fbpx

 

How hot should the Rotax rectifier/voltage regulator get?

I have mounted mine on the cockpit side of the firewall, in the hope that it would run cooler away from under cowl heat but it still seems to get very hot (cant keep my hand on it) to the touch.

  • Re: Rectifier Temperature

    by » one year ago


    170F+ is a killer. A few things affect the temp. Location (air flow), too little draw or too much draw. Place it in a place that gets good air flow whether it's in the engine compartment or inside. If it's inside place a computer fan on it or another fan to move some cooling air over it. I used to place temp strips on my ignition modules and VR. Both mine had good air flow and the temps were  approximately 140F.


    Roger Lee
    LSRM-A & Rotax Instructor & Rotax IRC
    Tucson, AZ Ryan Airfield (KRYN)
    520-349-7056 Cell


    Thank you said by: Sean Griffin

  • Re: Rectifier Temperature

    by » one year ago


    If you can direct incoming air from the mouth of the cowl or from a NACA duct directly onto the regulator via a blast tube, it will be happier than behind the firewall with no airflow.  Outside air directed via a blast tube lowers the localized ambient temperature seen by the regulator, so it runs significantly cooler than it would if hot under-cowl air were moving across it from natural air currents.


  • Re: Rectifier Temperature

    by » one year ago


    Roger Lee wrote:

    170F+ is a killer. A few things affect the temp. Location (air flow), too little draw or too much draw. Place it in a place that gets good air flow whether it's in the engine compartment or inside. If it's inside place a computer fan on it or another fan to move some cooling air over it. I used to place temp strips on my ignition modules and VR. Both mine had good air flow and the temps were  approximately 140F.

    Hi Roger,

    Please expand "........, too little draw or too much draw........."

    Too much makes sense but what of too little??

    AND

    What would be the Goldilocks voltage range??


  • Re: Rectifier Temperature

    by » one year ago


    Mine is mounted inside the firewall, near a fresh air NACA duct 2" scat tubing. I cut a small 1/4" hole in the scat tubing pointed at the rectifier to blow some outside air over it continuously. Been working good for about 6 years.


  • Re: Rectifier Temperature

    by » one year ago


     "........, too little draw or too much draw........."

    It is a shunt regulator.
    Too much Draw ... Excess current  (>30A) will cause Overheating.
    Too Little Draw ... Minimal Draw (<<5A) causes the regulator to shunt the excess power to ground, causing Heating.

    The Voltage will be 14.0 to 14.2 measured on the Battery.
    The Voltage measured on the Bus may be slightly lower.


    Bill Hertzel
    Rotax 912is
    North Ridgeville, OH, USA
    Clicking the "Thank You" is Always Appreciated by Everyone.


    Thank you said by: Sean Griffin

You do not have permissions to reply to this topic.