SimBox NG

pit-build

#241

It’s BIG!
I don’t understand? It looked so small in the design drawings…


#242

So, I needed to cut the powercable to get it through a hole in the frame.
Then I found this cool silver braided cable that I wanted to use. I got a C13 contact and a regular euro plug.

Now, the cable has three leads of 0.75mm sq. How many Amps will it take?
I have a 850W PSU, and the voltage is 230V.

W=V*A right?
A=W/V?
850/230=3,7A.

The cable should do 4ish Amps, right?


#243

I’ll normally size my conductors/ cables for 25% above calculated load due to transients, so I’d count it for a minimum of 5A, personally, but you do NOT want the conductor to be the current-limiting component in that system.

So, each lead has a cross-sectional area of 0.75mm^2, right? I’m trying to do the ampacity calculation here… Silly Metric system.


#244

Yep!

Consider it a challenge… :wink:


#245

So it’s roughly the same size as the 18 AWG power cords we use here with a NEMA 5-15P (but that’s for 120V), so I mean you should be ok.


#246

Kind of an off-the-wall question…

It looks a slight bit tall but you could put a couple of fitted cushions on top and then a fluffy throw pillow or two…and a nice quilt, a floral pattern would be nice…kind of a “nap nook”

…or if more of a table, I’m thinking of a couple of nice African Violets, a scented candle (vanilla or peach or vanilla-peach) and a “Coffee Table” book…something like “The Flowers of Nova Scotia” or “Moods in Sand”…

…just some thoughts as you reach the finish line. :sunglasses:


#247

I was thinking that his wife could just out a couple nice flower pots on top of it. :slight_smile:


#248

True…at this point SimBox NG is really in the hands of Mrs. Troll…


#249

That is the typical cross section for CEE power cords and those are usually rated 10A. Bear in mind that this holds true for actual copper conductor, if you’re unsure and this could be copper plated steel or the manufacturer isn’t true to the spec then you’re cutting it close. You can never be too sure with some of the stuff that comes out of China…

Make sure you are familiar with the regulations for Schuko plugs, there’s more to it than first meets the eye (wire termination sleeves, earth wire should have overlength, etc.).


#250

That would not be beyond Mrs. Troll’s abilities…

Mrs. Troll holds «the one who must be obeyed» title around here, which technically makes everything her domain…

Have you seen any documents on this?
The plugs are approved for DIY and the instructions does not mention any of this.
Earth wire overlength? Is that so a phase wire will get pulled out before the earth wire, if there’s no cable strain relief?


#251

Exactly. If you pull out the entire cable, the earth wire must be the last to lose contact.

There’s probably a norm for this, but it’s not that complicated. Clamping braid wire without using a wire ferrule has a much higher hazard of fire or a stray uninsulated braid going somewhere it’s not supposed to go.

Have a look at this (and disregard the clamp tool advertisement, it does look nice when clamped with a 150€ clamp tool but with a little bit of handcraft you can clamp this with pliers as well).


#252

Ok!
Duly noted.

Soldering some brass pipes on the ends of the leads should accomplish the same thing, I guess? :thinking:


#253

Erm, brass has about 28% the electrical conductivity of copper. It might work, but me being a partial sparky i’m almost legally obligated to tell you that you really shouldn’t. :man_shrugging:

I can only speak about the regulations in Austria, i’m not familiar with the ones in Norway(?). Fact of the matter is, down here companies are no longer allowed to sell cables that are not terminated with sleeves (but instead clamped directly). If you want to do it state of the art, use a sleeve, that’s my take on this.

Oh and something i missed in your upper post, even when there is a cable strain relief, the earth wire should ALWAYS be the longest one. A strain relief can slip/fail when someone trips over the wire. It’s added safety for basically no additional work.


#254

Are those sleeves copper?

The rules here is that you can make your own leads, but everything that’s considered an installation, must be done by a certified electrician.

The plugs that are sold here have regular screw terminals, and they are approved…

That said, extra safety never hurts.


#255

Tin-plated copper.

There is one type of clamp that is approved for unsleeved braids, it’s called Fahrstuhlklemme in German.

The important point is that the screw presses a flat sheet of metal against the braid and the braid is not clamped by the screw directly. If that is the case with your plug, then you’re good.

Anyways, sorry for the derail. :expressionless: But when dealing with mains voltages, it’s better to be safe than sorry.


#256

No, thank you for the input!


#257

You need to calculate the resistance of the cable and the material inside then, you know how much heat it will dispensate based on the amps you wanna push through and see if it’s in spec.

I kinda forgot the formula but it should be online somewhere, it’s been a few years since I needed to do these calculations… woops?


#258

P = U * I,

with U = R * I this becomes

P = R * I * I = R * I²

That is the power dissipated over the entire length of the conductor, if R is the resistive impedance of the entire conductor (both phase and zero conductor in series).

It’s usually easier to refer to a chart for cross sections like this one https://www.engineeringtoolbox.com/wire-gauges-d_419.html

Given a cross section of 0.75mm², a 3 core cable would be rated in the ballpark of 6 amps according to that AWG chart, which is quite conservative.

The only variable here is whether the cable manufacturer actually holds true to the spec (is the material copper and do the cables have the actual advertised cross section).


#259

I have been swamped the last two weeks so just now catching up on the progress you’ve made…outstanding work, as always, dude!


#260

The resistor code nemonic:

Bad Boys Ravage Our Young Girls, But Violet Goes Willingly.

Seriously…how do you think I passed my one EE class in College.

(I’m an ME)