Sit/Stand table Power source help

Discussion in 'The Projects Forum' started by Dima Abramov, Sep 28, 2015.

  1. Dima Abramov

    Thread Starter New Member

    Sep 24, 2015
    3
    0
    I bought a non working Ikea sit stand table. Which had a problem with one of the encoder wheels which messed up electronic logic part, and so far i cant find a way to reset it. So in a mean time i just made my own logic using arduino and relays while trying to figure out original system. Here comes a problem
    Motors rated at 24 v 5 amp nominal and 20 amps stall. the original power supply that came with table is 35v 2.1a so they use PWM to drop the voltage down and maybe even use it in shifted phase (pwm ON overlap is minimal between 2 motors). Floor model in Ikea feels strong.

    The best power supply i could find was 19v 6.3 amp, the table pulls weak and putting some weight trips overcurent protection on PSU. So here are my questions:

    1. I have found 24v 4.3 amp supply on ebay, will it improve the torqu of the motors due higher voltage, or decrease it because of fewer amps (also WATS are a bit less).
    2. i have a UPS unit that has 24v battery, i want to power table up from the battery directly (fusing it for safety of course), i don't think this will affect UPS itself but i am not a specialist! So IS it safe for UPS to have a table draw power directly from table? (i don't expect to change table positions more then 2-3 times a day) !
     
  2. Alec_t

    AAC Fanatic!

    Sep 17, 2013
    5,801
    1,105
    1) A 24V 4.3A supply is inadequate for a 24V motor drawing 5A nominal and 20A peak.
    2)
    Eh? :confused:
     
  3. Dima Abramov

    Thread Starter New Member

    Sep 24, 2015
    3
    0
    1) yea i understand that but then,but i dont uderstand how did IKEA managed to run the table of 35v 2.1 amp PSU?

    2) What i meant UPS stays intact and works as UPS. I tap to battery terminals to draw 24v from UPS battery to run table. The charge lost in battery will be restored by UPS.
     
  4. Dima Abramov

    Thread Starter New Member

    Sep 24, 2015
    3
    0
    Anyone?
    Is it possible for same motor same load to consume lets say 120w at 19v and 100w at 24v ?
     
  5. GopherT

    AAC Fanatic!

    Nov 23, 2012
    6,061
    3,823
Loading...