Load meter never goes below 25% with nothing on, With landing lights, boost pump, Avionics master on appx 60% or Amps if you will. When cycling gear meter shows appx 70 or pegged, comes back down after gear pump shuts off. Just replaced master/alt switch. Bat checks good with load tester however gravity is low but above the bad/replace mark. Anyone had this problem before. Anyone with an Arrow notice what their load meter characteristics are.
If you indeed have no load, your load meter should read closer to 0 than 25% FSD. I assume by "no load" you mean everything that you can turn off is turned off.
You will still have battery charge current, and that's not insignificant right after startup. As well, you have alternator field current (2-3A).
I would suggest on your next flight, turn off all the electricals after about an hour of flying and check the load meter. By that time your battery charge current should be pretty low, and all you'll have as an electrical load will be the alternator field current.
If it's still high, then maybe your gauge is faulty. Or you have a battery problem brewing.
I am starting to suspect the battery. I took it out yesterday and charged it for approximately for 18 hours at 2 amps. The battery load test and the gravity test is good. I have not done a capacity test on it. Today when I put the battery in and started it up, with a fully charged battery the amp meter pegged when I turned the alternator on. It has never done that before. It seems that the battery is acting strangely. The airplane sits a lot in the hanger and was idle for about a month and a half and we cycled the gear quite a few times during the annual. Then we charged the battery with a slow 2 amp charge. The problem started after the annual. We also replaced the alternator with a plane power alternator. So I was automatically suspicious of the alternator change causing the problem. Thanks for your input,
John
It's also possible that your bus voltage may be on the high side, causing even a charged battery to draw charge current when the altenator is turned on. what are your battery voltage and bus voltage
measurements?
I keep a voltmeter plugged into the cigar ligher all the time so I can monitor both levels in real time. That way you can spot a problem brewing early.
Greetings--
I have recent experience with a similar problem on a '78 turbo Arrow III.
I monitor the load meter during gear retraction to confirm the power pack motor shut down at the end of the cycle. After an annual inspection in March, I noticed the load meter would indicate the pump running (about 50 amps with no lights or pitot heat) then in the last few seconds of the retraction cycle, would jump up to nearly full-scale deflection, then come back to less than 35 amps at the completion of the retraction cycle and pump motor shut-down.
On a recent night departure with all the lights and pitot heat on, I hit the gear switch "UP" and the load meter pegged off-scale and is presently stuck in that position.
A bit of corrosion was discovered on the ground strap attachment to the power pack motor. After that was cleaned up, the instrument cluster trim and faceplate was removed, and by golly, the ammeter needle was recovered from the full right deflection stuck position. It looks like the ammeter lives another day!
However, the gear actuation cycle is still suspicious. With beacon, strobes and avionics, the load meter shows about 20 amps. When the gear is retracted, the load meter jumps up to about 40 amps and as the retraction cycle progresses, the load moves up gradually to about about 60-65 amps until completion when the pump motor shuts down and the load meter returns to about 20 amps. Testing through airspeeds of 80 to 107 KIAS didn't show any differences so I don't think it is air-load related.
A full electrical load departure will probably peg the load meter, so we're looking further into power pack.
I'm assuming you are talking about the ammeter with the engine running. I'm not sure you have a problem. My Arrow meter shows about 25% with avionics on and about 60% during gear cylce. With landing lights(30) on and interior lights and running lights on the meter shows about 60% and almost full scale when gear is cycled.
You realize that even with "everything" off there is still power going to the electric flight instruments (turn coordinator, etc.) so the meter will never read 0.
