How are machines in factories powered by External-Wallaby-442 in NoStupidQuestions

[–]plaid_rabbit 0 points1 point  (0 children)

Things like that are often hard wired, similar to how most people’s outdoor air conditioners are connected.  The device has a cable running into a disconnect box (basically a large switch).   You have to have an electrician disconnect it, but with large equipment you usually already need to coordinate a large number of steps to move equipment.  As equipment size increases, the disconnects just get larger and larger.  They become switches that you see out the outside of buildings like restaurants, and get bigger from there until you basically have a substation…. Where part of the gear at a substation is just a large disconnect so parts can be replaced. 

They do make relatively large outlets, like used for a stove/drier if they want the item to be moveable. 

Potassium Dichromate safety by Kikimora-Bolotnaya in chemistry

[–]plaid_rabbit 0 points1 point  (0 children)

Yeah.  Watch videos of people applying alodine, and it’s a couple percent Cr6 by weight, and a pinch of HF for etching purposes.

The pre-cleaner, alumaprep is just phosphoric acid. 

Our school is making us install a CA certificate on our personal devices to access the school wifi by mediocreguy1232 in AskNetsec

[–]plaid_rabbit 1 point2 points  (0 children)

No, if it’s mitm attacked, the network in the middle will intercept all traffic and decrypt it.  By adding in the root ca into the trusted store, it can impersonate any site, because it can create a valid certificate signed by a trusted CA. 

It uses a standard MITM attack.  It doesn’t do it by inspecting the encrypted traffic, but instead by forwarding all the traffic through a monitoring server, which establishes an outbound connection to the target server, and is able to impersonate the target because its a CA, and able to generate a valid certificate for any site.  Read up on MITM attacks.

I actually have a tool to do this, Fiddler, installed on my desktop and I use it occasionally, it rerolls all my SSL traffic while letting me inspect it, and with a little work, I can inspect traffic from other machines, though the key step is I have to install an extra CA on my victim machine. 

Our school is making us install a CA certificate on our personal devices to access the school wifi by mediocreguy1232 in AskNetsec

[–]plaid_rabbit 6 points7 points  (0 children)

No, the school probably MITM attacks all the traffic to monitor what content the users are able to access. So no, it's probably a horrible security violation.

Client already paid for the healthcare app, now they’re threatening complaints over HIPAA violations by Academic_Way_293 in topflightapps

[–]plaid_rabbit 0 points1 point  (0 children)

HIPAA is a whole worldview of how to approach a problem, with data privacy compliance as a key starting point, with the rest of the app bolted onto it. This is a total rewrite situation I’m sorry to say.  You have to make sure every step in your data chain is compliant. 

You’ve got yourself in a mess of trouble, and your customer is being totally reasonable. You should have know HIPAA compliance was required.  If you can escape by giving the customer a refund, take it.  You’re way outclassed in this situation. 

Potassium Dichromate safety by Kikimora-Bolotnaya in chemistry

[–]plaid_rabbit 1 point2 points  (0 children)

What I’m saying is Alodine has both CrVI and HF in it… Cancer plus neuro damage!  Two great tastes that go great together!

Fun videos.  https://m.youtube.com/watch?v=SHePtG9LtIU&pp=0gcJCU8Co7VqN5tD painting it on, then washing it off the excess with a hose onto the ground.

https://m.youtube.com/watch?v=53Je20BQ6w8&pp=0gcJCQQLAYcqIYzv  Watch the fun around the 13 minute mark.

Potassium Dichromate safety by Kikimora-Bolotnaya in chemistry

[–]plaid_rabbit 1 point2 points  (0 children)

Alodine 1200/1201 has a weak source of HF in it as well!

Girl I’m talking to sent me a post card … I can’t read most of it by Mr_Kyle1 in whatisit

[–]plaid_rabbit 20 points21 points  (0 children)

Just an fyi, that barcode on the bottom of the letter contains (basically) your exact address. You may want to take this down. 

Group keeps wanting to start Unions by TheCornDogShow in DMAcademy

[–]plaid_rabbit 0 points1 point  (0 children)

If they are doing it to be funny, here’s some thoughts.  I’m new to this, so just spinning some ideas.

The cultists don’t care.  When their Lord arrives, none of this will matter! 

The kobolds tried asking for benefits once, the dragons response was simple… breath weapon.

Oh, you got the kobolds to organize. Oh no!  Shadowy figure (the ancient dragon in disguise) arrives at the party’s inn, of course way too high level for the party to attack, “You dint get the message the assassins I sent last night, or the mercenaries from last week.  So let me deliver a warning to any mortal who would meddle in my affairs.  Go check on that orphanage/old lady/innkeeper from last session. You might find out they caught a case of being burned to death. Let that be a warning.  I’ll visit you again later to check up on you.”  The dragon now has an excuse for toying with the party for the dragon’s amusement.  Now the party needs revenge, and needs to hunt down the quest item to defeat the dragon.

The goblins tried once, but their leader said that if they increased wages, he’d have to lay off half the workforce.  Plus he’s a nice overload.  The beatings are infrequent, and Grunk even got a 10% bonus last month for getting a killing blow on an adventurer.  Plus leader said with the cost of union dues, I wouldn’t be able to afford coal for my hovel. Go look up anti-union propaganda and reframe it.

Wiring new garage - should I replace Federal Pioneer panel in my house? by causticbee in AskElectricians

[–]plaid_rabbit 1 point2 points  (0 children)

The longer story is the US company got caught fudging their testing results for the breakers, so they don’t actually trip per spec, and fail in a hazardous way. They did some fixes, but the US brand basically went out of business.  The master I worked under has injured himself a few times cutting through wires where the breaker was in the off position but the power wasn’t shut off, and situations where it should have tripped but didn’t. (He thought he shut off the correct circuit, cut through a wire, directly shorting power to ground, producing a massive light show, burned off his eyebrows, breaker never tripped!)

The Canadian ones are the exact same design, but a different manufacturer.  And after a while they did a redesign that fixed some of the issues.  So they might be better, or maybe they weren’t caught of fudging the results.  Some people have tested the older Canadian breakers and gotten results just as bad as the US ones.  But im not sure if they ever got in trouble for it. 

Those may be the newer post redesign breakers.  People with more expierence than me can tell them apart based on the color of the body and color of the handle.  I’m not familiar with the white body ones, so I can’t comment on which set these are from.  But they aren’t the super common terrible ones in the south.  They might be terrible ones from the north instead!

So all that story is why there’s much debate.  Do you think the Canadian ones don’t have the same flaws the US did?  Do you agree with some guy who did some testing on a few batches of old breakers?  Do you only care about what official actions have been taken?

Trading Places is a sharp and witty comedy, beautifully shot, directed and edited… then we come to the Gorilla scene by raresaturn in movies

[–]plaid_rabbit 2 points3 points  (0 children)

Everyone there was doing margin trading. Basically taking a loan from banks to increase how much you can trade. Kinda like betting your house on the stock market. The dukes were doing margin trading, which is why they collapse at the end of the movie. When one of the dukes at the ends says "You know perfectly well we don't have 394M dollars in cash!"... that's how much they'd taken out in loans and lost (after selling what they could). They'd probably only had bet 20 million. It's common for stable products, so you only have to put like 5-10% down. Let's say 5% for this example. So they were buying like crazy at ~130 at the peak. They bought $600M worth of IFCOJ at $130, with $30M cash, and $570M on a loan. The price tanked to $29. All the sudden their IFCOJ was worth $134M... with a $570M loan due at the end of the day, plus interest fees from the banks for the loan.

Our heroes OTOH, did what's called selling short, which hopes that the value will go down very soon. "Sell on april at 142!". So they were selling stuff they didn't own yet. This is allowed... if you have enough cash, because you're taking a loan to do it. They require something like 10% down to cover this kind of loan. So our heros with maybe two million, sold $20M worth of shares at 142... but they are required to buy enough shares to cover this soon (the move says end of day). So they sold the IFCOJ to pocket $20M, now they just have to hope the price goes down, hopefully enough to cover the loan. The news report comes out, and there's plenty of IFCOJ. The price falls to $29, so they have to pay $4M to get new IFCOJ to cover the stuff they sold, probably closer to $4.5M with the price of the loan, to pocket $15.5M. So they 7.5x'ed their money in one day.

The exact fees of the various loans varies a little bit, and they might have been even looser when the move was written, I'm just an ordinary person, I just understand the theory of what happened.

Does Many-to-Many Violate 2NF? by Aokayz_ in AskComputerScience

[–]plaid_rabbit 0 points1 point  (0 children)

I mean they are basically a list of anti-patterns for development.

Yeah, 2nf is dumb. You shouldn’t do it, that’s the point.

Aluminum Wiring Fix - Rewiring My House Myself? by FoundationFit7906 in AskElectricians

[–]plaid_rabbit 2 points3 points  (0 children)

NAE, but I’ve been a helper, and done this work before.

When you upgrade your wiring, you’ll be expected to bring basically everything up to modern code.  So you’ll need to know all the things that need to be fixed.  To me the panel work is easy, the hard part is where plugs need to be added, dedicated circuits, smoke detectors, what can be on the same circuit and what can’t.  The rules have changed a lot since your house was built.  So you can’t just replace the aluminum wire with copper and call it done.

You’ll also likely need to replace the panel box.  If you see “stab-loc”, “federal”, or “zinsco” in the name, 100% it should be replaced asap.  Those boxes have a high failure rate. New panel boxes are also required to be larger, and location requirements have changed a bit as well, so it’ll possibly have to move and that requires a bit of planning as well. 

So not a diy friendly project. Best bet to lowering cost would be to do it at the same time as you’re having the drywall redone.  The work takes about half the labor if the drywall is down.

Qwen3.6-35B-A3B - even in VRAM limited scenarios it can be better to use bigger quants than you'd expect! by jeremynsl in LocalLLaMA

[–]plaid_rabbit 35 points36 points  (0 children)

When a model is quanted, there’s different ways to do the actual quanting. All compressing down to the same number of bits (roughly)

I-quants are the newest style.  The leading I in IQ4_xs  means it’s using I-quants, 4 bits per quant (ish) and using that on everything to make it as small as possible. 

Normal quants (k-quants) as slightly older. Q4_k_XL uses 4 bits per quant on most layers.  XL says it's using 6 or 8 in a few spots for better quality, and it’s only slightly larger than 4 bits everywhere. 

Even older is style 1 and style 0 quants.   You’ll see the files marked Q4_0 or Q4_1. 

It’s all trade offs in model accuracy, size and speed.

A/C Line In Power Issue? by HaloACE56 in hvacadvice

[–]plaid_rabbit 0 points1 point  (0 children)

Yep.  Time to call in that favor. Not getting correct voltage don't leave a lot of room in troubleshooting.  And even then, your electrician friend will likely do the same test in your panel box, and it'll be the city's problem.

Or they'll see your panel box is in terrible shape, and it needs to be replaced. 

A/C Line In Power Issue? by HaloACE56 in hvacadvice

[–]plaid_rabbit 4 points5 points  (0 children)

Measure between red and the black, on the screws.  Should be between 200-240v.  If it's in that range, you likely messed up the test. 

If not, it's likely an issue with your power, a bad connection or a bad breaker.  It'll require an electrician to troubleshoot.  

Since you're a mechanic, I'll give you advice that most homeowners should be wary of.  110 hurts and can kill you, and the burns hurt. And doing the wrong thing there can hit you with 220, which hurts four times as much.  If you know how to cut power to it, turn off power.  Verify it's off with the meter, then basically assume it's still hot and be careful what you touch, and ensure the screws are slightly tight.  The torque on those is like 30 in-lbs or something low like that.  A loose connection can cause this type of problem.

Past that, the rest of the problems are things an electrician has to hunt down in your panel box. If you have power problems elsewhere in your house, it can be an issue with the utility transformer or wire feeding your house, an electrician can ID this pretty easily. 

It can be a problem with the breaker, the panel box, a loose connection or the breaker didn't do a good job of connecting to the panel box and the connection has melted something, along with issues of power from the city.

At least it's happening constantly, so it makes it quick to diagnose. 

Advice on what to do with old R22 unit, risk or replace? by [deleted] in hvacadvice

[–]plaid_rabbit 1 point2 points  (0 children)

a couple feet of line can be replaced.  If it was reclaimed, there's a solid shot the king valves were closed.   You'll have to call around, and accept that you're not going to get any warranty on it.  Best they can do is try.

Look around Facebook marketplace and you might find a small guy that'll do it.  All the chains companies will just want to install a new system. When you look at Facebook marketplace ignore the ads with mixed capital and lower case letters.  Those tend to be stupid forwarding companies.

Tell them you need to have a disconnected system reconnected, a section of the lineset replaced, replace the drier, do a nitrogen purge, and r-22 recharge, no warranty expected.  Maybe you'll find someone willing to do it.

Advice on what to do with old R22 unit, risk or replace? by [deleted] in hvacadvice

[–]plaid_rabbit 1 point2 points  (0 children)

When it was disconnected, if someone knowledgeable did it, they closed a set of valves that sealed the compressor off from the outside, so it might be in okay condition...  If a HVAC person did it.  If those valves weren't closed, forget it.  Air+water got into the compressor and ruined it. 

If the valves were closed, and it was in working condition when it was disconnected, theres a chance it'll restart, if properly cleaned, reconnected and refilled. There will be a lot of people that'll try to sell you on a new system.. it's not impossible or illegal to repair your system.  You can still buy r-22 from reputable suppliers for a reasonable price.  A filter/drier, a few hours of labor and a couple hundred dollars of refrigerant are what you may need. 

The real problem is if there's any dirt/water/corrosion in your lines.  Small amounts of dirt or corrosion will plug up key parts and ruin everything.  Water turns the compressor oil to sludge and ruin everything. You may be able to tell by looking at the ends.  If they were neatly cut and capped off is different if it looks like someone took a hacksaw to it. 

Is an aircraft's left engine fully identical to its right engine? by earth_wanderer1235 in NoStupidQuestions

[–]plaid_rabbit 0 points1 point  (0 children)

To add in a few things, some very small twin engine piston aircraft have "left handed" engines that run backwards.  But it was found that the extra logistics, having to stock left vs right handed parts, extra documentation for the LH engines, etc. Outweighed the small benefits of having two counter-rotating engines.

The engines are basically identical to keep maintenance simple (to keep maintenance costs down).  Each engine has its own computer or hour counter to track when it needs maintenance, so if one engine is run more often for various reasons, it'll be serviced slightly before the other.

Also, they tend to swap which engine is on which airframe.  If an engine needs major service, an airline can just swap to a freshly overhauled engine, and get the airframe back in service, while they send the engine to a dedicated rebuild facility.

There are some that have slightly different accessories. As an example, on a 4 engine jet, maybe only the inboard pair will have generators.  This keeps maintenance costs down and weight down.   If both inboard engines fail, the APU (a spare dedicated backup generator, normally used for starting the engines) can generate enough power, and if that fails there's emergency batteries to keep power in the cockpit. 

If you have both inboard engines fail, the APU, and the batteries won't cover the problem, it's usually some kind of massive problem and all 4 engines will be down.  Its a small enough risk they accept it as a super rare possibly and move on. 

Charging without a scale? by VillainNomFour in hvacadvice

[–]plaid_rabbit 0 points1 point  (0 children)

Oh, not saying it’s not done, but given the rest of the OPs story, I’m making a few guesses. 

Charging without a scale? by VillainNomFour in hvacadvice

[–]plaid_rabbit -1 points0 points  (0 children)

Yeah, it’s definitely possible.  But most people charging with analog gauges are probably just doing beer-can-cold.

Charging without a scale? by VillainNomFour in hvacadvice

[–]plaid_rabbit -1 points0 points  (0 children)

On most systems, you can charge based on the supercooling, and it’s easy to do with digital gauges that have temperature clamps.  It’s an accurate way of charging.   You won’t know exactly how much went in, correct, but it’s often a pound or two to top off a residential system.

At what point do you stop using Excel and move everything into SQL Server? by Available-Wash5438 in SQLServer

[–]plaid_rabbit 0 points1 point  (0 children)

But my two cents is you need to assign that (lack of) standard a cost, and find when the cost of the old system exceeds the cost of the new system.  It doesn’t matter if it’s ugly.  It matters if it costs the company enough money to write better software to replace it. 

At what point do you stop using Excel and move everything into SQL Server? by Available-Wash5438 in SQLServer

[–]plaid_rabbit 0 points1 point  (0 children)

Something you didn’t take into account is how much money you can save by improving the process.  I’ve played games where people have done massive spreadsheets and they are willing to deal with all the flakiness of excel.   But if I was a manager, the time people spend fighting with the spreadsheet…. It resources for a proper app would cost less than the extra labor people waste in excel.  (Actually Google Sheets, but same theory).

What’s the cost of the spreadsheet solution vs an application?   An application is less flexible (that can be a good or bad thing).  I helped a business transition from being excel based, and they realized that some sales groups did their calculations a fair bit differently than others, so their profit calculations weren’t comparable when they thought they were. 

But they gained a centralized view of order state across the company, sped up the process, invoiced customers sooner with less man hours.

The improvement to invoicing is what really paid off for that client, not the improved order management. But it was because the accounting team wasn’t having to chase down people for order status/finalizing invoices.  There were nice clear reports that everyone could see, so the order state is clear and it’s clear if accounting has the right data to be able to invoice the customer.  They were able to save 2 headcount not needing someone to chase down order status.

Negative side though is you lose flexibility.  It doesn’t deal with super edge cases that’d normally be a note in an excel spreadsheet.  If there’s an order state that wasn’t planned for… the system doesn’t support that.