As many of you know, Franky on here sells a DIY Kelvin clip kit. After some waffling I decided to try his most recent iteration of this kit and I must say I am thoroughly impressed. He has a winner of a kit for sure.
Contents of the kit:
- 4x Banana plugs - 2x red, 2x black.
- 1.2m of red 14AWG silicone wire
- 1.2m of black 14AWG silicone wire
- 2x updated Kelvin clips
- Red and Black high quality heat shrink
I opted for the stackable banana plugs, though in hindsight I should have gone with the standard shrouded like he originally offered. The stackable plugs are great for individual cables but make no sense here.
The kelvin clips are made by ETA (Electronic Test Accesories) Taiwan and appear to be the same ones used by GWInstek for their LCR leads. These clips feel VERY nice, they are very solid and have a nice spring to hold them together. They grip the DUT nice and tight, without any problem of slipping. The wire connect can easily detach from the body by the removal of a single screw. This makes it VERY easy to solder a very reliable connection without damaging the plastic body of the clip. The quality of the everything feels very good and comes together nice and tight when fully assembled.
Cutting the wire to length; each color was cut to two wires of 60cm length. The cable has a nice soft silicone shell and is VERY flexible.
Stripping off 5mm of the outer silicone jacket, I was really surprised at the number of strands in this wire. This high number of strands, combined with the soft silicone shell mean this is a very flexible wire which is easy to work with. Another thing to note, unlike most discount Chinese wire there is a solid amount of metal in the wire. I am unsure if the wire is tinned copper, tinned steel or aluminum.
EDIT: It is very clearly tinned copper, see the end of the post for the evidence.Stripping 5mm is basically perfect for inserting into the banana plugs.
Stripping 2-3mm off of the other end is perfect to fit into the connector to the Kelvin clip. The 14AWG wire is absolutely a perfect fit for these connectors. Sorry for the blurry photo, unfortunately, I didn't realize it was blurry until I started typing.
A quick comparison of cheap solder (red) versus Kester 44 (black). Both are supposedly 63/37 solder but it is clear they aren't even close to the same quality. I ended up removing the solder from the cheap one and applying fresh Kester 44.
Cutting a bit of heatshrink to cover the connector. This heatshrink really shrinks down, much more than most of the cheap heatshrink I have encountered. Additionally, when it shrinks down it gets a lot more firm, to the point it serves as a kind of strain relief.
Trimming the heatshrink back to the camfered edge to allow it to properly fit into kelvin adapter.
Putting it all together, large screws attach the connector to the kelvin clip.
The screw covers, a very nice touch. There is one for High Force, High Sense, Low Force and Low Sense.
Now the most important part, how does it work! Very well, my meter fluctuates between 0.1 and 0.4 mOhm when shorted. Additionally, a precision 294K resistor reads exactly 294.00K. I have NO clue why the images look so compressed, a recent update to my phone really messed up the digital camera it seems.
As I said before, I am REALLY damn happy with these. Especially when you consider the price! The whole kit was cheaper than just the clips on ebay. Also, shipping from Hong Kong only took one week, three days of which the package was sitting in New York waiting to be shipped to my region.
Edit: I dissolved a small spare portion of the wire in concentrated sulfuric acid so far only the outer tinning has dissolved. It appears to be copper underneath. So the wire is tinned copper.