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BS2 Voltmeter — Parallax Forums

BS2 Voltmeter

piguy101piguy101 Posts: 248
edited 2015-01-21 12:56 in BASIC Stamp
Howdy all. I have been designing a switch mode benchtop power supply and am in need of some way to display the voltage and amperage. I have seen built solutions such as Adafruit's volt meter http://www.adafruit.com/product/705, but I was looking to do so with an extra BS2 lying around. Would the MCP3202 http://parallax.com/product/604-00060 be a reasonable choice to use to interface with the BS2 and then convert the number to a voltage or is there a better way?

Comments

  • Chris SavageChris Savage Parallax Engineering Posts: 14,406
    edited 2015-01-20 17:01
    The MCP3202 could be used. One channel could measure voltage and the other, current. However, depending on the voltage range of the supply you may need to scale the voltage going into the ADC as the max voltage shouldn't be more than 5 VDC.
  • piguy101piguy101 Posts: 248
    edited 2015-01-20 18:49
    Thanks for the confirmation. Of course I plan to use a voltage divider to reduce the voltage and an op amp to boost the voltage over the shunt.
  • ercoerco Posts: 20,257
    edited 2015-01-21 08:49
    Or save the BS2 for a cool robot controller and get an assembled VA for $3.41. :)

    http://www.ebay.com/itm/DC-4-5-30V-0-50A-Dual-LED-Digital-Volt-meter-Ammeter-Voltage-AMP-Power-ES9P-HG-/281544934745

    Seriously, it's a great learning experience to do your project as described with BS2 and ADC.

    But for $3, buy one as a backup. I'm amazed that anyone would bother creating something to be sold so cheap, assembled and ready to go.

    Kick the tires, light the fires and aviate!
  • piguy101piguy101 Posts: 248
    edited 2015-01-21 10:18
    erco wrote: »
    Or save the BS2 for a cool robot controller and get an assembled VA for $3.41. :)
    It's too bad that doesn't read any voltages less than 4.5V. With that price, I might have to get one just as a backup though.
  • RDL2004RDL2004 Posts: 2,554
    edited 2015-01-21 12:56
    Most of those cheap volt and amp meters can read down to zero. The 4.5-30 volts is the power supply voltage range you can use to power them.
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