ovation backup alternator question

[Tommooney]

HI:

I was re reading my POH and noticed the procedure for stdby ALT #2 below says: " pull Battery CB '. The run up procedure to test does not. I have done the runup test procedure many times but never needed an actual backup in emergency so never pulled this CB.

The Battery CB does not seem to pull out like the smaller ones easily do. ( the other two adjacent 40A CBs also do not pull easily ). See photo. They only push in but come right back out with no click or snap.

I am wondering what I am missing to "pull the battery CB " before I pull really hard and screw it up. Its probably really simple. I probably am not understanding how this CB works?

Everything seems to be working fine unless this is a problem.

Thanks for any help.

[GeeBee]

You are isolating the battery to save it for gear and flap extension. The SBY alternator is self exciting, but it cannot generate the amperage to power the emergency bus equipment and charge the battery with the equipment attached. By pulling the breaker, you are isolating the emergency bus to the alternator and saving the battery for gear and flaps.

[Tommooney]

That part is what I thought about saving the battery.

Its the 70A CB that doesn't " pull " out like the smaller ones. It pushes in but doesn't click. I'm worried that if I pull harder, I will break it. In the photo, you can see it is different than the smaller CBs to left. it is similar to 40A CBs to its right. So the question I'm having is how to " pull " the 70A CB.

[StevenL757]

2 hours ago, Tommooney said:

That part is what I thought about saving the battery.

Its the 70A CB that doesn't " pull " out like the smaller ones. It pushes in but doesn't click. I'm worried that if I pull harder, I will break it. In the photo, you can see it is different than the smaller CBs to left. it is similar to 40A CBs to its right. So the question I'm having is how to " pull " the 70A CB.

To add to @GeeBee's correct remarks above, and to answer your question, that 70A breaker is a thermal device with a "latch" of sorts; that when pressed, it locks things over-center to close the breaker.  It is a different model than the Klixon breakers elsewhere in your panel, and is this way by design.  The answer to your question is Yes - it does indeed require roughly 2x to 3x the force to pull it open as the rest of your breakers, and you're right to ask the question.

[GeeBee]

Put a collar on the breakers and it will pull (and push) easier. I color code all my breakers so I can easily locate them during a non-normal procedure (I put the color on the checklist too)

 

I like the KrisMark ones the best

 

https://skygeek.com/dance-air-10164-5-circuit-breaker-collar-red.html

[Tommooney]

Thank You GeeBee and Steven757: 70A CB did " pull " off at about 3X more force than smaller breakers the first time. Subsequent pulls were 2X harder. I guess I should exercise them all once a year. Never have before.

All good now. Nothing broken.

Tom

[carusoam]

Great question….

and fantastic follow-up!

 

The bigger the CB… probably the bigger the pull….

They all need to trip, reset, and indicate when they have tripped…

+1 color coded CBs….

You have to be really young, or have tremendous memory, and be really cool under fire…. To be able to find the ones you want in an emergency…

 

Best regards,

-a-

[Tommooney]

Your right! I just ordered the color CBs.  One time the stall vane came physically disconnected and went off at 10K' over OR coast. Took seemingly forever to figure out what loud horn blaring was and how to turn it off ( not expecting stall horn at 180 knots ) by pulling CB. 

But what is  " STBY BUS BAT "  CB in photo above: 6th row down, 4th from left. 

Thanks

[carusoam]

1) Main Bus

2) Avionics Bus

3) Emergency Bus

4) Stand By Bus

5) Stand BY Bus Bat

 

I was good up to line 3….

-a-