Test Equipment Anonymous (TEA) group therapy thread

[shakalnokturn]

None of them, or both it's not clear

The Tenma is rated 0.6% + 40 counts on the 1000V AC range. It's reading 0.11% low on the picture. Which is pretty good I would say.

On 10VDC the 5101b is around 66ppm away from my local 10V ref.

The latter sounds good. How far is the Tenma off the local 10V ref. on the closest range?

[bd139]

Just survived first day of biggest IT project rollout I’ve had to handhold. Complete success with a couple of minor issues, mostly client self inflicted. But scary shit. 

Food then TE therapy time 

[mnementh]

So... fuck AWS...?

mnem
 

[med6753]

Just survived first day of biggest IT project rollout I’ve had to handhold. Complete success with a couple of minor issues, mostly client self inflicted. But scary shit. 

Food then TE therapy time 

You mean to say the software actually worked the first time? Holy shit, what is the world coming to? 

[bd139]

So... fuck AWS...?

mnem
 

We haven’t got the bill yet. It’ll be fuck AWS then 

Just survived first day of biggest IT project rollout I’ve had to handhold. Complete success with a couple of minor issues, mostly client self inflicted. But scary shit. 

Food then TE therapy time 

You mean to say the software actually worked the first time? Holy shit, what is the world coming to? 

After 18 months of testing and fixing yes 

[cyclin_al]

The NEC (National Electrical Code) in the USA has required polarized receptacles since the 1960s.
-Pat

So to sum it up... the entire world is "polarized" .. but only the USA actually mean to take it seriously in practice, as in RELYING on it to be true when they work on stuff or decide where to they can put their fingers...

I guess it's consistent with the usual (modern) USA tradition of protecting people against themselves all the time... with stupid safety warnings on anything and everything...  soon they will put stickers on kitchen knives : " WARNING, LETHAL WEAPON, USE WITH GREAT CARE ! DO NOT EAT ! DO NOT SLIT YOUR WRISTS ! DO NOT THROW AT YOUR KIDS ! " etc....

Not only the USA.

The people in charge in the great white north always answer "I'll have what he's having" and then point to Uncle Sam down south.

Translation:  the Canadian system is the same as the USA system for plugs and polarity.

However, not quite everything in the CEC is the same as the NEC.  Never assume...

[Specmaster]

If on the other hand as others have indicated there no legal requirements for which pin the Hot and Neutral wires are terminated at, then that is a recipe for problems.

Why?

I believe that there must be some standard that electricians have to conform to and that the connections of sockets are clearly defined as to what each is supposed to connected to, so that anything that demands a ground connection for safety can only be connected one way when the plug is plugged in, so that the switch on the equipment and any fuse in the equipment is in the Hot or Live line so that in the even of a problem, the fuse isolates the incoming supply to prevent the metal work on the equipment remaining connected to the Live and still present a dangerous situation.

I do not follow.
To me, if you have a system that is dangerously less secure if phase and neutral are flipped, then that system is faulty and needs to be fixed. If there is a difference, but the security level with the polarity switched still is high enough to fullfill the requirements in law/other rules, then there is no actual problem. (Do note that we are discussing the system safety in normal operation, not split open on the bench.)

The cases you put forward, are dealt with by the PE conductor and/or the RCB, and it is therefore important that ground mates first, and that it breaks last. Such details are catered for in most well designed plugs and sockets.   It is also obvious and fulfilled by all plug/socket systems we've discussed that PE must be unambigious.

Regardless of that case,  since you can't safely rule out two different cases,

• Isolating centre tapped transformer or Delta supply
• flipped polarity

...any safe equipment must deal with full mains potential on both conductors of the supply in a way that's no less secure than the "intended orientation".

Issue is moot, and insisting is pointless. IMNSHO.

In any well-designed system / product, the switch should be on the live side. If the supply is reversed, either because the plug is reversible or the socket incorrectly wired, then there is an inherent possible danger with the equipment, whatever it is unless it's double pole switched or double insulated. You say that the PE should protect you, as you correctly say that is designed to be the first connection on the plug / socket to make and the last to break. But that is of little consequence if the PE path in the power cord is damaged or the PE house wiring is ineffectual. The RCB is only there as a back-up safety device, not a catch-all device to allow for shoddy workmanship in the wiring installation. It is also possible for some RCB's not to trip when they should and one cause has been found in the past with DC being leaked to ground which can saturate the RCB detection mechanism which renders the device useless. This is one of the reasons why they should be tested at regular intervals to spot troubles before they become major problems, much the same as fire alarms should be tested from time to time.

A fully qualified electrician should know the correct way to terminate sockets and make sure that their work is above reproach, it could be, after all, life and death consequences for someone later.  If there are mains plugs around that can be inserted into a socket in more ways than one, then they should be removed from sale. That said, I have seen incidences here in the UK with 13A plugs inserted upside down, with the cables exiting the plug at the top rather than the bottom. This was on an industrial floor washer / cleaner, the type used in large department stores by the cleaners, and further investigation revealed the equipment had been badly abused, and the plastic plug top smashed on the floor a few times and the earth pin fell out. With most sockets this would have prevented the plug being inserted, but for a number of years we had a leading manufacturer producing sockets that only required the Live and Neutral pins to operate sockets shutters and thus allowed the plug to be inserted upside down  Given that the machine was a big heavy beast, with a cast alloy body, had a water tank that sprayed the floor in front of it and that the on / off switch was a single pole, it was fatal accident just waiting to happen. I had no option but to report the incident to the store management for them to take further action over it. I have since heard of similar cases back in the day when hand held drills used to metal ones, such names as Black & Decker, Wolf spring to mind.

Think about it, back then there was no such thing as RCB's, even mcb's were usually the domain of industry and commercial building if you were lucky, otherwise it was rewireable or cartridge fuses, and you had completely lost the added safety factor of the PE. Thankfully the maker of those sockets has now replaced them with a range that requires the earth pin to be present otherwise the plug cannot be accidentally inserted.

[cyclin_al]

Buying a used house, the mortgage companies IIRC require a full electrical survey to be carried out before granting any money for the buyer etc. I have done many wiring jobs for homeowners and many industrial ones as well in my working life and I have never come across any sockets that were not correctly wired. All terminals are very clearly labelled as to what they are.

I have never come across outlets wired incorrectly if they were originally done by a sparky. I HAVE come across outlets wired backwards by someone who had no business doing electrical work.

I too have come across outlets wired backwards, but no clue who did it as they were long gone before I arrived. 
They should probably continue to keep their distance from me.

Buying a used house, the mortgage companies IIRC require a full electrical survey to be carried out before granting any money for the buyer etc. Selling a house the law requires that you provide a full current electrical inspection certificate to the buyer. I have done many wiring jobs for homeowners and many industrial ones as well in my working life and I have never come across any sockets that were not correctly wired. All terminals are very clearly labelled as to what they are.

There, fixed a whole bunch of things for you.

Not the same here.  In the GWN, it is buyer beware.  Here, it is necessary to make an offer on a house with conditions.  You arrange your own inspections as potential buyer, and accept the conditions or cancel the deal based on inspection results. 

However, there is a current housing market craze with transactions having no conditions being the only possible chance to acquire a house.  That, and offering ridiculous amounts of money over the asking price.  I am very glad that I am not house shopping at the moment...

[Neomys Sapiens]

Finally - a score.  That spell of bad luck had to end.

I got myself an HP8347A amplifier for under 200.- And more coming up.

[Cerebus]

The fact it is too easy to cut/drill through both conductors and still manage to energize a metal body (especially with the Tim Taylor crowd)

Those are far too small to get the mounting bolts for a V8 on, even for a small block.

[xrunner]

Finally - a score.  That spell of bad luck had to end.

I got myself an HP8347A amplifier for under 200.- And more coming up.

Where's the gozinta and gozoutta? I don't see an option for that on the rear ... 

[Robert763]

...any safe equipment must deal with full mains potential on both conductors of the supply in a way that's no less secure than the "intended orientation".

Issue is moot, and insisting is pointless. IMNSHO.

Mmmokay... how do you make that happen with common household lighting used worldwide with E26 and similar E27 base?

The above near-universal type of lampholder has a propensity for the cardboard insulator to break down with age and/or careless handling by nimrods; this exposes the outer threaded ring of the lampholder to direct contact with the metal shell right where you grab to turn things on/off. This was the primary reason for the NA NEC going to polarized plugs as a standard on small appliances and lighting.

The fact it is too easy to cut/drill through both conductors and still manage to energize a metal body (especially with the Tim Taylor crowd) is why they pressed forward with double-insulated requirement for hand-operated power tools, which later also begat safety lampholders with a plastic body, but these have their own list of weaknesses.

I personally feel that makes a lot of sense, as long as you don't use multiphase power (as opposed to the center-tapped 240VAC system commonly used in NA) for general household stuffs. Which, honestly, I also feel is not a bad idea.

mnem
 

In the UK metal bodied lampholders now have to be earthed, even if they are the UK "norm" of two contact bayonet (B22) base. There are a lot of ES holders in the UK now though.

[Specmaster]

...any safe equipment must deal with full mains potential on both conductors of the supply in a way that's no less secure than the "intended orientation".

Issue is moot, and insisting is pointless. IMNSHO.

Mmmokay... how do you make that happen with common household lighting used worldwide with E26 and similar E27 base?

The above near-universal type of lampholder has a propensity for the cardboard insulator to break down with age and/or careless handling by nimrods; this exposes the outer threaded ring of the lampholder to direct contact with the metal shell right where you grab to turn things on/off. This was the primary reason for the NA NEC going to polarized plugs as a standard on small appliances and lighting.

The fact it is too easy to cut/drill through both conductors and still manage to energize a metal body (especially with the Tim Taylor crowd) is why they pressed forward with double-insulated requirement for hand-operated power tools, which later also begat safety lampholders with a plastic body, but these have their own list of weaknesses.

I personally feel that makes a lot of sense, as long as you don't use multiphase power (as opposed to the center-tapped 240VAC system commonly used in NA) for general household stuffs. Which, honestly, I also feel is not a bad idea.

mnem
 

Also of course with any Edison screw type lamp https://en.wikipedia.org/wiki/Edison_screw the screw thread is one of the contacts to the lamp and so it is vital that the electrician do actually wire things with the correct polarity otherwise, when the lamp blows, and you go to unscrew it, that outer part of the screw is accessible as you unscrew it  Even with the switch in the off position (down for the Merikins), if the wiring is reversed then that screw is live. Yes you should switch off the whole installation, but sometimes that itself is impracticable if you have no other means of providing lighting should this happen after dark. This is why proper testing of the finished installation is important and should be recorded.

[mansaxel]

...any safe equipment must deal with full mains potential on both conductors of the supply in a way that's no less secure than the "intended orientation".

Issue is moot, and insisting is pointless. IMNSHO.

Mmmokay... how do you make that happen with common household lighting used worldwide with E26 and similar E27 base?

The above near-universal type of lampholder has a propensity for the cardboard insulator to break down with age and/or careless handling by nimrods; this exposes the outer threaded ring of the lampholder to direct contact with the metal shell right where you grab to turn things on/off. This was the primary reason for the NA NEC going to polarized plugs as a standard on small appliances and lighting.

I used to joke that North America, the continent sporting mains plugs made from pot metal and paper, could not lecture anyone. But that was a joke. I did not think it was that bad. Until now. Thanks.  That E27 lamp holder is not legal in Sweden, and for a good reason.

Power tools with double insulation, OTOH. That's a good thing.

I personally feel that makes a lot of sense, as long as you don't use multiphase power (as opposed to the center-tapped 240VAC system commonly used in NA) for general household stuffs. Which, honestly, I also feel is not a bad idea.

I happen to use 3-phase power, since my country is the country of ASEA and not the country hailing that con man Edison. His flawed DC mains system has one, and one good thing only: You can get 240V off of it. Sadly, it's not three-phase, but something forcing you poor people  to add capacitors (see rule 9) to every motor.  Our neighbours to the west, the Norwegians, are even purer. They have no neutral, but instead run their Schuko outlets off of two legs from a Delta-connected three-phase grid.

[cyclin_al]

Hooo Boy, I snipped a big one this time (35kg/77lbs) and it's a Fluke! Please remember me to never set auction listing scheduled to end a midnight on a holiday.

Very nice score!  I saw that one, but I have other items higher on the acquisition list and I am not ready to step up my game to that level YET ...

[AVGresponding]

Fuck my old boots, this is going to be a big-ass reply, hope I don't hit the size limit...

Anything that is double insulated, such as a plastic cased drill, fan etc, and does not have any requirement for a ground connection or fuse, should be connected to a plug which is not polarised.

If it connects to the mains, it has to meet BS1363, which means it has to have a BS1362 fuse fitted in the plug-top on the live conductor. Even when it's Class 2 (double insulated).

Always assume previous person was colour blind, normal blind and stupid

And malicious.

With ring topology, one short can take down a dozen outlets/lighting circuits all over a structure.

mnem
tzzzzt.

Lighting circuits are never ring, always radial. Radials are not uncommon for power too, though I hate them, as trying to terminate 2x 4mm² conductors into one terminal is a pain in the arse. Not to mention having to pull 2x 4mm² (or bigger     ) through whatever containment happens to have been specced.

Simple fact: both ring and radial have their pros and cons.

I notice that only the UK socket has safety in mind for the installer as well with shrouded terminals 

I think that is now required, it didn't used to be and I've seen some very sketchy BS1363 wall plates in my time.

It is, and the only belt (well, tingle really) I've ever had was from an old MK multi-gang gridswitch that had multiple feeds. Of course, I didn't realise it had multiple feeds until I got the tingle from the flush terminal screws...

It's because of builders playing electrician (I'm looking at you Roy) that we ended up with "part P" of the building regulations requiring electrical work to be carried out by qualified electricians (strictly speaking by a "competent person").

Now we all want to know who "Roy" is.
The Part P "qualification" is a load of old bollocks; from what I've seen it's mostly used by  heating engineers  plumbers  pipe-fitters and wood-butchers so they can be allowed to wire up the boiler/kitchen they just fitted. It's a very short course (2 or 3 days) and then a yearly "registration fee" of around £700 iirc.



  hopefully I was ruthless enough in the editing to keep the size manageable. Ten new replies since I started though!

[McBryce]

I guess I can't complain too much. The AD584 after 45 minute warm up. It does drift but seems to settle. Documented on the ref at 9.99691V @ 21 C. Currently 26C in here. About 10 minutes later it drifted to 9.99693V

My first thought was "How can you live with such inaccuracy", but then I realised, it's only a 6.5 Digit meter, so it's only an approximation anyway. 

McBryce.

Stirring shite, where there's shite to be stirred

[cyclin_al]

Hooo Boy, I snipped a big one this time (35kg/77lbs) and it's a Fluke! Please remember me to never set an auction listing scheduled to end a midnight on a holiday.

Since my bodge is holding up I did some tesst with my newly acquired Tenma 72-2995.





Nice to be able to generate a AC signal up to 1000V 


It does amps too! 


Overall it look like the calibrator is spot on.

If someone need a 4.5 digits (maybe 5.5digits) multimeter calibrated, let me know 

It's too bad you are across the border of I WOULD be sending you all my stuff to be calibrated.    Nice score and I am blue with envy.   

You can cross the border and visit us now, if you are fully vaccinated.

We are not allowed to go visit you ...

Careful there Kosmic with the offer, I assume I am located even closer than med is.  I may eventually need to calibrate all my stuff, maybe even a reference or two...

[Neomys Sapiens]

Finally - a score.  That spell of bad luck had to end.

I got myself an HP8347A amplifier for under 200.- And more coming up.

Where's the gozinta and gozoutta? I don't see an option for that on the rear ... 

If you are referring to the manual, I am wondering about the same thing. Another device of the same type which was sold had a rear view pictured which read 'Options C01 C04' and was fitted with rear-mounted SMA connectors instead of N. Mine has N, at least they described it as such. And rear-mounted.
So that manual is a bit strange.

[xrunner]

If you are referring to the manual, I am wondering about the same thing. Another device of the same type which was sold had a rear view pictured which read 'Options C01 C04' and was fitted with rear-mounted SMA connectors instead of N. Mine has N, at least they described it as such. And rear-mounted.
So that manual is a bit strange.

Oh I just pulled up the pics on Google, and I didn't see any with rear N, nor did I see any with a place for rear N - just three BNCs for other sigs. Maybe they're out there though. 

If you find a pic with the rear N connectors I'd like to see how they are positioned. 

[med6753]

You can cross the border and visit us now, if you are fully vaccinated.

We are not allowed to go visit you ...

Careful there Kosmic with the offer, I assume I am located even closer than med is.  I may eventually need to calibrate all my stuff, maybe even a reference or two...

Yes, I am fully vaccinated but I still can't visit you fine folks in the GWN. I don't have a passport and I have yet to upgrade my license id to what's called "ESL" so I can cross the border. I've been meaning to upgrade but the Covid shutdown put the stop to that for now. 

[med6753]

So... fuck AWS...?

mnem
 

We haven’t got the bill yet. It’ll be fuck AWS then 

Just survived first day of biggest IT project rollout I’ve had to handhold. Complete success with a couple of minor issues, mostly client self inflicted. But scary shit. 

Food then TE therapy time 

You mean to say the software actually worked the first time? Holy shit, what is the world coming to? 

After 18 months of testing and fixing yes 

Well, pat yourself on the back....but not too hard. 

[capt bullshot]

<snip>
BTW - did you notice the European tester fits both ways into the wall socket. So if it shows "L / N swapped", just turn it around and it'll show OK. Still useful for checking, anyway.

Yes I did notice that, but if you look at the UK tester, it also indicates precisely the same thing. That indicates to me that there is indeed a "correct or recommended" way to wire up your sockets, and that suggests to me that the correct way to use the European tester is with the writing in the correct plan, not upside down.

This is further reinforced by these photos I have found online that shows when looking at the terminal side, the Hot / LIVE should be in the left terminal, NEUTRAL in the right terminal and P/E or GROUND in the middle terminal. That means in a correctly wired installation when looking at the socket installed, from the user perspective, the NEUTRAL is the left hole and the HOT / LIVE is the right hole, exactly as it is for the UK.

I notice that only the UK socket has safety in mind for the installer as well with shrouded terminals 

You can't buy these at a typical home improvement store here (or any other place you'd typically buy wall outlets). The ones you can buy don't have markings for L and N, and you can turn them by 180 degrees with no visible difference. I can remember there was (maybe still is) an unwritten rule to put L to the right hand hole (as you said for UK), but there's no official rule other than "all outlets in an building / installation" should be the same way. There's absolutely no technically based requirement to have polarized plugs, all appliances are made for random polarity input.

[Cerebus]

Now we all want to know who "Roy" is.

That's easy. Roy was a builder I used to know back in the 80s. He failed the same year of his degree in building technology twice (can't remember if it was the first or second year) and dropped out to become a jobbing builder. Had a face like an alcoholic potato. He was too cheap to ever employ a proper electrician, except for industrial work where someone wanted to see a proper NICEIC certificate at the end of it. He used to call on my friend Tony, who I used to sometimes act as "electrician's mate" to, to get him out of the assorted electrical scrapes he got himself into.

One memorable night when we were all having a drink, Roy held forth on how it was a waste of money paying for a sparky when he could do it all himself. Tony, who was there, then spent at least an hour going through the list of jobs he'd rescued from Roy's hands, including all the faults and all the ways that they could have killed someone or burned buildings down. Roy, to his credit, took it in good humour and put his hands up to all of it. However, it didn't mean that he actually changed and either learned how to do it properly or paid someone competent to do it for him.

[Neomys Sapiens]

If you are referring to the manual, I am wondering about the same thing. Another device of the same type which was sold had a rear view pictured which read 'Options C01 C04' and was fitted with rear-mounted SMA connectors instead of N. Mine has N, at least they described it as such. And rear-mounted.
So that manual is a bit strange.

Oh I just pulled up the pics on Google, and I didn't see any with rear N, nor did I see any with a place for rear N - just three BNCs for other sigs. Maybe they're out there though. 

If you find a pic with the rear N connectors I'd like to see how they are positioned. 

Seeing those oversized SMA adaptors, I assume that the N jacks will be in the same place. But I'll post a pic when it arrives. Maybe I will convert it to front anyway.

And it fits what I came to expect from HP manuals.