We know this comment by Shannon Martin is correct and sensible because it was reviewed by Shannon Martin! As a licensed insurance agent, I’m sure she is qualified to talk about uh… electronics… hmm
This was the first result on Google
Submitted 8 months ago by glibg10b@lemmy.ml to technology@lemmy.world
https://lemmy.ml/pictrs/image/1abf9bc1-3995-4c96-a9a9-9d595949b005.jpeg
Comments
Worx@lemmynsfw.com 8 months ago
frezik@midwest.social 8 months ago
This is the sort of person who thinks you need to ground yourself to be safe while working with electricity. Not 100% wrong, but just wrong enough to be very, very dangerous.
Transporter_Room_3@startrek.website 8 months ago
Some people know just enough to be dangerous.
For instance, an anecdote:
A nearby local hardware store put up a sign in 2017 and now this year, in front of the welding equipment, that says “WELDING GOGGLES DO NOT PROTECT EYES AGAINST THE SUN”
Now if they didn’t block uv from the sun, then they wouldn’t block uv from your welding arc.
BUT I 100% stand by their choice to put the sign up.
Because you need a certain shade or darker, and they sell a lot of different shades for different welding applications, including the safety tints people might want if they’re nearby and catch the occasional reflection.
And some people know enough to know welding arc = UV, sun = uv, and don’t stop to think about intensity.
In fact, in 2017, I knew someone who tried to use a #3 lense to look at the total eclipse, and as soon as the moon cleared moved enough for the sun to peek back, he deeply regretted not using a darker shade. Now has a weird spot in his vision that isn’t quite right.
nilloc@discuss.tchncs.de 8 months ago
Just ground your left hand while you work on it with your right hand. That way if it’s live it’ll quickly stop your heart and you won’t even know you died. No half measures!
RobertoOberto@sh.itjust.works 8 months ago
Working with small ESD-sensitive electronics and using a proper grounding strap and mat with large resistors in series to provide protection from shock? Absolutely.
Wiring up a car battery or working with mains power? Absolutely not.
nonfuinoncuro@lemm.ee 8 months ago
worst ai prompt
MrEff@lemmy.world 8 months ago
Looking passed the absolutely insane answer here, no one has even brought up the whole issue of AC vs DC. Batteries are DC, while your fridge that plugs into your wall running on AC. I know they make DC ones, but it isn’t like they are interchangeable.
themeatbridge@lemmy.world 8 months ago
Funny thing, most modern refrigerators use DC motors for their compressors so that they can run at variable speeds, so there’s likely an inverter that you could bypass if you know the appropriate voltage. The DC ones for RVs are the same internals, just without the inverter.
nixcamic@lemmy.world 8 months ago
Correction: they still use AC motors, but those motors don’t use line AC. It goes line AC > rectifier > DC > inverter board > variable frequency AC to run the compressor motor.
DreadPotato@sopuli.xyz 8 months ago
Funny thing, most modern refrigerators use DC motors for their compressors so that they can run at variable speeds
No they don’t…they use AC motors and a VFD to control the speed.
Silentiea@lemm.ee 8 months ago
I mean it’s probably labeled, right? How hard could it be?
cantrips@lemmy.world 8 months ago
Shannon Martin says just shake the battery and you’ll get DC.
ironhydroxide@sh.itjust.works 8 months ago
Just swap the leads back and forth very fast
Scubus@sh.itjust.works 8 months ago
Just run the rectifier in reverse, duh
tfw_no_toiletpaper@feddit.de 8 months ago
There are DC-AC converters you can use (might be called inverters in English idk), which are pretty interesting circuits.
ColeSloth@discuss.tchncs.de 8 months ago
That part just takes an inverter.
I’m not sure of the max load output on a car battery, but with a 15 amp 1800 watt dc to ac inverter, you probably can run a fridge off one. It probably just won’t last all that long.
Naz@sh.itjust.works 8 months ago
Hello, expert solarpunk here.
**TLDR: Car battery is 350Wh. Fridge uses 143W idle, so it’ll run a fridge for 2-3 hours. **
Explanation below:
Car batteries are lead-acid (sulphuric acid and lead plates).
They discharge according to Peukert’s Law as the negatively charged plate gets covered in lead via the acid (electrolyte).
As the battery depletes, the negative plate can begin to take permanent damage, and so you can’t discharge a lead-acid deeper than 10-20%, or about 10.8V, with the safe limit being ~50% discharge.
Most 12V, 60Ah batteries therefore only safely store and nominally discharge 350 Wh @ 350W.
You can discharge that as fast as you want but the faster you discharge, the lower the capacity is (with 1000-1500W bringing you way down to like 65 Wh). Fridges have a surge when they start up to fire up the compressor. Starter batteries can take that, but once the refrigerant is cold, the fridge just maintains the temperature which uses a lot less energy - about 143W on average.
baru@lemmy.world 8 months ago
Fridge uses 143W idle
Isn’t that like 1250 kWh on an annual basis of idle usage? An efficient fridge should use 150-200 kWh per year, this isn’t just idle usage. Even an inefficient fridge would be really high with that kind of idle usage.
genie@lemmy.world 8 months ago
Also assumes that the average fridge runs on 12V 😂
EdibleFriend@lemmy.world 8 months ago
I don’t know… you didn’t mention your uncle once…
Seasoned_Greetings@lemm.ee 8 months ago
That’s because he is his uncle. You’re seeing the source material, be amazed
alilbee@lemmy.world 8 months ago
Wow, those are some serious Licensed Insurance Agent skills
Aux@lemmy.world 8 months ago
You have a very inefficient fridge! My fridge is rated for 272 kWh per annum, which is 745 Wh per day or 24 Wh per hour. You need to buy a new fridge.
drathvedro@lemm.ee 8 months ago
Fridge uses 143W idle
The only thing running in idle is the timer and power led, which consume insignificant amounts of power. By my calculations, the average modern fridge does bursts of ~300W during compression and defrosting cycles, with ~40-50W consumption on average over long periods.
HeckGazer@programming.dev 8 months ago
You did not answer their question. They asked for Watts, not Watt hours. Average car batteries have a CCA in the range of 500 to 1000 Amps at 12V, so you could reasonably have 12kW in there :D
magnolia_mayhem@lemmy.world 8 months ago
This reads just like an AI response
Krudler@lemmy.world 8 months ago
AI told me 76C/170F is ideal for hot tub water temperature.
Sure no problem. Once I get used to that I’ll work my way up to boiling peanut oil.
T156@lemmy.world 8 months ago
If nothing else, the tub would certainly be hot at that temperature.
Aux@lemmy.world 8 months ago
75°C is definitely ok for a hot tube for a short session.
postmateDumbass@lemmy.world 8 months ago
Regardless of source, if your refrigerator is running you better go catch it.
Its stealing your food.
TheControlled@lemmy.world 8 months ago
I was hoping for this old chestnut somewhere here
WhiskyTangoFoxtrot@lemmy.world 8 months ago
You keep chestnuts in your fridge?
vsis@feddit.cl 8 months ago
Hey, ChatGPT, my uncle says new Macbooks are just glorified Raspberry Pis.
How many MB/s are in a Raspberry Pi?
whotookkarl@lemmy.world 8 months ago
It will take some mathversion to convert from the CPUs/s a Mac uses and the MotherBoards/s in a raspberry pi. I’m working on getting some insurance for ChaGPT to find out.
RamblingPanda@lemmynsfw.com 8 months ago
About tree fiddy
Dehydrated@lemmy.world 8 months ago
Raspberry PIs don’t run on MB/s, they use GHz.
locuester@lemmy.zip 8 months ago
You just need to use a conversion. 1 MB/s = 9.66 GHz
nobleshift@lemmy.world 8 months ago
I’ve been living off-grid fulltime for 6 years now and that answer is completely and thoroughly wrong. Not just wrong but completely missing the fact you’ll need at a minimum a 2000w inverter.
You’ll get 2 hours of usage AT BEST from a car battery, and if it’s lead acid, Gel or AGM chances are you will irreversibly damage (even if just slightly) the battery if you let it run until dead dead.
LifePo4 FTW!
cmnybo@discuss.tchncs.de 8 months ago
A car battery shouldn’t be discharged at all. They are meant to supply a short burst of power and then be charged back up again.
A deep cycle lead acid battery can be used to run an inverter. They can be discharged to 50% capacity while still providing hundreds of cycles. If they are used for a backup and are not cycled frequently, they can be discharged to around 80%, but they will provide a lot less cycles.
A LiFePO4 battery is definitely the better choice for anything that needs to be cycled frequently though.
John_McMurray@lemmy.world 8 months ago
Just wire the inverter to your car battery and run the engine. Hard on gas compared to a 3500 watt generator, but you already have the car, inverters a few hundred bucks, and the genny would be at least 2500 dollars
abhibeckert@lemmy.world 8 months ago
Sure but in an emergency? They can handle it.
abhibeckert@lemmy.world 8 months ago
An inverter will not let you run your fridge until the battery is “dead”. It’s going to have a minimum voltage, likely somewhere around 11 Volts, which is plenty of charge to maintain the long term health of a lead acid battery.
nobleshift@lemmy.world 8 months ago
Easy big fella. I over generalized and I’ve been on the internet long enough to know that a fully contextualize and source siting answer is always called for. Also you’re explaining this to a guy who lives off of 400ah on a 29ft sailboat and hasn’t been to a dock or a slip in 5 years. I get it.
noobnarski@feddit.de 8 months ago
At 11V you are already damaging most lead acid batteries, especially starter batteries.
If you only do it a few times it will probably take it, but not much more than that.
Tbird83ii@lemmy.dbzer0.com 8 months ago
So if I turn the car battery upside down, a 12v DC battery should run a 120v AC appliance?? Brilliant! I have an idea for how we can use this with two fans to create infinite energy!
lemmyvore@feddit.nl 8 months ago
It will never beat my idea to strap a buttered piece of toast to a cat and make antigravity.
nixcamic@lemmy.world 8 months ago
I’ve also done the off grid thing and you can get way more than 2 hours on a car battery if the fridge is already cold and you aren’t constantly opening the door. Also have ran modem full sized fridges on 1000w inverters. So YMMV.
The_Tired_Horizon@lemmy.world 8 months ago
I run a fridge freezer off a Delta Pro and 600w of solar during the summer. If we get a few days spell of bad weather I have to place it back on mains. Its good to have in an emergency, though it cost me 3 months wages (plus overtime)
arandomthought@sh.itjust.works 8 months ago
Uh, watt?
LazaroFilm@lemmy.world 8 months ago
Volt
arandomthought@sh.itjust.works 8 months ago
Thank you for clarifying.
Gobbel2000@feddit.de 8 months ago
While reading the question I thought: “That’s not how Watts work”, but then this “answer” hit…
IndiBrony@lemmy.world 8 months ago
Now I don’t know enough about electronics to know how wrong this is, but I do know enough about electronics to know that this absolutely sounds wrong.
The problem comes when someone takes an answer like this, knowing far less than I do, and they try and hook up their fridge to a car battery.
And this is why I hate LLMs. Being confidently wrong is scary enough when it’s just people, nevermind technology.
It does make me chuckle, though, that Skynet could have been totally innocent in their destruction of the human race, they just confidently came to the wrong conclusion and had the tools to carry it out.
Like a toddler whose inner thoughts are telling him to throw a cat out of the window. He doesn’t know he’s going to kill it, he just knows that’s what his brain is telling him to do.
genie@lemmy.world 8 months ago
Now I don’t know enough about electronics to know how wrong this is
Very, assuming the refrigerator in question typically runs on a typical power grid you’d find in the US or Europe (source: am electrical engineer)
Mainly because most compressors I’m aware of use alternating current (AC) motors, or at a minimum accept AC power. Batteries alone produce direct current (DC). The simplest way to make this work would involve an inverter (converts DC to AC). Cheap ones probably have at least a 10% conversion loss, so you’re looking at an hour or two at most.
xantoxis@lemmy.world 8 months ago
From a technical stance, it’s right. This top comment does the math pretty well, and I’ve done it myself recently trying to decide if I should add a battery backup on my fridge. If you can overcome the startup surge (and a car battery definitely can), a modern fridge doesn’t draw very much power.
Of course, there’s a lot of details missing about how you do this without dying of electrocution. So I think it’s also a fair criticism of the LLM.
jayandp@sh.itjust.works 8 months ago
“Mr. President, we’ve come up with an ingenious way to automate our nuclear defenses.”
“Oh wow, how does it work?”
“We gave a toddler the nuclear football and told him to press the red button when pictures of the “baddies” appear on its screen.”
“You what?”
billwashere@lemmy.world 8 months ago
Jesus… the stupid, it hurts.
madcaesar@lemmy.world 8 months ago
Chat GTP answer
Sure, let’s say you have a typical car battery with a capacity of 60 amp-hours (Ah).
And let’s assume you have a small refrigerator that consumes about 100 watts of power when running.
To calculate how long the battery can power the refrigerator, we need to convert the power consumption from watts to amps.
Power (watts) = Voltage (volts) × Current (amps)
Assuming a car battery voltage of 12 volts:
100 watts / 12 volts = 8.33 amps
Now, we can determine the approximate runtime:
60 amp-hours / 8.33 amps ≈ 7.2 hours
So, with a fully charged 60 Ah car battery, you could run the refrigerator for approximately 7.2 hours before the battery is completely drained. However, it’s important to note that factors such as battery age, temperature, and other loads on the battery can affect actual performance.
mlg@lemmy.world 8 months ago
Licensed Insurance Agent
seems legit
Zink@programming.dev 8 months ago
That answer is like the electronics version of the image with Patrick Stewart and the caption:
“Use the force, Harry
-Gandalf”
schnokobaer@feddit.de 8 months ago
Licensed Insurance Agent
BilboBargains@lemmy.world 8 months ago
This post made me beat my head with a 2 by 4
lemann@lemmy.dbzer0.com 8 months ago
May be a better fit in !mildlyinfuriating@lemmy.world or similar
SoleInvictus@lemmy.world 8 months ago
I looked up the page and it gets worse.
You will need to shop for a car inverter. Find one that is at least 1,500 watts, and it will help you power your refrigerator for up to five hours—usually without damaging your car battery. Considering how much food we keep in our refrigerators, a $200 car inverter is a bargain!
ABCDE@lemmy.world 8 months ago
For the uneducated, what’s wrong with it?
Veneroso@lemmy.world 8 months ago
Licenced insurance agent. Not for long!
artvabas@lemmy.world 8 months ago
Accept the battery is DC 🔋and fridge runs on AC🔌
renrenPDX@lemmy.world 8 months ago
My chickens say Shannon is full of shit.
Dramaking37@lemmy.world 8 months ago
My buddy’s EV does this but without math or worrying sbout ac/dc except to pump it on the stereo that is also plugged in.
ramenshaman@lemmy.world 8 months ago
It hurts.
recapitated@lemmy.world 8 months ago
Sounds like a jippitty conversation.
Rentlar@lemmy.ca 8 months ago
This reads like a shitpost. The math is eh, okay, but the explanations are totally wrong. I won’t even try to figure out what “runs off watts” means.
Enough of any electricity source, using various converters can get any appliance working “technically speaking”, but in the end the amount of energy available at the source and the rate of consumption at the end and any intermediates. So “technically” an AA battery can power an industrial electric press, but only for a fraction of a microsecond, using a lot of charge storing infrastructure and with a lot of changes to get the tiny bit of DC into the machine requires to operate, likely 3 phase AC power.
A proper explanation would say a lead-acid car battery provides power at around 12V and electric camping fridges nominally operate around 12V so you can connect them directly and operate it (so you can sorta say they both run off DC volts?). If not you would need a buck or boost converter. The available energy of the battery (Watt-hours is a useful unit here) and the consumption rate (in Watts) of the fridge determine how long you can use it on the battery.
Alpha71@lemmy.world 8 months ago
classic example of being wrong with authority.
werefreeatlast@lemmy.world 8 months ago
I thought America runs on Dunkin… (doughnuts)
No easy conversation from doughnuts to volts or amps. I give up. But with enough oxygen you can hear up pretty gud with a single doughnut. Then you could use a Stirling engine to pump heat from the fridge to the environment. Energy in a doughnut ~224cal according to Wolfram alpha. That’s 940kJ. 940kJ/1hr~260watts which should run a fridge for 1 hr. However energy conversion is probably going to leave you with like 10% at most of usable energy so ~6 minutes run time. America needs a lot of doughnuts!
Encinos@dormi.zone 8 months ago
Remember the time Jeremy Clarkson fitted his car with a fridge in Africa and no one wanted to give him a jump? Yeah that.
bjoern_tantau@swg-empire.de 8 months ago
Image
LazaroFilm@lemmy.world 8 months ago
He looks shocked.
Hule@lemmy.world 8 months ago
Mehby
abcd@feddit.de 8 months ago
Safety is no 1 priority!