Producing power at night?

[Rabrsniver]

I have 4 Sharp 165 watt panels wired as 48 volts (they are 24 volt panels)

My system is 24 volts. I have them wired through an Outback MX60. Although there isn't much sun around here yet, I still get some usable power from them.

Last night I went out to the generator shed at 9pm, just to see what was what.

I looked at the readout on the MX60, and it showed that 40 watts were being produced. It was a pitch black night with no moon or other artificial light.

Am I crazy? What explanation is there for this? These Sharp panels have a blocking diode built in, so where is this power coming from, or going to?

John

[fungus]

Just a thought:

Could you try disconnecting the cable from the solar panels to isolate them from the system and then checking the reading? That would show if it was to do with the panels or the controller ..

[jnh]

My MX-60's LCD readout once became "stuck" like this (software revision 5.11).  It was a few days after I'd completely disabled the periodic 1.5-hour restarts, to cut down on relay clicking, and hasn't happened against since I re-enabled the auto-restarts.  There also was another charge controller connected in parallel on the MX-60's PV side at the time, which might have been a factor in getting it into a confused state.

If you see this again, try selecting Misc --> Restart from the front panel.

[DamonHD]

You may need to beat off the over-unity folks with a big stick too!  B^>

[ghurd]

Did you buy SOLAR panels or LUNAR panels?

I could not help myself.  At least I waited until you had good answers.

G-

[TomW]

I was going to say stick them back in the box in the attic so they are safe and hook em up. I couldn't help it either.

I suspect its the stuck display mentioned but if not its a helluva sales pitch for the manufacturer.

TomW

[fcfcfc]

Hi: The government has been doing random 900nm energy beaming from the international space station at night on Mon, Wed and Fri sense 1/1/2008. The money came from a private corporation but was funneled through the DOE for this particular testing series. It has something to do with extra molecular excitation in Viagra users... Your solar panels must have picked up on the energy beams and got excited....

[boB]

This is most likely from a temperature dependent offset drift in the MX60s

current-shunt amplifier.  It thinks there is still current.

One thing that the auto-restart thing does is to re-calibrate that offset.

There are other ways to do that, but I don't think that OB has implemented them.

If it thought the current had gone below the .2Amp to 1 Amp threshold, it would

have gone to sleep.  Is it hot in the room that the MX60 is in ?

How old or what firmware version is that MX you've got ?

boB

K7IQ

[electronbaby]

Ive noticed small erroneous voltage readings at night but never current at night. Im running 3 MX's. All seem to be pretty reliable controllers...after I calibrate the voltages lol. I just got a hub so that might fix it. The only thing Ive noticed is they lose voltage calibration when run hot. This screws up the charging algorithm. Things return to normal when they cool.

[elvin1949]

Tom

 Maybe they like starlight.

later

Elvin

[Rabrsniver]

Hi All,

I WISH these were "nighttime" panels!! (I knew I'd get a little ribbing about this)

I know its not possible - just relaying what the MX60 is telling me.

I forgot to mention that I saw this one other time, but that was a couple of weeks ago.

And after that it worked fine until last night. And today its working fine again.

Is it "resetting" itself upon wakeup?

bOB,

Its a very recent software version. Nevin has helped me with it. (I'm sure you remember him) It was a warranty exchange.

John

[Ungrounded Lightning Rod]

I'd say "check for radiation".  But if you've got enough fallout sitting on your panels to generate 40 watts you won't have to worry about it after a month or so.  B-)

[boB]

>>bOB,

>>Its a very recent software version. Nevin has helped me with it. (I'm sure you >>remember him) It was a warranty exchange.

>>John

Yes, of course I remember Nevin.

The temperature dependent current amplifier is still the same, so same problem I'm pretty sure.  Auto-start will fix this problem.  One of the last things I did was

to make that circuit a bit less dependent but it's not perfect.  Software can

help though.  I'll have to leave that up to them for now though.

boB

[Shadow]

You didn't run your wires through a current bush by chance did you?

[icicle]

maybe try turning off the night light.

[spinningmagnets]

Your system is obviously defective, but...

Since I am such a nice guy, I would be willing to take it off your hands! (if not, you might consider attaching magnets to it made from "unobtainium" and selling plans on the internet)

"I'll gladly pay you Tuesday, for a hamburger today!" -Wimpy (from the Popeye comic)