24VAC motor driver

Discussion in 'General Electronics Chat' started by viveiroscordeiro, Jan 29, 2015.

  1. viveiroscordeiro

    Thread Starter New Member

    Aug 20, 2012
    I would like to drive a small Electric motor, from batteries (24VAC timer motor). It's from one of this domestic mechanical timers. The motor is original connected with a resistor directly to 220VAC. As it makes 1 turn in 24H, is perfect for time-lapse photography, but I need to drive it from batteries... Is there a relatively simple manner to do that? Tanks for any help.
  2. GopherT

    AAC Fanatic!

    Nov 23, 2012
    It might be easiest to buy a small 12VDC to AC inverter used in cars/trucks. A 3-cell lithium polymer battery will supply plenty of power.

  3. Reloadron

    Active Member

    Jan 15, 2015
    I just use one of these I picked up from a local camera store for about $20 USD. They make them for a wide range of cameras and the one I have has about 6 timing modes. I also use a remote shutter release but this little timer is great for photography. The one I have is for my Canon EOS 7D but they come in many versions for many cameras.

    Per GopherT you can also get an inverter. Just keep in mind that the little motor in the timer you have uses a synchronous AC motor so timing is a direct function of the line frequency. Also, there are several types of inverters, most inexpensive units output a "Modified Sine Wave" which can be a problem for synchronous AC motors, so if you use an inverter I sugest one with a true sine wave output which can be expensive.

  4. KeepItSimpleStupid

    Well-Known Member

    Mar 4, 2014
    The OP likely has a typo 24 VAC is really 240 VAC. and as Ron implies, there is usually a cap across tow wires. Power get applied to the common and one end of the cap depending on direction.

    about 20 years or more, I scribbled a circuit made from a 555 timer and a center-tapped transformer acting in reverse so he could do some celestial tracking. Worked like a champ.

    faster means higher frequency.
  5. MaxHeadRoom


    Jul 18, 2013
    I have never seen a cap across appliance timer motors, they are synchronous motors, run at the frequency of the supply.
    Like clock motors, they have a spring kick start for direction if not they can start up in either direction.
    The 240v models in N.A. are usually for appliances such as dryers that only have 240v supply.
  6. viveiroscordeiro

    Thread Starter New Member

    Aug 20, 2012
    Thanks, but the motor is not to use like a timer, I already have one in my Canon, the "Magic Lantern", and the GoPro as one built in it to.
    The motor was to produce motion, as it makes a turn in 24H is perfect to track the stars... I allredy test it, but would be nicer to be free, from de power cable. I was thinking if there is any simple circuit to modulate 24VDC in 24VAC 60Hz ... Or I may use anode motor to connect to the gear box and try to adjust the speed...
  7. MaxHeadRoom


    Jul 18, 2013