Blue Sky 2000E let me down

[stuartbell]

I just installed a new Norcold refrigerator on my Gemini - powered by 195 watts of solar, a Blue Sky 2000E, and 200 Ah of AGM batteries.

After several unattended days of clowds, the voltage in the battery bank dropped below that required to run the Norcold. I expected the unit to turn off - but it didn't - the draw continued with no cold produced until the battery went to zero volts.

I'm trying to find a regulator to shut off the refrigerator when the voltage drops (see other post).

The Blue Sky 2000E solar controller made a minor problem much worse. The unit draws its operating power from the battery side of the controller. When the refrigerator discharged the battery bank, the unit shut down. When the bright sun returned, the unit did not restart - thus allowing the good PV power to just "fall on the floor."

This left me with a 0 volt battery bank, a useless set of photo cells, and no real way to get it going. I eventually jump started the solar controller and the system restarted, nearly recovering after 3 days of bright sunlight.

This is a very serious defect in the Blue Sky 2000E. Had the load been a bilge pump rather than a refrigerator, the boat would have been lost - even after the storm ended and the sunlight returned. Just as the USCG requires marine alternators to be self-excited, I expected the Blue Sky solar controller to restart when solar power was present - and to work as hard as it could to recover my battery bank.

I've had several e/mail exchanges with Richard Cullen of Blue Sky and he insists the unit is working as designed - I insist it is designed poorly and unsuitable for marine use.

My current plan is to take part of my solar panel "bank" and remove it from the solar controller - leaving it connected to the battery bank through a diode at all times. Hopefully, if this problem ever recurrs, the single solar cell will provide enough power to start the solar controller and then rechange the bank.

The Blue Sky 2000E is probably typical of solar controllers - and it does work the same as the other controllers in teh Blue Sky line -- all unacceptable for marine use in my opinion.

[Freesail99]

Seems to me that a 200 ah battery bank is on the small side to run a refrigerator in the first place. There has to be another draw on the batteries. The 195 watt solar panels should be more then enough to keep the battery bank charged.

[GeorgeB]

Sorry to hear of your problems. My experience has been solar panels (I have the flexible kind) rarely, if ever, live up to their advertised wattage. Perhaps it’s the high latitudes of Northern California (38 degrees, ha!) or the atmospheric conditions, but I get nowhere near the advertised wattage. My Adler Barbour cyles about half time during the summer so I expect to run through about 60Ah every 24 hours. My solar cells almost never put that amount back to the grid. You may experience more power consumption if you are in a hotter or more humid area and most likely experience less power generation (after-all it never rains in sunny California). I have a SunSaver controller from MorningStar which has a low voltage disconnect feature so when the battery state drops below 11.5 volts, the refrigerator (in your case) could be disconnected from your grid. The electronics in your controller probably operate at no less than 11 volts so I’m not sure wiring a solar cell directly to the battery would work (as in the case your battery drops below 11v in the middle of the night.) The downside to the SunSaver is the refrigerator would need to be wired directly to the load side of the controller which, in my case, would by pass my Link battery monitor/controller. I know of other owners who have wired their reefers to an isolated battery and run solar to that as a way of keeping a run-away reefer from chewing up their house bank.

[Maine Sail]

Sorry to hear that! The charge controller, in my opinion, should self start!


On another note 200ah bank and only 195 watts of panel is WAY, WAY, WAY undersized for refrigeration 24/7... As others have said NEVER believe the panel manufacturers and their "ideal situation" based specs...

If you don't have one get a good battery monitor such as a Xantrex XBM..

[camaraderie]

Originally Posted by Freesail99

Seems to me that a 200 ah battery bank is on the small side to run a refrigerator in the first place. There has to be another draw on the batteries. The 195 watt solar panels should be more then enough to keep the battery bank charged.

Free...agree on point #1....disagree that 195 watts of panels will keep things charged. That will generally provide 50 amp/hrs average...which is less than most refrigeration will need without anything else on the boat being on.

[sailingdog]

A lot of this is dependent on which Norcold refrigerator the OP has installed.

The 7.0 cubic foot model draws 3.2 amps per hour according to one site's specifications. BTW, that sounds like a very low power draw for a 7.0 cubic foot refrigerator, given that the Engel 27 refrigerator I have supposedly draws 3.1 amps, and is much smaller and probably more efficient. That is about 80 amp-hours per day.

However, a 200 amp-hour battery bank is a bit on the small side... and 195 watts of solar panels are only going to provide 50-55 amp-hours of power on a sunny day, less on a cloudy day, on average.

What the OP needed was something like a BatteryBrain Marine III. The device is designed to prevent something from running the batteries completely flat.

[Maine Sail]

Let's not forget that a 200ah bank really has only 100ah of usable discharge before you hit 50%. Dischraging regularly bellow 50% will severly shortent the life expectancy of the bank..

The fridge alone, at 3.2 amps, is drawing 76.8 amps per day or 76.8% of your total usable capacity of 100ah's.

You're using roughly 25 amp hours more, every day, than your panels can even keep up with in full sun!!

It's not a surprise that your bank went to zero. Even with a 400 amp hour bank you will eventually be at zero. You need a bigger solar array or a passion for warm beer...

[camaraderie]

....an you can bet that 3.2 amp spec is IF you keep the lid shut!

[sailingdog]

he wasn't aboard, so likely the refrigerator wasn't opening and closing itself....

Originally Posted by camaraderie

....an you can bet that 3.2 amp spec is IF you keep the lid shut!

[chucklesR]

Stu runs a Norcold DE-0061R on his 1993 Gemini, Shearwater. The 200ah bank is light, but then it's a catamaran where light is good. I personally run with almost 300ah and don't use 12v for the fridge.

I'd call him one of our most knowledgeable owners on the yahoo group.
I personally prefer my propane powered Dometric over battery refridgeration, but he did gain 3 cubic feet of space and a larger capacity for ice making.

Stu, I'd blame both the Norcold and the Blue Sky, both should have low voltage shut downs.
One way to fix both is a battery combiner, any one of which has cutoffs for low voltage.