I have an old poptronix esr meter I use often. it can be used in circuit because the injected signal is around 200mV and does not interfere with semiconductors on the board.
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if you can measure capacitance with such a small signal it would be ok then
I also have a recent deree de5000 lcr meter, and I can measure capacitance and esr in circuit with it because the test signal is small also around 500mV.
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you are limited to the fact that if capacitors are in parallel, you will measure the total capacitance, and this if-s often the case inside power supplies. if one capacitor only is bad, you won't be able to find it without desoldering.