AliExpress experience?

On Thu, 08 Mar 2018 08:55:36 -0500
<snip>


It was in the 50's a week ago. Cold, snow again but just an inch or two the past few days. We'll keep passing it along to your way ;-)
This article just ran in the paper. Kind of interesting when you have a minute or two:
"Epic salvage effort saved 230 new Chryslers from U.P. shipwreck" (Nov 1926)
http://www.mlive.com/news/index.ssf/2018/03/how_epic_salvage_effort_saved.html
Don't think it would be handled quite the same way nowadays...
--
Leon Fisk
Grand Rapids MI/Zone 5b
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
wrote:

That's quite a story. I used to hunt snowshoe rabbits near Copper Harbor -- in January -- and I can imagine what that was like. Frozen Hell is what is was like. <g>
--
Ed Huntress

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
wrote:

Nope, not the same at all. Collectors would be heading the effort, out there saving all the priceless old '26es this time. ;)
--
Silence is more musical than any song.
-- Christina Rossetti
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Thu, 8 Mar 2018 08:16:06 -0500, "Jim Wilkins"

I do that, too. Wally World had them for a couple bucks a handful of years ago, so during the summer, I fill in-store and refill after the self-checkout.
Milk is extremely susceptible to early death without being kept at 40 or below, so I use them for all cold and frozen foods. In the winter, the truck is cool enough not to need it for the (5 minutes, 3.5mi) drive home.

Did I just hear a "yet?" at the end of that first sentence? Another storm is hammering Seattle right now, given the yellow features on the radar screen on Wunderground, the last one over ID right now.
We've had drippy rain all day, and there is a 45mph wind advisory up. The real rain will get here tomorrow, it appears.

Not bad at all.

Indeed. You don't want dueling PSes on your hands.
--
Silence is more musical than any song.
-- Christina Rossetti
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
wrote:

The intent is for them to cooperate, with the higher of the two outputs, PS or solar, charging the battery. The series diode keeps higher voltage from backfeeding into the 13.8V PS and solar controllers are built to accept battery voltage on their output when their input fails.
I tested the concept with an old taper charger to which I added a Variac to adjust the output, on a hazy day when the solar couldn't quite keep up. The soft voltage/current knee of the taper charger allowed the battery to drop more than the well regulated switcher does. Perhaps today will bring enough sun to test the circuit before more snow arrives.
The Alpicool freezer current appears to average a bit below 1 Amp, though the power meters I have now are sized for the 50A max of the APC1400 and don't measure low currents accurately. The blue meter like you have can be off by 0.2A. This is on order to hopefully make more accurate Amp-hour measurements on lower powered devices and small batteries such as Lithium 18650s. (Amazon.com product link shortened)
-jsw
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Fri, 9 Mar 2018 08:19:07 -0500, "Jim Wilkins"

How does this differ from the diodes attached to most solar panels nowadays? You chose the exact schottky voltage you wanted?

Got preps? Somebody turned the storm cycle back on. Prolly that nasty AGWK stuff, which means OMIGODWEREALLGONNADIE!

Added to my list. This is one of the few times that Amazon ($18.56) vendors beat Ebay vendors ($23.35). The extra precision is needed for the little guys, I see.
--
Silence is more musical than any song.
-- Christina Rossetti
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
wrote:

https://www.allaboutcircuits.com/textbook/semiconductors/chpt-3/diode-switching-circuits/
Figure (d) shows a diode switch that passes the higher of battery or power supply voltage to the load while isolating them from each other. The diode in series with the lower voltage source is reverse biased.
I have the battery directly connected to the load and use diodes to select the higher of power supply or solar controller voltage. The power supply provides 13.5V through its diode, the solar controller limits itself at 13.9V if there's enough sun. The solar controller's series diode is internal, to keep battery voltage out of the panels and wiring. That diode shorted in my HF controller.
On a partly cloudy day like today the solar controller supplies whatever current the panels can produce and the power supply provides the rest of the load's demand. I can watch the power supply's input wattage rise and fall on a Kill-A-Watt as the sun dims and brightens. Sometimes the KAW Watt display goes to 0.0 and the system is purely solar powered, although the power supply is still connected and turned on.
When neither the solar panels nor the grid can provide power it reverts to the battery, all automatically.
-jsw
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Fri, 9 Mar 2018 14:25:59 -0500, "Jim Wilkins"

Good explanation, and I grok it now. Thank you.
--
Silence is more musical than any song.
-- Christina Rossetti
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
wrote:

The DC compressors are German. Just search for "Gleichstrom-Verdichter".
http://files.danfoss.com/TechnicalInfo/Dila/06/bd_compressors_04-2007_pk100c802.pdf
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Wed, 28 Feb 2018 15:35:45 -0500, "Jim Wilkins"

Cool. I saw a used (probably abused) unit on Ebay for $200 with $50 shipping, and new ones in the $500+ range. LOL
--
Shake off all the fears of servile prejudices, under which weak minds
are servilely crouched. Fix reason firmly in her seat, and call on her
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
wrote:

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
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Tuesday, February 20, 2018 at 9:36:18 AM UTC-5, Jim Wilkins wrote:

I have bought a number of small things from vendors on AliExpress. Usually anything you find on Ebay will also be available via Alli at a lower price . Not always true, but generally so. Have two things coming now. One is a flashlight, and the other is some security screwdriver bits.
Dan
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Tuesday, 20 February 2018 09:36:18 UTC-5, Jim Wilkins wrote:

sor-Portable-Fridge-Freezer-Chest-Solar-Panel-Fridge-Solar-Powered-Fridge/3 241043_32842967793.html

I have bought a couple hundred things through Ali. Been ripped off a few ti mes, and gotten meh stuff a couple more, but mostly okay to great value if you can wait or are willing to shell out for courier + brokerage. Buying do mestically in China I have had even better experiences Ali sellers know wit h an international transaction it will be prohibitively expensive for you t o ship it back.
Also domestic shipping in China is super fast and cheap. The courier phones you when they are close and if you don't answer (in *very* rapid Chinese, of course) they don't attempt delivery.
I don't think I would buy that particular item on Ali- I would look for the same item shipped from a local-ish seller.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Tuesday, 20 February 2018 09:36:18 UTC-5, Jim Wilkins wrote:

I have bought a couple hundred things through Ali. Been ripped off a few times, and gotten meh stuff a couple more, but mostly okay to great value if you can wait or are willing to shell out for courier + brokerage. Buying domestically in China I have had even better experiences Ali sellers know with an international transaction it will be prohibitively expensive for you to ship it back.
Also domestic shipping in China is super fast and cheap. The courier phones you when they are close and if you don't answer (in *very* rapid Chinese, of course) they don't attempt delivery.
I don't think I would buy that particular item on Ali- I would look for the same item shipped from a local-ish seller. ========================= Thanks.
Amazon lists only the 15 and 20 liter Alpicool models. I made a foamcore model of the 20 liter one and have been experimenting with filling it with emptied frozen food boxes and storing it various places in the car and kitchen. It can hold 6 days of frozen breakfast, lunch and dinner, probably several more if I pack my home cooking in zipper bags.
Although I wouldn't mind having a larger unit that Ali offers I just ordered the C20, due March 1 or 2 with free shipping. That's pretty local-ish.
It won't automatically switch from AC to DC if the power fails like the $700 Whynter, but I should be able to run it from a battery with a float charger to get the same result. -jsw
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Polytechforum.com is a website by engineers for engineers. It is not affiliated with any of manufacturers or vendors discussed here. All logos and trade names are the property of their respective owners.