Circuitbenders Forum

Please login or register.

Login with username, password and session length
Advanced search  

News:

Author Topic: voltage divider - smoking potentiometer  (Read 6395 times)

wax+wire

  • Dayglo Volunteer of International Masturbation
  • ***
  • Karma: 0
  • Offline Offline
  • Posts: 113
voltage divider - smoking potentiometer
« on: September 08, 2014, 08:34:18 AM »

Sometimes when i build a voltage divider/drop type thing (dying battery simulator or similar)  i burn my pot straight away.

i set it up like this:::

lug A = voltage in
lug B = voltage out
lub C = ground

it makes sense to me if voltage goes from A -to- C it is going to smoke and fizzle... what am i doing wrong?

ps. just was doing this as the cut-off in Graham's filter
Logged

Circuitbenders

  • crustypaul
  • Admin
  • This person is dangerously insane.
  • *****
  • Karma: 1102
  • Offline Offline
  • Posts: 2451
    • Circuitbenders.co.uk
Re: voltage divider - smoking potentiometer
« Reply #1 on: September 09, 2014, 12:56:53 AM »

You're trying to put too much current through the pot.

At the lower resistance end of its rotation it won't be able to take it and will burn the carbon off the track.
Logged
i am not paid to listen to this drivel, you are a terminal fool

Circuitbenders

  • crustypaul
  • Admin
  • This person is dangerously insane.
  • *****
  • Karma: 1102
  • Offline Offline
  • Posts: 2451
    • Circuitbenders.co.uk
Logged
i am not paid to listen to this drivel, you are a terminal fool

wax+wire

  • Dayglo Volunteer of International Masturbation
  • ***
  • Karma: 0
  • Offline Offline
  • Posts: 113
Re: voltage divider - smoking potentiometer
« Reply #3 on: September 09, 2014, 01:28:50 PM »

so part of my problem might be using a powersupply so there is too much current flow?  should i try a battery?

or put a resister in series with the ground to limit the voltage drop so it never sends all the current to the ground?
Logged