconnect at 14.5 volts. The battery is not disconnected, the panels are shorted, and as far as I can tell with a short (punny--no?) look, or even a "long" look, the controller boards dc voltage is shorted at the same time as well--nice design. This thing could oscillate itself to death--off--on--off--on, etc at a rapid rate, and must have.

The circuit board is missing a few components here and there according to the layout silkscreen on the top. Seems to be a rehash of an old board....maybe to make it cheaper.

Didn't even figure on using it for any "controller" for the panels. It was just a temporary hookup for a day or two. New toy to play with, etc..you know.

Only point I wanted to make was that it really doesn't control much--just shuts off the juice with a shorting FET across the panel lines, and manages to cut it's own throat at the same time.

This one really "shorted" the panel lines--they are (were) staying that way.

Haven't tested the FET's yet..but they are rated nicely.

They are MTP50N06 type FET's. Both "should" be ok, they're rated high enough.

Did test the 3 amp blocking diode--it's ok, very surprising since it's just a 3 amp diode. 1N5402 type.

I need a dump load controller type anyway, well bigger then 1 1/2 amp load--that's the fuse size to protect the 780X voltage regulators for the "output" plugs.

I'll look at the SS-10, or maybe a bit bigger. Or just rebuild this chassis/box the right way (even easier then waiting a few days for the mail and less $$ since I have a ton of the stuff to do it with already). I'm already waiting for my "kill-a-watt" meter rather impatiently--it's been a whole 2 days now since I ordered it..hi--hi.

Bruce S---yeah it squealed, until it just quit working and then it "innnqked"--just one time each switch on--that's the sound it made when I turned it on, disconnected the battery or anything, and it managed to keep the shorting FET on with 2.75 volts from the panels and short out it's own dc voltage too--nice.

I pretty well gutted the wiring and circuit board from the "controller", but left the straight through connection for panel to battery--it ain't going to overcharge much of anything at 3 amps I hook to it.

But for the price of the panels and a couple of CFL's--ain't so bad a price even without much of a "controller" thrown in.

[coldspot]

ghurd-

"I like series controllers better.

Dare I play my broken record again?  SG-4 or SS-10. PWM, temp comp, very low Vf, cheap, no crazy beeper, etc."

Please tell us more

or

point to a link to the whole story!

Thanks

[ghurd]

Well, it seems from what I see, series controllers tend to be better designed and built.

Sandia did a bunch of testing a few years ago that showed series worked better.

The Morningstar products have 'stuff' others charge extra for, or don't even offer an option for in like priced devices.  

ie: temp comp in a $25 PWM controller?  SG-4.

I 'fixed' a lot of those 3x15W systems. Just changed the controller.

The little yellow ICP 7A controller is so bad the owners thought the system didn't even work, but it was working exactly as it was designed to.  And it would have been worse in winter.

"Night and day" one guy said.

I try not to directly bad mouth a specific product, but junk is junk.  In some cases it seems like a lie NOT to do it.

Ya-Da Ya-Da, Ya-Da... I sell the stuff. I can sell anything I want, and I want to sell good stuff.

I don't want to waste time and gas going back for free.

Remember, I have not seen this box thing some kits come with, like above.

I just have a feeling...

G-

[ghurd]

One Sandia report combines a lot of others.  There is a 76 page pdf link in this link.

http://www.morningstarcorp.com/products/SunSaver/