WC 1M Post Challenge - You Ready?!

Grabber5.0

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Jan 1, 2015
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Just to be clear.

There's nothing wrong with DC and majority of the complaints against it were marketing noise.

Today, they now use HVDC for long distance transmission. One because it's better than AC with losses, two it's generally safer because you don't get all the extra crap that comes with HVAC, such as magnetic resonance, skin effect and other wonderful things.

It's most likely that in the future all HV transmission will be DC.
Redemption LOL
 

N_LaRUE

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Apr 3, 2013
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Redemption LOL
In a way.

Not that I'm a fan of Edison. He was more businessman than scientist/inventor.

DC in general is more dangerous if you get electrocuted. You can't let go. Unlike AC. AC will typically throw you, DC doesn't.

Anything under 48VDC is considered safe.

In general though, it doesn't take much to kill as human with electricity.
 

Rose640

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Bring back memories of my working days. Actually I'm not surprised at the random formatting you found. In my old place of work where everyone that works with Office, 90% of people just stick to Excel for everything, from tables to reports to even memos & letters.

Uhm, what? Excel for memos and letters? What the actual f?
 

Rose640

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Just to be clear.

There's nothing wrong with DC and majority of the complaints against it were marketing noise.

Today, they now use HVDC for long distance transmission. One because it's better than AC with losses, two it's generally safer because you don't get all the extra crap that comes with HVAC, such as magnetic resonance, skin effect and other wonderful things.

It's most likely that in the future all HV transmission will be DC.

I lost 1 point on exam because our proffesor made the skin question totally not understandable.

There's also peak/RMS values with AC that makes it less attractive. But back then, it was all about being able to step up/step down the voltage, which wasn't easy to do at all with DC.

Also, magnetic resonance, did you mean the induced current in nearby lines?
 

Rose640

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How do DC transformers even work? Constant magnetic field won't induce current in the second coil.

There has to be semiconductors, I think.
 

Rose640

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How do DC transformers even work? Constant magnetic field won't induce current in the second coil.

There has to be semiconductors, I think.

With diodes, yes, to invert the singal, amplify as AC, rectify back to DC. But that's dumb.
 

N_LaRUE

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I lost 1 point on exam because our proffesor made the skin question totally not understandable.

There's also peak/RMS values with AC that makes it less attractive. But back then, it was all about being able to step up/step down the voltage, which wasn't easy to do at all with DC.

Also, magnetic resonance, did you mean the induced current in nearby lines?
Electromagnetic field is what I meant.

Been awhile...
 

MSFTisMIA

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Dec 20, 2012
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So I'm watching the great gnashing of teeth with the Oneplus 8/8 Pro and the Xioami Mi 10/10 Pro. Death of the flagship killer, they say.

In some sense, they are right.

Qualcomm's screwing everyone this year with the chips. And with how the market seems to be pushing people to buy stuff over $1000, I'm not surprised. Apparently, they're people willing to pay that price. I don't think from what I was seeing I'd upgrade from the Mi 9 to a Mi 10. I think they're some people who don't want to spend no money to get some high end stuff. Nothing ain't free like that.
 
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raycpl

Active member
Apr 6, 2013
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Didn't expect so many response to the mis-use of Excel.
Its fair to say, most of us never had any training for Office or even read manuals. A blank Word page easily overwhelms a beginner. Stuff like adding boxes, tables, bullets and auto numbering.. it freaks out the novice. In excel, you can bypass all those by typing on the cells.

On a similar vein, back in those halcyon days I was creating and printing my own inlays for CDs using Word97... until my IT shop introduce me to Avery templates!
 

Laura Knotek

Retired Moderator
Mar 31, 2012
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Didn't expect so many response to the mis-use of Excel.
Its fair to say, most of us never had any training for Office or even read manuals. A blank Word page easily overwhelms a beginner. Stuff like adding boxes, tables, bullets and auto numbering.. it freaks out the novice. In excel, you can bypass all those by typing on the cells.

On a similar vein, back in those halcyon days I was creating and printing my own inlays for CDs using Word97... until my IT shop introduce me to Avery templates!
I despise Avery templates! Trying to make address labels for greeting card envelopes was a PITA that took me over two hours. I could have handwritten the things in less time.
 

N_LaRUE

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Apr 3, 2013
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How do DC transformers even work? Constant magnetic field won't induce current in the second coil.

There has to be semiconductors, I think.
Keep in mind that DC distribution isn't the same as AC. Transformers typically are not used.

There's several papers you can read online about this if you're interested.

There's more and more use of DC over AC but it's adoption universally will probably never happen.
 

Rose640

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Keep in mind that DC distribution isn't the same as AC. Transformers typically are not used.

There's several papers you can read online about this if you're interested.

There's more and more use of DC over AC but it's adoption universally will probably never happen.

I did read a little bit, since I got curious about it. From what I understand, they use transformers to step up the signal, convert to DC, it goes to transmission lines to a certain point, invert back to AC, step down, then goes the usual bussines.

My trouble with this were losses in the process of AC to DC and backwards. I can't seem to find anything on this. But I have a general understanding that the losses in the semiconductors are significantly smaller compared to those in transmission lines with AC.
 

N_LaRUE

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I did read a little bit, since I got curious about it. From what I understand, they use transformers to step up the signal, convert to DC, it goes to transmission lines to a certain point, invert back to AC, step down, then goes the usual bussines.

My trouble with this were losses in the process of AC to DC and backwards. I can't seem to find anything on this. But I have a general understanding that the losses in the semiconductors are significantly smaller compared to those in transmission lines with AC.
Yes inverters are very good and losses are low.

Basically the inverter converts AC to DC. The DC runs at RMS AC.

The beauty of using inverters is the control you have as well

They are constantly coming down in price too and getting bigger.
 

N_LaRUE

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So this week has probably been the hardest so far with this lockdown.

I think it's partially due to the fact last weekend was a long weekend and I couldn't do anything.

I had plans to go to the farm etc.

On top of that just the feeling of doing what you want when you want is itching beneath the surface. The simple idea of just going somewhere, anywhere.

We had our first non cooked at home meal in over a month this week as well. I think I mentioned it, the vegan bakery.

I think it kind of hit home how something as simple as going to a place you want to go to has become problematic.

We're not going crazy or anything just sort of got to us a bit.
 

N_LaRUE

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Apr 3, 2013
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Also noticed some things.

We went grocery shopping yesterday. We don't go overboard with anything.

We didn't like the experience. Haven't since this thing began.

Yesterday was particularly bad. Social distancing wasn't well respected. Lots of people with masks on, some not using them right...

But the main thing was the cost. Things appear more expensive. I'm not entirely sure but just seems when we go shopping the price feels higher.

I could be imagining things...
 

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