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Everyday that your airplane sits on the ground, your batteries are being slowly destroyed by sulfation caused by the aircraft's parasitic current drain.  In just 16 days, it can erase 10% of your battery's capacity. 


Here's the facts:

  • Your Battery Bus Contactor constantly draws a small amount of electrical current from your System Battery.  That current drain causes sulfation of the battery's negative plates.  That increases the battery's internal resistance, effectively reducing your battery's capacity.

  • At each 6 month battery capacity check, when the batteries are swapped side to side, the opposite battery is subject to the damaging effects of the parasitic drain.

  • The longer your battery remains in a state of partial discharge, the less likely you are to be able to reverse the capacity loss caused by parasitic drain.

  • In our testing (see Blog pages) the use of a Battery Minder product produced NO measurable improvement after 21 days of Battery Minder use.

  • If supply voltage is lost to a Battery Minder, the additional parasitic drain caused by the Battery Minder can greatly accelerate the sulfation of your batteries.

For about the cost of your next set of replacement batteries, you can modify your Battery Bus Contractor to reduce the parasitic drain to 1/1000 of the current rate.

As an added bonus, all Battery Bus Contactor upgrades after May 1, 2018 come with STC SA04306CH at no additional charge.  This STC allows you to extend the battery capacity check interval to 12 months when the aircraft is equipped with RAS repaired or new PMA batteries.

To upgrade your Battery Bus Contractor, purchase the upgrade from our on-line store.  When your purchase is complete, you will receive an email with shipping instructions.  Have your local mechanic remove your System Battery Bus Contactor and send it to us.  We will modify your unit and send it back to you.  Turn around time is normally 1-2 days.  

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