AliExpress experience?

I picked the SLI31MDCs for economical backup use, as I don't consider daily cycling to be practical here. I have to move the 100W Grape panels several times a day to dodge tree shadows, even in winter, and that's acceptable only for tests or during outages. We had another close call with icing yesterday, light freezing drizzle.

That was at a company I don't think I've named here, that didn't make consumer products. The batteries had sophisticated management systems and were well designed to be very reliable, and mostly they were. I don't remember seeing any problems with Segway batteries other than old age and have no experience with Tesla.

I've never seen a Lithium reach the 17 year life of my truck's battery, though I have some laptop packs that came close. I'm still using about half of the Ray-O-Vac Renewal rechargeable alkalines I bought in the 1990s.

Some Xantrex inverters have a load sense function that idles them to reduce battery drain when they aren't needed, like late at night when the fridge is off and there are no other loads. I needed a larger freezer compartment more than a second pure sine inverter.

"The datasheet shows 14.4W (about 1.2A) no load current, but this is in the "load sense" mode, which doesn't provide any power for things like the microwave clock, and other very small loads. In order for these things to work, "load sense" needs to be turned off. With "load sense" turned off, this inverter draws more like 60W (5A) with no, or little load."

That's worse than the APC1400's no-load 40W.

-jsw

OK.

I was amazed at my ten years on the Tundra battery, so you should be in awe of the 17 years. The battery, charging system, and user were all in sync, a very unusual occurrence.

Probably some sort of sleep mode for the CPU, eh? Nice.

I hear that. When I upgrade from the 2kw HF mod sine, it could be to one of these Taiwanese jobs:

5kva 4000w 48V

230v Solar inverter off grid 80A MPPT solar LCD remote controller. and add at least 3kw more panels.

Or, when I'm rich and famous, hang a couple Powerwalls on 10kw of panels and call it good.

They mention the drawbacks of inverters, and in addition to LED bulbs of all shapes, I've been buying a few 12v items, like soldering iron, coffee cup immersion heaters, massive 160w car heaters ;), etc. Here are some others I'm finding:

hot water kettle BB switch Still laughing at the last one.

A bit. You could buy a stable of panels and batteries for the price Xantrex wants for their stuff, too.

As batteries age they may require more than the normal vehicle charging voltage.

I turn up my LM350 charger until the current reads 0.5 - 1 Amp, being careful not to go too high and damage any electronics. Usually 15V is enough for a road vehicle battery that still has enough capacity to start, the U1R in my garden tractor which gets less use sometimes needs 17V.

After removing the vent caps I put clear packaging tape over the openings to control acid spatter. I can still see the electrolyte level and how much they are bubbling, or if one weak cell isn't when all the others are.

When the current falls below 1% of the Amp-hour capacity at >=14.0V I consider the charging complete. Those numbers vary somewhat among manufacturers.

I've been given "dead" batteries that an automatic charger could no longer charge, but which recovered well and lasted several years when charged once at higher voltage. They weren't completely cured, they still needed a somewhat higher charging voltage each time, and monthly attention to prevent or recover from the high resistance condition called sulfation.

I think this forced current, voltage-adaptive charging is the secret to long battery life.

I run a generator when I need a lot of power for a short time, like at meals. If not for the fridge's AC motor and 12A starting surge I could live with a 300W MSW inverter. The genny has a folding doghouse made from fireproof acoustic ceiling panels to quiet it and support corrugated roofing panels in wet weather. I should probably upgrade it to a more hurricane- and blizzard-proof model.

-jsw

Here is a good explanation:

" Eventually, the sulfate will cause a resistance to charge and a "false high voltage" reading will occur. The "false high voltage" is measured by the charge controller, which further lowers the charging current to maintain the voltage set point. This further increases the undercharge condition."

"6. Once the specific gravity begins to rise, the bank voltage will most likely drop, or the charging current will increase."

I've seen this on a battery that required 17V to initially force 50mA of current. As the battery recovered and its voltage fell below 15V the current rose to the limit of the LM350. It didn't harm my circuit but it needs to be considered.

-jsw

That's bad. Did your bank issue you a new card? Mind did after someone bought $1,200 worth of stuff one morning from a place called Fifi's Boutique, and I own no pets. I burst out laughing when the security guy called me and told me the name. 2 fresh cards after apparent fraud in 45 years isn't too bad. The bank had my money back in my account by the end of the same day, no problems. I go through PayPal/Ebay most of the time and have had no problems in thousands of purchases over about 15 years.

Accept? Are you selling, too?

The DC compressors are German. Just search for "Gleichstrom-Verdichter".

The better solar controllers have both an auto and manually programmed EQ switch. What bothers me is that the default with the switch on auto is 2hrs of EQ every 2 days. Seems a bit too frequent, doesn't it? That's from the Midnite Classic 150. 96A (@12v), 150v max PV, MPPT, 12-72v battery bank.

Low and slow amperage. No reason to upgrade to an LM338?

Good tip.

How often do you check it?

Interesting. (Saving this post.)

It's amazing how much sound comes from the engine itself, rather than from the exhaust, and baffles reduce both significantly.

Indeed. Maybe go subterranean in a hillside with drain and a flat roof to muffle sound and defeat wind/snow?

I set my P20L solar controller to limit at the float voltage and never equalize. If the house batteries need it I'll take them outdoors and use a variable voltage charger. SLI31s are the largest batteries I can carry up and down stairs with one hand, the other free for the handrail or doorknob.

I think the order of LM338s I received was counterfeit. The limiting item is the 30V/3A current meter, which has much better voltage and current resolution than the 30V/10A model. I also use an LM317 that limits at 1.5A, and that is enough for the 105A-h SLI31s and everything smaller.

A battery could be left on that topping-off setting for days because the current is low.

Fiberglass pipe insulation over the muffler outlet barely changed the sound. The acoustic tile box should be enough to conceal it from thieves driving by. I can't hear it from the street if a car is within

1/4 mile.

I have a rock drill and a hillside in the right place, but not a blasting licence to cut in to it. This year's summer project is digging some exploratory holes and trenches.

-jsw

The compressor draws about 30W, 2.2A at 14VDC. With the compressor off the controls use less than 1W.

I cooled it to -20C and then connected a DC power meter and ran it 61 minutes (to shutoff), using 1.172 Amp-hours at 13.8V, or 16.1 Watt-hours, in my 56F basement. At that rate a 12V 105A-h battery should last 2-3 days.

The cold plate is behind one wall of the food compartment, without a circulating fan. I'll have to experiment to find the right packing arrangement and temperature setting for frozen food. -20C is its lowest.

-jsw

Cool. I saw a used (probably abused) unit on Ebay for $200 with $50 shipping, and new ones in the $500+ range. LOL

Could weight be considered a negative in the LA chart of features?

So the cheap Chinese semiconductors are no good, or what? Why did you think they were counterfit? Low output? I haven't had the lid off my bench supply, a 0-30v, 0-5A current- limiting Chinese model, but I wonder what chip they use.

When you say "slow charge", you mean it, don't you?

"float"?

Yabbut, the bad guys have impeccable hearing and sense of smell.

Oh, boo! That could have been =fun=.

Only if I can't carry it upstairs. They rarely move.

The printing matched Internet warnings, and one burned out too easily. The vendor refunded my money without any argument.

Replacing a month's self discharge doesn't take long. I can charge at

25A if necessary, or borrow a neighbor's 50A wheeled charger.

A somwhat higher voltage. Most charger setting recommendations only specify voltage. Inexpensive Volt+Amp meters like this now make current monitoring practical, so I use parameters from battery data sheets that include current values for charger designers. They allow higher voltage if the current and/or charging time is limited.

Other people' generators are louder.

I've never owned a chest-type freezer before and have to learn how to use it, like how much air space to leave, when/how to defrost and not letting things get stuck. I do have a Fluke thermocouple meter to measure temperatures around the compartment.

-jsw

I bought some LM317s from China a while back. I'll go look for warnings on them, too.

That only means yours will be the last to be stolen. Criminals are nothing if not persistent when they sense a gold mine. They work so hard to avoid work, I swear.

That's good. I read that Danfoss catalog and was impressed at how much info they crammed in there. Wow!

When I read "isobutane", I was fascinated and had to find out what other refrigerants they were using now. R600 is nButane and R290 is propane, used by two of the compressors they make. ASHRAE refrigerant properties link within first message here: or

This is what I'm doing with home-made metered voltage regulators that operate from solar panels.

The LM350 and a 33.00V / 3.000A meter are a good match. The meter reads to my LM350's 4.5A limit, at least briefly. (Short URL; there are other vendors)

Including the car they are in.

There are enough unstealable generators on concrete pads to blanket the area with omnidirectional engine noise. I think I can run mine for an hour or two at meal times and use the batteries between and overnight. That plan is based on bad weather more than theft risk. In good weather my 300W of solar panels may be enough.

A KAW on the Alpicool C20 predicts it using 0.4 KWH per day, for $2.20 a month as a -18C .freezer.

It ran 2:00 hours on a Whistler 'Mighty' Lithium jumpstarter that I can use for grocery shopping trips, on the deep cycle low battery voltage cutoff setting. The car battery setting cuts off at a higher voltage so the car will still be able to start.

I think the compressor may be a copy, it has an Alpicool label and the schematic is different. The blue metal-cased wattmeter recorded peak startup currents around 4~5A.

So far I'm happy with it as long as it doesn't break. The car has a

12V outlet in the back and tie-down eyes.to keep cargo from sliding, which the motor cover grills might not stand up to very well. The cover was dinged when I received it. The C20 seems more suited to the 'burbs than the boonies.

-jsw

The driver may let off the thieves, and I have seen non-running, unlit cars drive past my house at night in the past. Pop the trash bag in the garbage can and then hear tire noise drifting by. Hmmm...

Yeah, that's good.

Not bad at all, but that's a pretty tiny box, only 0.7 c/f.

That's the pits. When I buy family packs of meat, I always try to bag each item separately and freeze them so they don't stick together. Otherwise, it =all= has to thaw to separate them.

Pray for good cooler/comp lifetime. Running watts w/ w/o comp?

Bad packing or bad handling before boxing? G'luck with it.

That it is, which is why I asked about using AliExpress to order a larger version than Amazon offers, and made a model to experiment with. I think the 6-7 days of food it holds plus the same in the fridge is enough. Time will tell.

Now that this one has run a while the evaporator tubes show as two lines of frost all the way around near the upper edge, so they do cool all four walls, and it's resting on the insulating foamcore footprint template from my model of it. I happened to have a wire grid the right size to raise the food slightly off the bottom and let cold air underneath.

The area of the bottom is about twice that of a Coleman Oscar. I was satisfied with them for long trips because they fit in the rear passenger footwells where they are within reach without stopping. One needs ice, the other has a thermoelectric "cooler" lid. The C20 will freeze ice packs for the Oscar.

Thanks, I'll try that.

I bought the small fridge second-hand in the 1980's so its doom could be near.

30-35W in Eco mode,

Yup.

Good deal with the grid. If there were a flaw in the insulation, a piece of meat resting on the bottom could rot at that point and not be noticed until it was too late. I'd love to tour the plant where those are made.

There ya go.

Knock on wood.

That's amazingly little power draw. How cool will it run on Eco with the t-stat low?

I had noticed that food on the bottom of my 28F fridge wasn't quite frozen, so I bought a 2-for-$1 pack of wire racks and folded one to cover the bottom, with bubble wrap sandwiched inside. The thin

30-gauge thermocouple is very informative.

My Sprint 3G and 4G are down today and this dialup is too slow to find the photos I saw earlier of the Foshan Alpicool factory.

The loud squeaking when it started and stopped turned out to be from the electric skillet on top of it.

The lowest setting is -20C. I set it at -18C, the Euro standard, which is 0F. The thermocouple reads 5F ~ 10F at various places. It cycles on for 2-1/2 minutes, off for 5-1/2, at 60F room temperature. This summer I'll find out how well it likes roasting in a hot car, if it lasts that long.

My oldest, weakest SLI31 is powering it right now, recharged from the

100W roof array.

This morning I took it grocery shopping, powered by a Lithium jumpstarter in the shopping cart and the rear 12V outlet in the car. Five days of breakfast, lunch and supper fit in snugly. It's light and narrow enough to carry with one arm so I can open doors with the other.

-jsw

Sprint problems: