Wednesday, 6 January 2016

DER EE DE-5000 LCR Meter Kelvin Clip Conversion Hack

I recently purchased a DER EE DE-5000 LCR meter, these are well regarded and inexpensive meters made in Taiwan. The unit i purchased was supplied with the TL-21 test leads that plug into the banana sockets and test ports to provide easy to use clips for testing components.

Although the meter is great i was a little disappointed with the test leads, although they are kelvin to the crocodile clip they are very short and dont supply a proper kelvin connection to the component. The two connections are terminated at the solder point on the crocodile clip. So i wanted to change this so i had some proper kelvin probes which had longer wires and easier to use clips.

I was not looking for the ultimate in performance, but just to improve the usability and performance for a reasonable price so i chose to buy a cheap set of kelvin clips off ebay, these cost about £10 including shipping from china. The set i bought was supplied with BNC connectors and coax. This i thought should be ideal for retrofitting into the existing TL-21.

The kelvin clips i bought from ebay.

On opening the DER EE TL-21 test leads, i was pleasantly surprised to find 4 wires running to the crocodile clips and the guard/screen in place which meant converting them with the cheap kelvin clips a simple task.

The BNC connectors were chopped off the new clips and the cable shortened to about 30cm, these were simply soldered in place of the original clips.

After running the calibration (zeroing) procedure on the meter with the new leads, shorting the clips shows 0.00 ohms, it's a shame DER EE dont offer these as an accessory.