Agilent 1732C strange on Mohms

[Andrejka]

Hello,

Question for someone who owns Agilent U1700 series LCR meter.
This is is fault or normal behavior, when nothing is connected meter still shows in R mode around 100 megaohms resistance.



Thanks

Andrej

[mr.fabe]

I tried replicating your settings on a Keysight U1733C and this is what I get...

[Per Hansson]

On my U1733C if I have the crocodile clips connected like you it hunts between KΩ and MΩ
But if I remove the leads it shows 0.L
Or if I connect the SMD tweezers it also shows 0.L
I assume the reading is from capacitive coupling to the unshielded cables?

[Andrejka]

I have 10Mohm 0,1% precision resistor, while on Fluke is stable 10,00 reading, on Agilent is 9,21 and very slowly increasing. Resistor was inserted directly to meter's socket. When nothing connected - reading's  floating between 180 - 199 Mohm.
Something is damaged?





Thanks

[Per Hansson]

Yes that is not good, maybe something is damaged or it could be as simple as PCB contamination.
I.e. cleaning the PCB might fix it if it looks dirty of flux or anything foreign that has went inside...

[rodpp]

In my U1733C it is erratic, sometimes it displays OL, sometimes floating around 5M.

There is a frequency correlation, if it is set to 100Hz or 120Hz it always display OL. If set to 1KHz or 10KHz, it displays some Mohms. And the readings on the 10KHz are lower than on the 1KHz.

At 100KHz there is no Mohm measurements.