What is it?

To connect kelvin (4 wires) probes to an handheld LCR some kind of adapter is necessary. The adapter allows to reach the contacts inside the instrument slots used to insert the tested component leads.

User Voltlog designed a very nice adapter pcb for Hantek LCR meters, it can be bought on tindie.

I derived from his project a version suitable for other LCR models. I have also foreseen the way to mount the capacitors necessary for measurements on batteries.

The LCR adapter PCB is designed for theese LCR models:

• MCP BR2832
• B&K Precision 878B / 879B / 880
• Tonghui TH2822A / TH2822C / TH2822D / TH2822E
• Eucol U822,
• Sourcetronic ST2822/ST2822A/ST2822C

I have no information regarding other models. You can chek compatibility to your model by comparing your LCR adapter/slots with the provided dimesions and pad signal description. PCB thickness is 1.2 mm. Please note that some handheld LCR does not provide 4 wires measurements. An example is the Keysight U1730C series.

Use for battery measurements

When using probes to measure battery internal resistance or impedance with the LCR, it is necessary to insulate the instrument from the battery voltage to avoid damaging the LCR. The PCB allow mounting of 2 electrolitic capacitors to perform this insulation. Suggested values: C1=470uF, C2=2.2 uF. When capacitor are not installed the pads shall be short-circuited.