SK Battery Backup and navigating w/autopilot

[marc17522]

Do I understand that you do not have the glideslope coupled to the autopilot yet? When I put a flight plan in the 430W it is not displayed on the SV screen! I have two 10" skyviews. 1 with a battery backup, when the voltage reached 10.4 both screens flickered on and off, then at 10.3 volts the screen with out the battery back up turned off then tried to boot back up. The SV with the battery back up never did stabilize out, just fickered on and off, Is this working properly?

Marc

 

[dynonsupport]

Do I understand that you do not have the glideslope coupled to the autopilot yet? When I put a flight plan in the 430W it is not displayed on the SV screen! I have two 10" skyviews. 1 with a battery backup, when the voltage reached 10.4 both screens flickered on and off, then at 10.3 volts the screen with out the battery back up turned off then tried to boot back up. The SV with the battery back up never did stabilize out, just fickered on and off, Is this working properly?

Marc

SkyView AP does not yet support glideslope.

While Flight Plans in the 430W will not display ON SkyView, if properly interfaced (via SkyView SV-ARINC-429), and the 430W is selected as a NAV or GPS source, SkyView AP will execute a Flight Plan from the 430W.

SkyView components are spec'd to operate from 10-30 volts; sounds like you're at the margins with your system, but if your voltage reading is accurate, SkyView should be operating properly. But, what might be happening is that the supply voltage is (barely) above 10V, but when equipment is turned on, the load through the wire drops down the voltage so that the voltage at the wire is much closer to SkyView's threshold voltage.

Regardless, if the battery is charged, a SkyView system should operate fine on marginal voltage.

SkyView actually requires a voltage above 12.25V to simultaneously operate and charge the battery.

 

[marc17522]

So when the main battery runs down the back up does not take over, it will just flicker? The back up battery ran the SV once I turned off the main power!!!

Marc

 

[dynonsupport]

So we've replicated what you're seeing.

There's nothing "bad" going on here, but essentially, you're getting SkyView right up to the threshold voltage where it switches between external and backup battery power. It looks like when you're right near that switchover point (10ish volts) via regulated power, SkyView can end up trying to rapidly switch between the backup battery and external power. You see this as a flickering on the display, as the internal power supply adjusts between battery and external power. SkyView shouldn't do this ideally, but it's not a cause for alarm, nor does it compromise SkyView's backup battery capability.

In a real emergency, an aircraft battery at that voltage would pass through that voltage quickly, and so this shouldn't pose a threat to SkyView operating on the backup battery.

This behavior also shouldn't damage the unit.

We're going to look into tuning the power management software to eliminate this phenomenon in the future.

However, we suggest that if you're using an external power supply to , to use one that can provide power higher higher than 10V (let's call it 12V+, just to pick a number that's well-clear of the threshold) with sufficient current to power the display (about 3.5A at 12V - this changes with voltage, obviously).

 

[dabear]

I put a suggestion in the suggestion section for a readout on how much time left on backup battery there is left for the SV and notification as to when on backup battery.

I had a charging problem today on my flight and was up on backkup power for a time. BTW, this caused flicker on screen 1, but not on screen 2. (screen 3 was turned off by breaker as there was no one in the back)

BTW, it took about 20 min with everything shed except SV (-5 amps) to go from 24 volts to 23.5 volts. I didn't get to 10ish volts.