Dual Batteries-No Power on #1

[AZOutlaw]

I have dual batteries in an Ovation.  Each battery has a relay mounted near it. Went to fire up today and all was dead, switched to battery #2 and all was normal.  I'm going to assume that the #1/#2 battery selector on the panel energizes (closes) the called relay selecting that battery.  Has anyone had one of those relays go out?

While running, #2 shows a normal amp charge rate.  Switching to #1, the amp rate goes to zero like nothing is connected.

[Fritz1]

Sounds like dead #1 battery relay, select #1, turn master on and see if any power comes out of #1 relay, which is connected to left battery, power comes in on large terminal that is connected to battery and goes out from other large terminal, connect test light or voltmeter to large terminal that is not connected to battery and ground, if no power coming out and all terminals on relay and battery are tight and small terminal on relay is getting power, battery relay is most likely dead, they are made by a company with the name of Kissling, Lasar probably has them in stock, I replaced one of mine in my 2000 Bravo about 2 years ago, think it was about $350 then

[Jeff Uphoff]

2 hours ago, AZOutlaw said:

I have dual batteries in an Ovation.  Each battery has a relay mounted near it. Went to fire up today and all was dead, switched to battery #2 and all was normal.  I'm going to assume that the #1/#2 battery selector on the panel energizes (closes) the called relay selecting that battery.  Has anyone had one of those relays go out?

While running, #2 shows a normal amp charge rate.  Switching to #1, the amp rate goes to zero like nothing is connected.

As I recall, some items, such as the cigarette-lighter adapter and the baggage-area light, bypass the master and are tapped directly off the #1 battery through fuses. So if you can still turn your baggage light on, that would seem to indicate battery #1 is good and the relay is bad.

(If I'm wrong about this, I'd love to be corrected! But I killed my Ovation's #1 battery earlier this year when I didn't notice the light had been bumped on and then the timer failed...so the light stayed on; the master was of course turned off.)

[GeeBee]

I have had #2 relay go dead on me. Replaced it, all was good again. Usually it is the little diode on the coil that goes bad as the rest of the unit is pretty robust.

[M20F]

I would also check cables for corrosion.  Hit them with wire brush dremmel and then dylectic grease.  

[AZOutlaw]

I finally made it back to the hangar with my voltmeter.  The #1 battery was totally dead, like 0v dead, while in the plane.  (#2 was at 25v)  I took it out of the plane and it slowly started to come back to life.  It had about 6v in it when I left.  It will go on a charger.  The NO relay was also closed all the time with no power.  It also had 2 blown 5a fuses connected to it.  I'm fairly certain it's a bad relay.  My mechanic and I decided what to order and now we wait a few days until it comes in.  I'll post a final update later.  Thanks for all the help and happy flying!