Trimming Potentiometers, how long they last?

Discussion in 'General Electronics Chat' started by secretstep, Aug 2, 2008.

  1. secretstep

    Thread Starter Member

    Jun 27, 2008
    How long do Bourns Trimming potentiometers, such as 3306, 3352, 3362 and 3386 last?

    I looked at the data sheet, and on the "environmental characteristics", it says...

    Load Life ..1,000 hours 0.5 watt @ 70 °C
    (3 % ΔTR; 1 % or 1 ohm,
    whichever is greater, CRV)
    Rotational Life ........................200 cycles
    (4 % ΔTR; 1 % or 1 ohm,

    Does this mean that if I use potentiometers for around 200 cycles, turning it clockwise and back, doing it 200 times, then the trimming potentiometers do not function anymore or break down?

    These trimming potentiometers I mentioned are designed in the way I want to use. However, I like them to work for more than 10000 cycles minimum.

    Can anyone please specify how to translate this data sheet?

    Thanks for help.
  2. jpanhalt

    AAC Fanatic!

    Jan 18, 2008
    They will last more than 200 rotations, but they definitely are not intended for multiple adjustments in great excess of that . You will notice that they get noisy or that it is hard to get a good adjustment when they wear out. That's why they are cheaper. For 10K cycles, you are best off buying a real pot.

  3. SgtWookie


    Jul 17, 2007
    Trim pots are usually adjusted seldomly; only when necessary as during a calibration cycle.

    If you need to adjust something more frequently than that, explore using digital potentiometers, or a panel-mount pot that's designed for such high use.

    Or buy extra, and keep your soldering iron handy.