Test Equipment Anonymous (TEA) group therapy thread

[Specmaster]

Judging by that picture, it's running Microsoft DOS 3.1!   

The sticker says Windows 95.

Well Windows 95, DOS3.1 or whatever it is you won't find any new software for those platforms, especially ones that would need anything like 32 GB of RAM, let alone the 64 GB max that Vince would like, so I'm guessing he's running a Linux system. But surely even Linux must require certain CPU's, and could Linux handle 64 GB RAM?

[dl6lr]

Judging by that picture, it's running Microsoft DOS 3.1!   

As this is IBM, it is probably running PC-DOS!

[Saskia]

you can only use that amount of RAM if you have a 64 bit CPU which the old thingies do not. ~4 GB would be maximum with 32 bit CPUs (with about 3.5GB actually usable)
Win 95 does not run on 64bit CPUs. Actually it has a hard time on 32bit CPUs ...

[Saskia]

Now for a real question wrt photovoltaics (sorry, I do not have enough experience in this matter and I am not too arrogant to admit it).

I was able to finalize the mortgage stuff and actually sign the contract for my new home. This is a Bungalow that had a flat roof but then was extended with a more or less normal roof. we have a car port/ garage and a conservatory which has a glass roof.

I would very much like to add PV due to skyrocketing energy costs over here. Now I need to find out if other buildings are casting shadows and where it would actually make sense to set this up, and if so: on which parts of the roof.

My idea:

take a portable PV cell (like one of those 50 or 100 W gizmos), fling it onto the roof and attach an electronic load. Monitor for voltage or current drop and write out a protocol. Then look if this changes dramatically over the day.
Repeat for different areas of the roof.

Note: drone flights and just taking photos would be an option in principle, however due to new legislation are a no go unless you are a licensed operator ...

Does my approach make sense, or am I missing something ?

[Andrew_Debbie]

 But surely even Linux must require certain CPU's, and could Linux handle 64 GB RAM?

Linux runs quite well on older CPUs.   64GB RAM requires 64-bit hardware. 

I have 5 or 6 working Mac Pros from 2006-2010 running Ubunu.    Two are in active use on my desk at work.  One is running 20.04LTS server and the other is a development machine.  I think it has 18.04 and 20.04 desktop at the moment.

These have 64-bit Intel Xeon processors.  Most of them are dual CPUs with a total of 8-cores.

One got new server class disks a few years ago.  Other than disks  they are still running the original hardware. 

They are still 'fast enough' to be useful.    Lots of 'slow' cores.    The heating in the building is not working so I use them for heat as well as compute power.

 

Code: [Select]

xxx@odin:~$ cat /proc/cpuinfo
processor : 0
vendor_id : GenuineIntel
cpu family : 6
model : 44
model name : Intel(R) Xeon(R) CPU           E5620  @ 2.40GHz
stepping : 2
microcode : 0x1f
cpu MHz : 1596.200
cache size : 12288 KB
physical id : 0
siblings : 8

<CUT....>  .

processor : 15
vendor_id : GenuineIntel
cpu family : 6
model : 44
model name : Intel(R) Xeon(R) CPU           E5620  @ 2.40GHz
stepping : 2
microcode : 0x1f
cpu MHz : 1596.217
cache size : 12288 KB
physical id : 1
siblings : 8
core id : 10
cpu cores : 4


[nfmax]

Now for a real question wrt photovoltaics (sorry, I do not have enough experience in this matter and I am not too arrogant to admit it).

I was able to finalize the mortgage stuff and actually sign the contract for my new home. This is a Bungalow that had a flat roof but then was extended with a more or less normal roof. we have a car port/ garage and a conservatory which has a glass roof.

I would very much like to add PV due to skyrocketing energy costs over here. Now I need to find out if other buildings are casting shadows and where it would actually make sense to set this up, and if so: on which parts of the roof.

My idea:

take a portable PV cell (like one of those 50 or 100 W gizmos), fling it onto the roof and attach an electronic load. Monitor for voltage or current drop and write out a protocol. Then look if this changes dramatically over the day.
Repeat for different areas of the roof.

Note: drone flights and just taking photos would be an option in principle, however due to new legislation are a no go unless you are a licensed operator ...

Does my approach make sense, or am I missing something ?

It might be easier to try measuring* the horizon elevation (from approximately the eaves height) over a range of angles, then use a sun position calculator to get the times of true local sunrise & sunset for each day of the year, taking the horizon elevation into account. NASA/NOAA made algorithms available for this, and there are implementations floating around on the net. I used Matlab when I did it, but I no longer have access to a Matlab license, unfortunately

* Your chance to make yourself an astrolabe!

[DC1MC]

Well Scheiße  , lost the two (defective) Agilent scopes to someone that bit a day ago 20 something EUR, because Gixen failed me  

[capt bullshot]

My idea:

take a portable PV cell (like one of those 50 or 100 W gizmos), fling it onto the roof and attach an electronic load. Monitor for voltage or current drop and write out a protocol. Then look if this changes dramatically over the day.
Repeat for different areas of the roof.

Note: drone flights and just taking photos would be an option in principle, however due to new legislation are a no go unless you are a licensed operator ...

Does my approach make sense, or am I missing something ?

Ideally you'd just need one sunny day to get your results, but results may be different for different seasons. You don't need any clever MPP tracking, set the load to CV (constant voltage) mode at the typical (max. power delivered) voltage of the panel and monitor the current, or just short the panel with an Ampere Meter and monitor the current.

Simplest method: Just hold out your head where you want to place the PV panels and take a look around. The guys that installed the PV on my home used a small camera device which looked purpose built. I believe it was just a tablet or smartphone with a clever app that could give you some forecast when there'll be significant shading and how much impact this has on the total revenue.

[DC1MC]

My idea:

take a portable PV cell (like one of those 50 or 100 W gizmos), fling it onto the roof and attach an electronic load. Monitor for voltage or current drop and write out a protocol. Then look if this changes dramatically over the day.
Repeat for different areas of the roof.

Note: drone flights and just taking photos would be an option in principle, however due to new legislation are a no go unless you are a licensed operator ...
Does my approach make sense, or am I missing something ?

Ideally you'd just need one sunny day to get your results, but results may be different for different seasons. You don't need any clever MPP tracking, set the load to CV (constant voltage) mode at the typical (max. power delivered) voltage of the panel and monitor the current, or just short the panel with an Ampere Meter and monitor the current.

Simplest method: Just hold out your head where you want to place the PV panels and take a look around. The guys that installed the PV on my home used a small camera device which looked purpose built. I believe it was just a tablet or smartphone with a clever app that could give you some forecast when there'll be significant shading and how much impact this has on the total revenue.

Install "Solar Survey" and follow the instruction don#t bother with R. Goldberg machines 

[Specmaster]

Now for a real question wrt photovoltaics (sorry, I do not have enough experience in this matter and I am not too arrogant to admit it).

I was able to finalize the mortgage stuff and actually sign the contract for my new home. This is a Bungalow that had a flat roof but then was extended with a more or less normal roof. we have a car port/ garage and a conservatory which has a glass roof.

I would very much like to add PV due to skyrocketing energy costs over here. Now I need to find out if other buildings are casting shadows and where it would actually make sense to set this up, and if so: on which parts of the roof.

My idea:

take a portable PV cell (like one of those 50 or 100 W gizmos), fling it onto the roof and attach an electronic load. Monitor for voltage or current drop and write out a protocol. Then look if this changes dramatically over the day.
Repeat for different areas of the roof.

Note: drone flights and just taking photos would be an option in principle, however due to new legislation are a no go unless you are a licensed operator ...

Does my approach make sense, or am I missing something ?

I think what you need to do is just download a program called suncalc on this link, https://www.suncalc.org/. It will open a world map, and then you just need to click on your approx location, and then it will zoom in to that location and dragging the map around and zooming in you will get to street maps. To help you in this quest, there is also an option to use satellite view and look for your new house and click on the roof and will see something like this.
Then you can play around with the time of day and also month / day and see which part of your house will get the maximum amount of useable sunlight and can also see if other buildings are likely to put yours in shade, but to be honest you can do that visually.

[Vince]

@Vince the price I quoted was for a complete PC with a Ryzen 3600. I could throw in an additional 16 GB if needed.
I am sorry, components are not cheap.
I

Well yes of course ! Best you sell it to someone who has the money for such H/W.

500 Euros is an absolute fortune I can't spend right now. Am only willing to spend this much money if I get 100% what I want.
If ever my computer dies before I get to replace it, I will just try to fix it / get it going as cheaply as possible, since any money put into getting it going will be 100% wasted money.

Computer is 15 years old now, so even a brand new bottom of the barrel 50 Euros smartphone would probably be powerful enough to replace it. Just hook the k/B and screen to it via USB-C maybe.... I don't know these things.

[Vince]

Thanks !
... I was just joking of course... will just make do with what I have and cross fingers it holds up.

500 Euros is more than I planned to spend on the entire new system ! 

I will keep my old 17" Samsung Monitor and 15 year old Cherry K/B that I love. Computer case I have a (well, 3 of them in fact) old Tower  IBM Aptiva that I would like to rework (proprietary case, ATX was not yet widespread...) to accept a uATX M/B. Need to take measurements to see what dimension M/B would fit. Need mid-range CPU that takes little power/small fan/quiet, an on-board graphics will be just fine as I don't do fancy modern 3D gaming.  Then 32GB of RAM, a 500 SSD, and that should do it ! Ah yeah, a PSU too, but a low power one so hopefully cheap.
Most important is quantity of RAM.32GB minimum and hopefully with room for 64GB later as S/W requirements keep growing over the next 10 years.

Will enquire on here when the time comes, about particular products...

Question is what OS are you running, and what will you be running after the upgrade?

Same OS I am running now on my current 15 yo machine : Linux.  XUbuntu 16.04 to be more precise.

[tautech]

Now for a real question wrt photovoltaics (sorry, I do not have enough experience in this matter and I am not too arrogant to admit it).

I was able to finalize the mortgage stuff and actually sign the contract for my new home. This is a Bungalow that had a flat roof but then was extended with a more or less normal roof. we have a car port/ garage and a conservatory which has a glass roof.

I would very much like to add PV due to skyrocketing energy costs over here. Now I need to find out if other buildings are casting shadows and where it would actually make sense to set this up, and if so: on which parts of the roof.

My idea:

take a portable PV cell (like one of those 50 or 100 W gizmos), fling it onto the roof and attach an electronic load. Monitor for voltage or current drop and write out a protocol. Then look if this changes dramatically over the day.
Repeat for different areas of the roof.

Note: drone flights and just taking photos would be an option in principle, however due to new legislation are a no go unless you are a licensed operator ...

Does my approach make sense, or am I missing something ?

Go with online websites for optimal PV installation so to get the best/fastest return on investment.
Like Spec posted or here's another random one:
https://news.dualsun.com/co-en/12/2014/what-is-the-optimal-orientation-and-tilt-angle-for-solar-panels/

[Vince]

Thanks !
... I was just joking of course... will just make do with what I have and cross fingers it holds up.

500 Euros is more than I planned to spend on the entire new system ! 

I will keep my old 17" Samsung Monitor and 15 year old Cherry K/B that I love. Computer case I have a (well, 3 of them in fact) old Tower  IBM Aptiva that I would like to rework (proprietary case, ATX was not yet widespread...) to accept a uATX M/B. Need to take measurements to see what dimension M/B would fit. Need mid-range CPU that takes little power/small fan/quiet, an on-board graphics will be just fine as I don't do fancy modern 3D gaming.  Then 32GB of RAM, a 500 SSD, and that should do it ! Ah yeah, a PSU too, but a low power one so hopefully cheap.
Most important is quantity of RAM.32GB minimum and hopefully with room for 64GB later as S/W requirements keep growing over the next 10 years.

Will enquire on here when the time comes, about particular products...

Question is what OS are you running, and what will you be running after the upgrade?

Judging by that picture, it's running Microsoft DOS 3.1!   

@Vince, good for you, waste is wasteful, no need to throw away a perfectly good case.

Yeah I started "collecting" this model of case 15 years ago when I bought my current computer. I could not find any case I liked, but I liked this old IBM Aptiva case. So for all these years I have always had the plan to one day stuff a modern motherboard into it, even though it does require some hacking/metal work as it's an old proprietary IBM design, it does not conform to the ATX standard at all, not even close. I also like the old "beige " Apple computer cases from the early/mid '90s, might go this route too.  Depends on availability / condition / price, no idea what the market is like, have not looked seriously into it so far.  Might do an Aptiva case for my main desktop computer, and an old beige Apple tower for the lab/workbench space, why not...

[Vince]

Judging by that picture, it's running Microsoft DOS 3.1!   

The sticker says Windows 95.

Well Windows 95, DOS3.1 or whatever it is you won't find any new software for those platforms, especially ones that would need anything like 32 GB of RAM, let alone the 64 GB max that Vince would like, so I'm guessing he's running a Linux system. But surely even Linux must require certain CPU's, and could Linux handle 64 GB RAM?

Well yes of course I will be running Linux  on it !    Have been running Linux since as my main and only OS since 2002.

Works just fine on my 15 yo machine, a core2duo which is a 64 bits CPU, so am using a 64bit Linux kernel, with 8GB of RAM. Well 64bit kernel has been the default one for Ubuntu for 10 years or so. 32 bit kernel version is still available of course, for '90s machines like the old Appel beige machine. One of the big advantage of Linux is it lets you keep your H/W for many many years. Machine is 15yo and still runs just fine, still has drivers for ancient stuff. I could hook up a ZIP drive on a parallel port and I bet it would still work.
Putting windows  anything other than XP on my machine would not go well, or at all, and it would not support my old H/W either, like my 1997 HP Lasertjet 6P Printer I guess. But running a modern Linux OS on same machine works just fine.  So I say, Linux will save the planet, keep your H/W for much longer !
will also save your wallet.. win-win ! 

[Saskia]

you could also try FreeBSD which is the better OS ...

[Cerebus]

I would very much like to add PV due to skyrocketing energy costs over here. Now I need to find out if other buildings are casting shadows and where it would actually make sense to set this up, and if so: on which parts of the roof.

My idea:

take a portable PV cell (like one of those 50 or 100 W gizmos), fling it onto the roof and attach an electronic load. Monitor for voltage or current drop and write out a protocol. Then look if this changes dramatically over the day.
Repeat for different areas of the roof.

Note: drone flights and just taking photos would be an option in principle, however due to new legislation are a no go unless you are a licensed operator ...

Does my approach make sense, or am I missing something ?

As others have noted, plenty of software available to do the heavy lifting nowadays. One point to note however: because of the precise construction of solar cell arrays they are much more sensitive to partial shading than an naïve understanding would lead one to expect. One would think that if say 10% of a panel was shaded one would expect a 10% reduction in output but that is not the case; if a long thin shadow covers 10% of the panel but 100% of the strings of cells then the output can be almost nothing. The same applies to a shadow across a corner of a panel that might cover a small percentage of the panel area but covers a significant proportion of the strings on the panel.

The reason for this is that a panel is constructed as several strings of cells in series, with the strings then themselves connected in series. There are bypass diodes between strings so that if a string is shaded and not producing current then the current from the other strings bypasses it to continue producing power and also to avoid causing damage by creating hot spots. A picture makes it much clearer:




It's a bit like the situation with a battery pack where one of the battery cells can get reverse biased if it is undervoltage with respect to the rest of the cells in the pack. Thus if just one cell out of all the cells that make up a string is shaded it can take the whole string out of use.

So when watching out for shading of a panel, make sure to watch out for partial shading that one might naïvely think would be relatively insignificant. Dave Jones got caught out by this recently when he relocated some of his panels and put them where the apparently trivial shadow from a TV antenna pole significantly reduced the output from the whole array.

[Cerebus]

Just had a prime example of the cussedness of cats.

Madam comes and sits on the footstool, staring at me on the sofa. This she usually does when she wants something. As I wanted a fresh coffee I got up and led/followed her to the kitchen as 'the stare' usual means "Kitchen slave. my bowl is empty! Fill it!". Bowl wasn't empty but she decided to have a mouthful or two "While I'm here. While I have a slave to look upon the magnificence of my feasting.".

I turn the coffee machine on to warm up. Madam moves to the head of the stairs, probably wanting the doorman (me too) to let her out. I'm waiting for adequate heat and pressure on the coffee maker so I go and indulge her. She just sits at the top of the stairs and doesn't want to go down to the door. I go back and make coffee.

I now (perhaps 60-90 seconds after the first time) walk back towards the top of the stairs, this time balancing coffee etc. Madam immediately trots downstairs with an over-the-shoulder look that says "What kept you, slave?". I would swear that she calculates "What would be the most inconvenient moment in this whole sequence when I tell the slave what I want, and that I want it now?".

[Robert763]

A better solution than diodes for panel shading is proper optimisers. These are DC-DC converters and keep each panel at it's optimum load point. Unfrotunatly there is a lot of "sharp" advrtising that calls doide modules optimisers. There is also theption of one micro inverter DC-AC converter per panel.
Some optimisers do cause a lot of EMI though.

[tautech]

So when watching out for shading of a panel, make sure to watch out for partial shading that one might naïvely think would be relatively insignificant. Dave Jones got caught out by this recently when he relocated some of his panels and put them where the apparently trivial shadow from a TV antenna pole significantly reduced the output from the whole array.

Hence the move to panels with microinverters. 

[Specmaster]

Judging by that picture, it's running Microsoft DOS 3.1!   

The sticker says Windows 95.

Well Windows 95, DOS3.1 or whatever it is you won't find any new software for those platforms, especially ones that would need anything like 32 GB of RAM, let alone the 64 GB max that Vince would like, so I'm guessing he's running a Linux system. But surely even Linux must require certain CPU's, and could Linux handle 64 GB RAM?

Well yes of course I will be running Linux  on it !    Have been running Linux since as my main and only OS since 2002.

Works just fine on my 15 yo machine, a core2duo which is a 64 bits CPU, so am using a 64bit Linux kernel, with 8GB of RAM. Well 64bit kernel has been the default one for Ubuntu for 10 years or so. 32 bit kernel version is still available of course, for '90s machines like the old Appel beige machine. One of the big advantage of Linux is it lets you keep your H/W for many many years. Machine is 15yo and still runs just fine, still has drivers for ancient stuff. I could hook up a ZIP drive on a parallel port and I bet it would still work.
Putting windows  anything other than XP on my machine would not go well, or at all, and it would not support my old H/W either, like my 1997 HP Lasertjet 6P Printer I guess. But running a modern Linux OS on same machine works just fine.  So I say, Linux will save the planet, keep your H/W for much longer !
will also save your wallet.. win-win ! 

Sounds great being able to use H/W for longer but what I have never fully understood is about the actual software that runs on Linux, is it dedicated software or Windows based software? And if it is dedicated software, where is it available from etc? Sounds like it might be expensive and difficult at the same time to replace all the useful Windows SW with Linux versions, and what about games etc. I really don't know enough about this, so it keeps putting me off from making the switch, but now finances are becoming far tighter and for at least, to continue with Windows based gear, I'll need to upgrade to version 11 and that needs a total replacement of my current H/W 

[Cerebus]

A better solution than diodes for panel shading is proper optimisers. These are DC-DC converters and keep each panel at it's optimum load point. Unfrotunatly there is a lot of "sharp" advrtising that calls doide modules optimisers. There is also theption of one micro inverter DC-AC converter per panel.
Some optimisers do cause a lot of EMI though.

The bypass diodes I'm talking about are built into most standard commercial panels, several in each panel. This isn't "bypass the panel" but "bypass the string within the panel". I'm not talking about bypasses external to the panel which, by dint of being a visible component, are less likely to trip up the unwary. These aren't 'optimisers' (though no doubt some shady vendors might characterise them as such) but built-in protection components.

I was vaguely aware of their existence but hadn't realised the impact they could have on total output during partial shading events until Dave came a cropper with his antenna shadow.

[Specmaster]

Just had a prime example of the cussedness of cats.

Madam comes and sits on the footstool, staring at me on the sofa. This she usually does when she wants something. As I wanted a fresh coffee I got up and led/followed her to the kitchen as 'the stare' usual means "Kitchen slave. my bowl is empty! Fill it!". Bowl wasn't empty but she decided to have a mouthful or two "While I'm here. While I have a slave to look upon the magnificence of my feasting.".

I turn the coffee machine on to warm up. Madam moves to the head of the stairs, probably wanting the doorman (me too) to let her out. I'm waiting for adequate heat and pressure on the coffee maker so I go and indulge her. She just sits at the top of the stairs and doesn't want to go down to the door. I go back and make coffee.

I now (perhaps 60-90 seconds after the first time) walk back towards the top of the stairs, this time balancing coffee etc. Madam immediately trots downstairs with an over-the-shoulder look that says "What kept you, slave?". I would swear that she calculates "What would be the most inconvenient moment in this whole sequence when I tell the slave what I want, and that I want it now?".

Yeah, I get that too from time to time, but overall, they do compensate in other ways, they are great company, one is more of a techno cat, she loves computer screens, in fact anything with a screen on and can play games or interesting videos, and she's there, and she is so predictable when it comes to putting them to bed at night. She is also very vocal and loves to talk to us.

[ch_scr]

Just had a prime example of the cussedness of cats.

Madam comes and sits on the footstool, staring at me on the sofa. This she usually does when she wants something. As I wanted a fresh coffee I got up and led/followed her to the kitchen as 'the stare' usual means "Kitchen slave. my bowl is empty! Fill it!". Bowl wasn't empty but she decided to have a mouthful or two "While I'm here. While I have a slave to look upon the magnificence of my feasting.".

I turn the coffee machine on to warm up. Madam moves to the head of the stairs, probably wanting the doorman (me too) to let her out. I'm waiting for adequate heat and pressure on the coffee maker so I go and indulge her. She just sits at the top of the stairs and doesn't want to go down to the door. I go back and make coffee.

I now (perhaps 60-90 seconds after the first time) walk back towards the top of the stairs, this time balancing coffee etc. Madam immediately trots downstairs with an over-the-shoulder look that says "What kept you, slave?". I would swear that she calculates "What would be the most inconvenient moment in this whole sequence when I tell the slave what I want, and that I want it now?".

"He who does not like cats, will not get a beautiful women" - chinese proverb
...make of that what you will...

[Cerebus]

Yeah, I get that too from time to time, but overall, they do compensate in other ways, they are great company, one is more of a techno cat, she loves computer screens, in fact anything with a screen on and can play games or interesting videos, and she's there, and she is so predictable when it comes to putting them to bed at night. She is also very vocal and loves to talk to us.

From "time to time" rather than continuously? Probably means that they're building up to something. You'll better get yourself a copy of this book, before it it too late.

She is also very vocal and loves to talk to us.

You do understand that is an unrelenting string of orders, don't you? Orders that you appear to be ignoring. Again, I refer you to the previous volume while you still have time to save yourself.