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Measuring voltage and capacitance of capacitors in parallel? how do?

  1. Oct 20, 2014 #1
    im hooking up 6 450v 10000uf capacitors in parallel for an exparement for school (under supervision of my professor) he wont tell me how to monitor these devices and how to know when they are full and when to release them.
    does anyone think they could give me a quick and dirty answer?
    Last edited: Oct 20, 2014
  2. jcsd
  3. Oct 20, 2014 #2


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    Uh ... what is a 450v 10000v cap ? ONE of those "v"s has got to be wrong.
  4. Oct 20, 2014 #3
    sorry i missed that it should by 450v and 10000uf each
  5. Oct 20, 2014 #4


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    What do you know about charging capacitors?
    What measurable property/s of the circuit will change once the caps are charged?
    Can you use a multimeter to measure those property/s?
  6. Oct 20, 2014 #5
    450V,10000 μF must be an electrolytic cap. Watch out for polarity of these
  7. Oct 21, 2014 #6


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    I hope you teacher has been thorough in the health and safety instructions he's given you. There's a lot of energy (lethal) in one of those capacitors, when charged. (Can you calculate it?) Also, discharging one through a short circuit could damage it.
    Before we go any further, it would be useful to know your level of education and expertise - or we could be talking well above or below that level.
  8. Oct 21, 2014 #7
    The down and dirty ( and relativity safe) is to make a voltage divider(I would throw in a fuse for good measure - no pun intended). -- You should not be applying a meter to this assembly manually, there is too much energy there.

    You can also buy a DC voltage transducer - that would provide isolation. ( PhoenixContact has one for ~$600)

    What you will find in this type of assembly is the parts are relatively simple and inexpensive - however the interface, control and monitoring costs are high.
  9. Oct 22, 2014 #8


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    Beware.. the capacitors might be charged already.
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