TCW Backup Battery

[mmarien]

Is anyone using the TCW backup battery (IBBS-12v-4ah)?

I was wondering if I can just connect the TCW Master Switch to my Master switch so the backup battery comes on with the Master. What benefit is there to have a separate switch to turn on the backup battery? The operation seems automatic as long as the TCW master switch is on.

 

[dynonsupport]

Why would you prefer the TCW to the Dynon battery for a SkyView? Or are you powering something else with it?

 

[mmarien]

We're powering something else (not Dynon - sorry, not my decision) .

The aircraft is a VFR GlaStar. We're trying to make it simple and basic without omitting important items. The backup battery powers the display and engine instruments if the alternator quits and the main battery runs down or during engine starts. I'm trying to think of a situation when I need the separate switch for the backup power. Would I ever need to shut off the master but still want power to the display?

The only reason I can think of for backup power in a VFR aircraft would be maintaining power to the display during engine starts but I'm open to discussion.