Connect with us

DC voltage regulator

Discussion in 'General Electronics Discussion' started by tjg358, Mar 29, 2013.

Scroll to continue with content
  1. tjg358

    tjg358

    4
    0
    Mar 29, 2013
    I am trying to regulate voltage on a snowmobile. system does not use a battery.
    voltage ranges from 0 ( at start up) to 20 vdc. max output is about 280w.
    I need to regulate a voltage to a digital temp gauge to no more than 13 vdc. Gauge has a 1 amp fuse ( per manufacturer )
    I see these very small 3 prong regulators but unsure how to install one or even if it is what I need. I an not an engineer but occasionally play with some of this stuff.
     
  2. duke37

    duke37

    5,364
    771
    Jan 9, 2011
    A 7812 regulator would do the job, it will do 1A.
    If the load takes 1A then the regulator will need to dissipate up to 8W so will need a heat sink.

    The main problem will be to protect the regulator from short term transients so I would suggest a 1A input fuse followed by a 20V zener to ground. If you measure the actual current consumed, then a resistor could be placed in series with the input fuse to drop the voltage at the regulator input so reducing the necessary size of the heat sink.

    The regulator will need capacitors at its input and output and a protection diode between input and output would be a good thing.
     
  3. tjg358

    tjg358

    4
    0
    Mar 29, 2013
    What if the system is protected with a 1amp fuse before the regulator?
     
  4. duke37

    duke37

    5,364
    771
    Jan 9, 2011
    If the input voltage goes above the zener voltage, then the zener may be asked to dump a lot of current so a fuze before the zener should protect it.

    The zener is there to protect the regulator.
    The regulator is there to protect the gauge.
     
  5. tjg358

    tjg358

    4
    0
    Mar 29, 2013
    I'm stupid here, can you possible hook me up with a parts list and a diagram?
     
  6. duke37

    duke37

    5,364
    771
    Jan 9, 2011
    Here is a sketch of the diagram. The zener should be over 1W.
     

    Attached Files:

  7. tjg358

    tjg358

    4
    0
    Mar 29, 2013
    Thanks. I'll give it a try
     
Ask a Question
Want to reply to this thread or ask your own question?
You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.
Electronics Point Logo
Continue to site
Quote of the day

-