Quality Kelvin Clip - Sudden DEATH story

[Kiriakos GR]

One picture = 1000 words.
But what us consumers we are not informed about this is life-cycle of plastic materials in use for test-leads. 

Some factories they deliberately create plastics with limited life-cycle by thinking GREEN, but some others they simply make plastics which will shortly decompose and collapse, so to force consumers spending further more money about buying this product again and again.

A third case of premature death of Kelvin Clips, this is forcing the clamp jaws beyond their mechanical ability (Jaws full open).
A fourth case, this is stepping over it with your shoe.     


I am not a fortune teller, I do not know what happened with specific (HP / Agilent 16089B) clip, but beware to not stressing your Kelvin Clips. 
Naturally I am all ears and eyes for your own Kelvin Clip - Sudden DEATH story (if you have one to share).
     

[cluca1969]

I have a set of Kelvin probes for over 25 years, they come from an old HAMEG benchtop. Looks pretty good, the only change I brought was that I added some O-rings over the original rubber to strengthen the jaw contact pressure. I was going to buy some new ones but after this change I decided to keep them. I searched them on the net and found them like:
Pomona 5940 - Kelvin Clip Cable Test Lead Set and KEYSIGHT 11059A Kelvin probe set.

[Kiriakos GR]

I have use KEYSIGHT 11059A just once.
I disliked the wires, they seem hard and their isolation seemed to be made of hard nylon.

One customer of my, he got those for a Fluke 8846A in my city, the fifth banana this has no actual use at 8846A, if shielding this required for very high ohm measurement then 8846A USB port ground (metal frame) this is the only plug-able section that some one can use. 

Speaking of favorites, this is my favorite cables which I will never buy due their salty pricing.

[cluca1969]

Maybe you are right about the wires from KEYSIGHT 11059A but mine they are really very flexible and I strongly believe that they are Pomona 5940 and from pictures seem to look better, do not give you the impression of silicone cables but are very flexible.

[Kiriakos GR]

I am assuming that KEYSIGHT 11059A which I did touch they are production of 2015 or so.
It seems that they are out there several products of different batch (small changes at its revision).

My problem this is build quality of the clip and longevity this is warranted when they are spring loaded instead using O-rings.
Spesific HIOKI Kelvin clips they have clips design which I think that I can trust for non-flat surfaces.
About specific HIOKI cables softness I have no idea.

[cluca1969]

I think the most important thing of the clips is that the contact surface to be much stronger as possible.
And you what kind of clips use for your HIOKI ?

[Kiriakos GR]

RM3542A this using a Kelvin Clip harness with BNC end point, part code HIOKI 9140-10.
 
The plastic body of the clip started to crack at the jaws, I am keeping these alive by adding super glue at both clips.
They must be replaced in the upcoming months.
This harness it is also overpriced, I am now looking for another solution to improvise by replacing the plastic clip body by retaining clips jaws and cables as is.
Still looking for a solution.

Kelvin clips known as Taiwanese origin (GW Instek) GTL-108A they are good but not great, they seem slippery because their inner grooves at the jaws they are close to be called as flat and top jaws surface this seems as polished and it is not flat and uniform. 

[Kiriakos GR]

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. 

   

[Kiriakos GR]

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. 

[Kiriakos GR]

Agilent 16089A this is Kelvin clip harness from the most rare ones speaking regarding product design.
Major advantage this is Kelvin clips jaws which can serve for flat and non flat surfaces.

This harness is now a very old product, and product pricing as used even this is still extreme.
I am simply posting these pictures for educational purposes. 

[Kiriakos GR]

Actually this is not upgrade from GTL-108A to GBM-01, GW Instek got in to battery resistance testers manufacturing at 2018, and they needed something better than an LCR clip for small diameter components.
New GBM-01 cable harness this using newer production clip, which this currently seems unavailable as solo Kelvin clip for DIY.

Mechanical pattern over jaws (teeth) this is identical to HIOKI L2101 cable harness for their own battery resistance testers.

Now here there is an issue,  battery resistance testers all using PULSE signal and not DC current and therefore they do not care of EMF which is an issue for regular bench top multimeter.
GBM-01 price point this is under 100 EUR mark, but still not recommended as Kelvin clip for bench top multimeter.
 
 
   

[Kiriakos GR]

Under the microscope of ITTSB Blog this time it is BK Precision TLDK1 4-Wire Kelvin Test Leads.

This is another Kelvin clip designed to serve as battery tester accessory.
I did a special request to a friend for a close up picture speaking of grip potentials over the body of panel mount banana plug. 
He reported that grip performance this is sufficient.

.....................................................................................
ITTSB Blog comments :
a) The Jaws seem poorly machined (curved) in contrast to HIOKI and GW Instek equivalent clips.
My impression after visual inspection of several pictures,  this is regarding machinist work over jaws,  Top rank position goes to HIOKI, second best GW Instek and third this goes to BK Precision TLDK1 Kelvin clip.

b) Alligator clip force seems quit good (spring power).

c) Its Jaw height seems larger than Kelvin clips for components testing, I am now up to discover if TLDK1 this is capable to get and hold center pin of a male BNC assembled plug?
This answer came fast to me, this battery clip almost has a touchdown but not perfect landing over the pin body ( it simply touches pin front point).   

d) BK Precision TLDK1 pricing this is the friendlier so far, this is 45~50 EUR retail (Tax included).