Test Equipment Anonymous (TEA) group therapy thread

[Zucca]

Here the evil spiral....

If you interconnect to the grid you are only allowed to put on the roof what can cover your own past power need.
Problem is, I am in the process to shut down the gas utilities and move everything on electric, that why I need to put more panels on my roof.

If I do so they will probably refuse to interconnect my system with the grid.
Looks like it does not matter if there will be no energy flow from my home to the grid....

I already responded, and I have no hope somebody will understand on their side.

PS: Thanks for the correction!

[mnementh]

dragonback.jpg

Hello Mnem, what are you doing in my PSpice?

Charging up, of course. 

mnem
You uhhh... might wanna stand back. 

[mnementh]

Here the evil spiral....

If you interconnect to the grid you are only allowed to put on the roof what can cover your own past power need. Problem is, I am in the process to shut down the gas utilities and move everything on electric, that why I need to put more panels on my roof.

If I do so they will probably refuse to interconnect my system with the grid. Looks like it does not matter if there will be no energy flow from my home to the grid....

I already responded, and I have no hope somebody will understand on their side.

PS: Thanks for the correction!

Okay... so I guess I just don't understand why you want to "interconnect". Seems to me like what you need is to keep your consumer subscriber line, then configure some form of failover or power conditioning which only permits consumption of grid power when needed?

Alternately, only connect and allow them to collect data from the panels they claim you're allowed to have; keep the others on a separate system as "offline backup" or power for say your garage or for charging your EV. Once you establish that you need more capacity, then bring them online.

Or... you could stay a customer for a few months after you switch over to electric everything and establish a new usage pattern. Probably more economical in the long run. 

mnem
 

[Zucca]

I want to use the grid as backup in the events the batteries are low or the home power demand is too high for the inverters.
I am happy to pay a 12 dollars fee/month for the grid interconnection aka my emergency generator.

I guess I could survive the bidirect. meter fee if they allow me to put what I want on my roof.

[mnementh]

I guess then you need to decide if it's worth being a customer for another 6 months so you can show a new usage pattern into the winter months, or as I suggested, put up the panels you want, but have the excess routed to a dedicated EV charging station and only bring them online once you've established what you really need.

Of course, some EVs and their charger can also be used as emergency storage/power, so that might be a valid route to consider...

mnem
 

[Zucca]

put up the panels you want

I wish! Here is how it works: the power company will be automatically notified when you apply for a permit to install the solar panels on your roof!
I bet my left pinky they want to know how many solar PV you will install and react if you install too much power on the roof.... which make sense when the customer is not crazy TEA Zucca.

[mnementh]

So? It's none of their business how many you install; only how many you are connecting to their grid. If you go off-grid, they can suck it; they have no say whatsoever in the matter.

Also, if you've given up on the micro-inverter plan due to noise and have dumb panels, no idea how they're going to connect to that anyways. 

Suppose you want to use the panels exclusively for powering a guest house, or charging your EV? Now we're right back to Nunya!

mnem
Do you have a separate garage? Maybe put some panels on that too!

[mnementh]

Uggghhh...

Okies... anybody got any tech ref on the monitors used in these HP scopes? I understand the difference between the two implementations is the 54621D and family use 32-grayscale palette, while the 54600A and family use a 2-grayscale palette.

54645A/54600A use HP 2090-0316/DataRay CDM-7SF191, the 54621D uses HP 2090-0384/DataRay CDM-7SX191. My searches in the available HP SMs and on the internet turned up bupkis.

Before I go guessing based on poking around with my scope, does anybody here have actual pinouts and or schematic for these monitors?

Tomorrow I figured I'd start looking at the  CLIP package from the 54645A and see what I can find there. Maybe lookit the video chip on each and see if I can find some datasheets. 

mnem
 

[Zucca]

So? It's none of their business how many you install; only how many you are connecting to their grid. If you go off-grid, they can suck it; they have no say whatsoever in the matter.

Believe the more I dig into it, the more I fear you are wrong. If you apply for a solar PV permit, the power company needs to give an okay and react if something is out of order.
I really hope you are right regardless where the power is going, and I will find that out for sure. Problem is how long it will take.
You already read how they responded...

Also, if you've given up on the micro-inverter plan due to noise and have dumb panels, no idea how they're going to connect to that anyways. 

µinverter make sense if there is an uncontrolled shade during the day, if not it is a waste on money.

[mnementh]

I forget... where did you touch down in the States, if you don't mind sayin'?

mnem
please not Texas... please not Texas... please not Texas...

[Zucca]

South Carolina.

[mnementh]

Hmmm... SC seems pretty rabidly Republican since Reagan... not sure how that relates to Big Energy domination in the state. 

Of course where I lived in Tejas is known as "The Energy Corridor" for a reason; they own everything and everyone from top to bottom. That kind of corporate cronyism is exactly the sort of thing I'd expect there.

I wish you luck, my friend. I do hope you'll be able to get free of the yoke.

mnem
*knocks self unconscious with a 4-aught mallet*

[bd139]

This is extremely cool for an electronics book.

No Starch Press. Open Circuits: The Inner beauty of electronic components:

https://nostarch.com/open-circuits

Chapter 1 PDF https://nostarch.com/download/OpenCircuits_Chapter1.pdf

I will buy a hard copy of that when it comes out.

[AVGresponding]

The wedge does form if you do the 2nd crimp far enough away; it forms between the 2 crimps. A mm wide and deep (less, really) is all the wedge needs be to provide more than adequate mechanical strength. When I talk of the 2nd crimp being "for good measure" it is to increase the contact area under compression for lowest resistance, not mechanical strength.

These are not brake cables or the like; mechanical strength does not need to be that much in engineering terms to be stronger than any mechanical stress it should ever experience.   mnem   

You haven't seen how some "engineers" rag on cables connecting big batteries in big strings... you'd think the prospect of instant death if there's a serious short would moderate their behaviour, but as the old saying goes "familiarity breeds contempt".

If you do the arithmetic, you'll see that even a single crimp will have more surface contact area than the cable CSA. I'm not saying it's inherently bad, I'm just saying I prefer the guaranteed mechanical strength over the possible few nano-ohms difference a second crimp makes.

Mostly these things will only make a difference in edge cases; I routinely "crimp" 10-95mm² lugs with my trusty 2PH and a hammer (only if I don't have a proper crimper to hand and it needs to be done NOW. Bigger than 95mm² and I need a hydraulic crimper which I don't have, so those have to wait until it gets hired). Haven't burned any buildings down yet.   

I think we've both come to a similar understanding of what's important when making heavy-ass cables (heavy ass-cables def need to be made for mechanical strength FIRST  ) ; just coming at it from different directions. I spent a fair bit of time doing scale RC drag racing, where fractions of a ohm do make a difference you can see on the clock, then working on big forklifts as a young mechanic... so I'll just say it can matter. 

When you say "rag on cables", I'm guessing you mean something different than I would? Over here, to "rag on" something means to "frequently, repeatedly denigrate" whatever it is... ie "In the TEA thread, we always rag on RIFAs and tants!"

So from the context, I'm guessing you mean something like "to put it on carelessly" or to "assemble poorly and without regard for proper procedure"...? 

mnem
*luggable... barely*

Nano-ohms making a difference? Oh come on, even a few micro-ohms would be essentially undifferentiable at those loads. Milliohms, yes, fair enough.

Here, "ragging on" means physically abusing them. Such as dragging a part string of say, ten 12V 38Ah along the metal racking by the battery cable on the end one, lifting the batteries into place by the cable, stuff like that.



Also, what the actual fuck?!?



Piss takers! If there's obviously parts missing, the description should say so, and if they are unsure, they should say so, and have pics.

[tggzzz]

If you interconnect to the grid you are only allowed to put on the roof what can cover your own past power need.
Problem is, I am in the process to shut down the gas utilities and move everything on electric, that why I need to put more panels on my roof.

In the UK gas is much cheaper than electricity, and is commonly used for central heating, water heating, and cooking.

It sounds like you need to establish a new electricity consumption pattern in advance. In that case you will need to determine how long the power company require before they regard it as the consumption pattern. Local knowledge will be required.

[Specmaster]

<snip>

gotta' agree with the dragon on this one.

with those two T-15 screws missing from the back the cabinet will almost fall off on its own.  (don't ask how i know)

even if you did not know there was supposed to be a display board inside, how could you not notice the ribbon cables hanging loose inside?

will be interesting to see how it all plays out.

edit  just looked and there are supposed to be 3 screws back there.  mine is missing one.

Agreed about the screws and the ribbon cable hanging loose etc, but I'm talking about the dragons claim that it is "not being as described", if you actually read the sellers description of the item, it fits the description precisely as the seller states

   "Condition:    
   
Overall Condition    AS-IS (Please view all pictures)
Cosmetics    Please view all pictures
Completeness    As seen in pictures
Functionality    AS-IS (Powers on / Unable to test further)"

They do mention that it was missing the handle, hence why I asked the dragon "Have you powered it up?, did the lights come on? ", if so then it matched the description as the seller also states that the unit is as shown in the photos. I was playing "Devil's advocate".

Now I may be totally wrong here, but I suspect that the seller is not a one-man band and so it is a reasonable assumption that the item might have been tested and packed by someone who does not have a clue what they are doing, maybe a school-leaver etc., the back may not have come off while they were wrapping it, therefore they would not have known the ribbon cables were hanging loose inside, who knows 

[tggzzz]

This is extremely cool for an electronics book.

No Starch Press. Open Circuits: The Inner beauty of electronic components:

https://nostarch.com/open-circuits

Chapter 1 PDF https://nostarch.com/download/OpenCircuits_Chapter1.pdf

I will buy a hard copy of that when it comes out.

I've seen that before, and I like the the diagrams, clarity of the photos, and the brevity of the informative description. Brevity is all too rare nowadays.

That there are also diagrams and information indicates that careful thought has gone into how to educate the reader. Also all too rare nowadays.

<Carefully avoids standard diatriabe about yootoob talking-head vids, for brevity>

[tautech]

Forgive the dumb question, but why not just put that tool in a vice to squeeze it smoothly instead of hammering it ?! 
The smooth progressive action of the vice would be kind to the lug wouldn't it.

I mean a real big/full size garage vice of course, not the tiny vice we use in the lab, that goes without saying !

With a little care you can indeed make very serviceable crimps in a vise if you know how.
Not so much with the smaller cable sizes however in a permanent installation where there will be zero vibration or rarely a need to disconnect it, then bucket type lugs, those without a opening at the bottom of the bucket then soldering on crimps works just fine however a cleaner job is done with a Propane torch rather than Oxy/Acetylene.

Crimps in the vice with commercially or homemade lugs really need a reasonably heavy wall lug to withstand the compression as only 2 sides of the crimp are contacted on.
First you need a crimp that well matches the cable size and then the Hex head of a bolt or stout nut for just one of the Hex faces to be squeezed into the side of the barrel of the crimp to leave a deep rectangle pressed into the crimp.
I've used this method with 100% success over many decades on heavy welder leads and with a couple of layers of shrink sleeve for strain relief it's a quick solution if you don't have some blowtorch handy or your sparky mate with the good crimpers has gone AWOL.

Edit
However care must be taken where one might do such non-standard procedures so to properly consider the risk to life, limb or property.

Hey Vince, about the vise crimp we're trying to achieve with a Hex nut or bolt head, similar to this done with a commercial tool with a plunger pressing into a Vee .... this one a double - crimp some are + plungers.

Anyways, just the flat of a Hex done longways or across the lug depending on the size of the lug and the bolt/nut hex used to squeeeeze it together.
This is for a pis ant old and little 140A caddy welder lead, didn't check but probably 25mm² cable and 13mm hole in the lug. Muppets that made it couldn't even be bothered to sleeve it for bending strain relief so it's starting to show signs of early failure. 

Final word:
Any lug crimp for mains must be done with approved tools to meet compliance.......trying to get my sparky mate's old crimpers that he can no longer use for NZ mains work and comply with a COC. (cert of compliance)

OH it looks like this lug is soon to part with that wire !

Time to get that Hex bolt and vice in action, replace that crimp and show us nice pictures ! I am waiting ! 


Going to bed, good night....   

Sorry buddy, not happening as it's a welder I rarely use and therefore as sad as the joint looks it will last me until I am no more. 
However AWOL Sparky mate dropped by today and we had a chat about crimped lugs and here in NZ now only Hex crimps are permitted for any mains feeds and crimp lugs must match cable size used and with the correct Hex die selected which when all are properly matched and a properly tight crimp made the mirrored cable/crimp size in the Hex die is formed into the lug upon crimping.
This results in the electrical inspectors just requiring a glance to know if the crimp has been properly done.
Just sometimes officialdom has some good legislation !

[Vince]

Dear Kiwi,

I am extremely surprised by your reaction and I shall soon be seeking experienced, professional psychological help in order to recover, heal, overcome.... this traumatizing, severe disappointment.   

[Specmaster]

Seen today on Ebay UK, anybody requiring a 50Mhz LA, starting bid of only £15...

https://www.ebay.co.uk/itm/255609408885
WTF is this?

[bd139]

That’s absolutely vile 

Yodel 3 stops away with my PCM test set. HP tear down coming up this afternoon.

[nixiefreqq]

<snip>

gotta' agree with the dragon on this one.

with those two T-15 screws missing from the back the cabinet will almost fall off on its own.  (don't ask how i know)

even if you did not know there was supposed to be a display board inside, how could you not notice the ribbon cables hanging loose inside?

will be interesting to see how it all plays out.

edit  just looked and there are supposed to be 3 screws back there.  mine is missing one.

Agreed about the screws and the ribbon cable hanging loose etc, but I'm talking about the dragons claim that it is "not being as described", if you actually read the sellers description of the item, it fits the description precisely as the seller states

   "Condition:    
   
Overall Condition    AS-IS (Please view all pictures)
Cosmetics    Please view all pictures
Completeness    As seen in pictures
Functionality    AS-IS (Powers on / Unable to test further)"

They do mention that it was missing the handle, hence why I asked the dragon "Have you powered it up?, did the lights come on? ", if so then it matched the description as the seller also states that the unit is as shown in the photos. I was playing "Devil's advocate".

Now I may be totally wrong here, but I suspect that the seller is not a one-man band and so it is a reasonable assumption that the item might have been tested and packed by someone who does not have a clue what they are doing, maybe a school-leaver etc., the back may not have come off while they were wrapping it, therefore they would not have known the ribbon cables were hanging loose inside, who knows 

point taken.

ebay does say:

For parts or not working: The item does not function as intended and is not fully operational. This includes items that are defective in ways that render them difficult to use, items that require service or repair, or items missing essential components. See the seller's listing for full details

however, it does seem like maybe there was some misdirection going on?   when some one keeps telling you to look at the pictures of the outside of the box and then the problem is on the inside, it does make you wonder.

BUT i would not jump on the seller with both feet until he has had a chance to respond.  like you say.....the guy who did the packing might be a drone and may not have a clue.  hopefully there is a responsible adult around who will see the dragons pictures and realize that their written description was incomplete and did not properly describe the condition of the item.   (edit..."see the sellers's listing for full details"  he really did not provide any "details")

[bd139]

In the world of commerce the customer is always right. Make the most of it 

[Vince]

Seen today on Ebay UK, anybody requiring a 50Mhz LA, starting bid of only £15...

https://www.ebay.co.uk/itm/255609408885
WTF is this?

Well it's pretty obvious, it's some kind of screen saver, to protect the precious CRT ! 

[Vince]

ebay does say:

For parts or not working: The item does not function as intended and is not fully operational. This includes items that are defective in ways that render them difficult to use, items that require service or repair, or items missing essential components.

 See the seller's listing for full details
[...]

To me this means that yes, a missing board or other essential part is acceptable... SO LONG as the seller mentions it and the buyer therefore can know what he is buying !!!
Which sounds only fair and logical for both parties....

In this case the missing board was not mentioned nor even visible in the pictures, so that's breaching the terms to me ?!   

I think Dragon has a case...