One for the books - or gamblers.
One for the books - or gamblers.
(OP)
Here is a schematic I am to assemble. The author of this misbegotten rag is gone and hopefully the fish enjoyed his company and fine corals are living on his cement shoes..
Here is today's problem:

The capacitance meter is a high end Fluke unit that uses 1kHz, 10kHz, or 100kHz to figure out the R, L, and C.
The 'device' is just a crummy quality capacitor with about 0.010uF of capacitance.
I appears to me that the bottom three elements do nothing.
Can anyone suggest if this circuit does anything I'm not seeing?
Keeping in mind that other things on this schematic were blatantly wrong that I've sorted out, can you suggest a logical "correct" connection to the test device?
Here is today's problem:
The capacitance meter is a high end Fluke unit that uses 1kHz, 10kHz, or 100kHz to figure out the R, L, and C.
The 'device' is just a crummy quality capacitor with about 0.010uF of capacitance.
I appears to me that the bottom three elements do nothing.
Can anyone suggest if this circuit does anything I'm not seeing?
Keeping in mind that other things on this schematic were blatantly wrong that I've sorted out, can you suggest a logical "correct" connection to the test device?
Keith Cress
kcress - http://www.flaminsystems.com





RE: One for the books - or gamblers.
TTFN
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RE: One for the books - or gamblers.
From power basics, the phase angle of the test current will be changed by the relative currents through the resistors and the capacitors.
You can replace the circuit with one 0.01 uF with double the voltage rating, shunted by a 2 m Ohm resistor.
Is the intent to test capacitors so tiny that they may be damaged by the test current or voltage of the fluke? If so, this may be an attempt to design a voltage divider.
Please let us know how the circuit responds under test!
Bill
--------------------
"Why not the best?"
Jimmy Carter
RE: One for the books - or gamblers.
LOL - perhaps they're spares - LOL.
RE: One for the books - or gamblers.
Bill
--------------------
"Why not the best?"
Jimmy Carter
RE: One for the books - or gamblers.
Yeah I just glanced at this circuit and bought the parts. Now soldering iron in hand, I stare dumbly at what is before me.(that I missed)
I think IR may be correct. These are supposed to be two sets - one in each lead of the test circuit. The ugly part is that that requires two drafting errors instead of just one. That vertical line needs to go away and the top line needs to have the top set in it. (actually three errors then!)
The capacitor under test will first have had 5kV across it. The FLuke can have only 40V into it. Perhaps the 10M ohm resistors are to protect the Fluke even though there is a discharge position that is supposed to isolate and discharge the cap-under-test before reaching the Fluke testing mode.
<sigh>
I will be trying that first. Luckily they've given me test data to show what value they expect to get.
Keith Cress
kcress - http://www.flaminsystems.com
RE: One for the books - or gamblers.
So unless there's an B-A mode, the measurement would be contaminated by the extra capacitors.
TTFN
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