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Ah those Tourists ...   :)   
They always come along with their home appliances with out thinking wall plugs EU compatibility.

Especially local computers repairs stores, now owning last amount of BS1363 UK power plugs (NEW) because the customer replaced the cable by getting THE compatible version.

Few months ago I thought the possibility of using the large brass (Earth) pin in to another project,  last day I asked few friends of my about free of charge stock of such BS1363 and I got plenty.
One of them this is open-type and you may replace the cable, I will name this as golden standard and I will keep it as is.

The many... will be driven to grinding wheel, the plastic near to ground pin this get partially removed, plastic gets warm due friction and the pin can be then extracted.
Here are few pictures for you to see   :)   

My project of how to reuse such brass pins this is another story, for a later time.  ;)

Here is few thoughts for the ones thinking to activate temperature protection.
You are going to need a switch thermostat, normally closed contacts.
They are many selections available speaking of temperatures range.
You better consult manufacturer documentation so your choice to really get triggered at your choice of Max temperature.

Another thought that it should puzzle your head, this is what you are thinking to protect?
The switch thermostat is rather slow, this is not for measuring the temperature of a single battery cell.
Such a switch thermostat, this is more an fuse with self recovery action, it might help protecting and air-tight battery pack in which the BMS this is stuffed in it.

My own first thought this is that for my application I do not need such a thermostat.
If I was using this battery with a high drain device then I would worry so the power MosFet to never get very hot, because the heat eventually will be shared at the lithium cells, and entire battery pack it would turn to an oven.
Soon I will perform a test, so to discover quantity of heat and temperature dissipation according to Load.
This thing has MosFet in the casing of IC, such things brings to me memories from the era that I was placing miniature heatsink over my VGA card so to overclock the speed of RAM chips.  ;D

Here is a picture of such switch thermostat, less than 1 USD on eBay.       
Transit (11Days) from China and delivery by the postman at my door ... this is a wild dream but it did happen.  ;D

Now I am forced to wait for the special lithium battery holder boxes. 
On a second thought, a half-damaged BNC plug this is a serious downfall at any CH (1,2,3,4), you can not use any more a regular coaxial cable so to perform DC Offset calibration routine at GDS 2000A series (software - hardware controlled process).  :P


Sorry for problem with your scope, it's hard to find original parts for such professional tools as you have. You can opt for a compromise solution until you find the original piece or at least one replacement for it. If you do not use the EXT. TRIG. entry you can replace them for the moment. Or you can get one on the back of the device (CAL. or OPEN COLLECTOR entry).
I hope my idea is not a bad or destructive one for you.

My first though this was also, about swapping one of the many BNC plugs (Gen1 / Gen2) with the CH1.
Digikey (USA) wants 18 Euro just for shipping of two new BNC, total cost about 30 Euro.

My scope this is six years old, back then GW Instek was very helpful regarding delivering spare parts, I got for example a spare soft-keypad (entire set of silicon push buttons).
Nowadays I wish to see how they will respond regarding soldered parts.
Bench-top Oscilloscope / Re: GW Instek GDS-2000A - BNC Oscilloscope plug damage
« Last post by cluca1969 on June 24, 2019, 07:06:50 PM »
Sorry for problem with your scope, it's hard to find original parts for such professional tools as you have. You can opt for a compromise solution until you find the original piece or at least one replacement for it. If you do not use the EXT. TRIG. entry you can replace them for the moment. Or you can get one on the back of the device (CAL. or OPEN COLLECTOR entry).
I hope my idea is not a bad or destructive one for you.
Bench-top Oscilloscope / GW Instek GDS-2000A - BNC Oscilloscope plug damage
« Last post by Kiriakos GR on June 24, 2019, 12:34:48 PM »
My GDS-2102A this is now 6 years plus three months old.
This is two channels version,  and as expected I am frequently using CH1,  over the years I did performed no more than 100 mating cycles at CH1, and about less than 15 at CH2.

Yesterday I did try to plug-in a regular BNC male connector and I discovered an issue, center pin does not make any contact.
Then I did try Amphenol BNC,  MC Multi-contact BNC,  MIL type male BNC, non of them works other than the BNC of the oscilloscope probe.

Now I am convinced that CH1 female BNC this must and should be replaced.

I did contact GW Instek in Taiwan and waiting for their response.

Then I started a product search over search engines and after an hour I did found the proper spare part, this is Amphenol 31-5633.
Alternative branded equivalent this is TE Connectivity (Tyco brand) 5227673-1  

GDS-2102A BNC connectors they do not have any branding / markings, I am now assuming that these are local production of Taiwan from a source that GW Instek works with.
My CH1 BNC connector has intact all four contact pins, but the damaged area looks to be further inside than what a naked eye can see.

I am look after my scope as to were a treasure, so BNC plug misuse this is out of the question.
What I am currently suspect this is the oscilloscope probe connector center pin, this seems wider than other male BNC pins and for this reason still makes a contact.
From the other hand I an puzzled to decide if this detail is the smoking gun which caused premature failure at the female BNC?

For now I am going to post a few pictures, and I will post more details as soon I will get more information about alternative paths that I can follow so to get in hand relative spare parts.
This is going to be an out of warranty repair.  :)


If the newborn Chinese sellers think them self’s as Masters of DELUSION then I am their Exorcist and the Angel responsible for their punishment.

This story it is about the exotic gold and equal to treasure 10A plain garbage Kelvin Clip.

The father of this poorly made clip this is one hidden factory in China which this also selling an old school milliohm meter, the one for wires verification only and not for measuring resistors,  this is why this using 10A as current source.

Ebay sellers in China found this poorly machined clip as great opportunity to steal the money of dump ass westerns.

They offer Oversized pictures, shiny gold paint, and lots of gifts including FREE of charge heat shrink tubes. 
True value of a pair of those clips this is half American dollar, if this is truly made of brass.

Mechanical construction this is poor speaking of geometry they are full of harsh corners at the point in which the round plastic will join them together.
The construction of the jaws this is poor too, it is obvious that they melt the metal in to a cast.
Final addition this is a piece of silicone tube which will create tension.   

Most of other pictures as this looking assembled with wires they are also a plain joke.
If you do solder wires under the handle the clip this is unable to work.
Therefore the only reasonable though this is connecting the wires at the top of the handles.
The ideal wires connection scenario this would be crimped wire over the brass, but such product design this is expensive as it does require smart people and they are costly so to hire them.  :P
I think the most important thing of the clips is that the contact surface to be much stronger as possible.

Your thinking this is correct, an flexible contact surface will sabotage Kelvin clips Zero calibration.
ITTSB Blog readers they should have a look also at this article.
Topic: Kelvin clips and cables maximum length ? & Other tips by ITTSB Blog

This weekend I send two proposals, one to an Asian T&M brand  and a second to a German brand and maker of Kelvin Clips, so ITTSB Blog to obtain product samples for testing.  ;)

By searching to discover how many Kelvin clips ODM sources they are out there? 
I came across to a schematic this pointing out THE proper way for Kelvin clips Zero calibration.
I did try this recommendation at my Fluke 8846A and it did not work at all, this recommendation comes from a manufacturer of milliohm meter from the ones using high current up to 1A at 100 milliohm range.

Kelvin Clips this is an accessory that it serves three different types of equipment.
a)  Kelvin Clips for LCR (ACV test signal)
b)  Kelvin Clips for Resistance - Multimeter circuit – DCV with 5mA Low current source.
c)  Kelvin Clips for milliohm meter dedicated to measure wire resistance and not electronic components.
The meters can use 1A or 10A as source so these to measure at their lowest range of 2 or 20 milliohm.

In summary, they are three different electronic circuit architectures’ all of them using Kelvin clip accessories.
Now let’s leave aside the LCR meters in which Zero calibration this is more foolproof.

For precision resistance measurements’ it is important Kelvin clips to be manufactured in a way that bottom and top copper surface of a single contact point to not be flat.
Most Kelvin clips have a slippery top surface (sanded – polished metal) in which when we try to Zero our Kelvin clips they can not stay stable and unmovable.
My work around this is laying them flat over my workbench, holding them and their cables too for 20 seconds (EMF elimination) and then to use Zero Math at my multimeter.

Another detail which Kelvin clip manufacturers do not pay much of attention, this is mechanical tension force when clips are closed.
When a Kelvin clip has low mechanical tension force when closed, this force will be unsatisfactory also when we perform Zero Calibration, and this translates to unseen issue which can negatively influence our measurement.
Identical problems can occur when Kelvin clip copper surface this is thin and flexible.
Copper it self this is soft, usually thin layer of below 1.00mm of thickness this is brass alloy which this will also flex under some pressure.
Now I am thinking than 3.0 mm of thickness of brass alloy, this is the only one that we can trust for using Kelvin clip at large amount of applications other than measuring a resistor component.
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