Ammeter fluctuating

[zerotact]

Something Similar to this? Maybe a little more prominent.

IMG_1149.MOV

[tony]

Looks like your running a little hot.  That oil temperature and pressure doesn't make you a little nervous? 

[mooniac15u]

Something Similar to this? Maybe a little more prominent.

IMG_1149.MOV

That looks like it might be at least partially a grounding issue. With the M20J a bad ground will cause the two temperature gauges to read high and the rest (oil press, fuel press, fuel quantity) to read low.  Since it seems to be affecting multiple gauges it could be the main airframe ground.

[buddy]

I had the same problem on my 201, on the back of the key switch mooney uses spade connecters, you have to go under the panel with a screwdriver and push all the spade connecters back on tight on the back of the switch.  This will not be a permanent fix you will have to do this every time you see your ammeter start jumping around and I had my 201 for about 30 yrs. so you can plan on doing this once a year.  This was not one of mooneys better ideas.

[mike_elliott]

Peter, did you ever get this fixed? If so, what was the fix?

[MARZ]

I am also having the same problem of the amps fluctuating. I checked the terminals on the Master switch and they are clean, absolutely no corrosion. The volts stay steady, which makes me think it is not the voltage regulator. The amp fluctuation goes away if I take the alternator off line. Popping every CB with the alternator on does not result in the fluctuations disappearing. Interestingly though, when I pop the announciator panel CB, it automatically takes the alternator off-line, and I have to reset the alternator CB in order to get it back on.

The alternator and the battery are about 1 year old. What do you guys think...it seems that there is an alternator connection to all this - diodes?  I have the PlanePower Alternator installed. Also, why does popping the Announciator panel CB result in the alternator going off-line?

Thanks

Stefan

With the Alt off the dips are evenly spaced - like maybe a strobe power supply?

[romair]

Strobes were off...

Also, with the alternator off there is a significant difference in the fluctuation (almost none) then with the alternator on.

i recently checked the alternator with a car tester and while I was expecting it to say that there is a problem with the charging system, it actually gave it an "an okay"

stumped by it...

[PTK]

Peter, did you ever get this fixed? If so, what was the fix?

No Mike, I haven't had the opportunity to tackle it. I can say with certainty that the fluctuation is RPM  dependent. 

[MARZ]

Hmm - it really seems to me that the Amps are reacting to some type of draw, your volts are remaining pretty level.   Have you pulled all the breakers and monitor the amps?  if it levels out, engage one at a time and watch the fluctuations.

[PTK]

I'm happy to report the ammeter fluctuation is no more! Condition cured!

Battery is good and so is alternator and master connections. What I did was remove the left most panel piece that the ammeter is on along with clock and ignition switch. My goal was to check the connections to the ammeter, clean them and tighten them. There are two boots that cover and protect the connections behind the ammeter. One had slid off exposing the connector so I secured it. The other was in place. That seems to have solved the fluctuation.

[mike_elliott]

On ‎1‎/‎8‎/‎2016 at 7:17 PM, PTK said:

I'm happy to report the ammeter fluctuation is no more! Condition cured!

Battery is good and so is alternator and master connections. What I did was remove the left most panel piece that the ammeter is on along with clock and ignition switch. My goal was to check the connections to the ammeter, clean them and tighten them. There are two boots that cover and protect the connections behind the ammeter. One had slid off exposing the connector so I secured it. The other was in place. That seems to have solved the fluctuation.

Was it just  that one of the boots slid off, or did you clean and tighten the connector and did you clean the master switch terminals? I am  Glad  the issue was resolved, Peter.  I wonder how in the world a dust boot could slide off in the first place, but I bet so do you.

[Cardinal767]

Glad I'm not the only one who had this issue. I kept it simple and followed the advise listed above. EDM 800 showed the voltage jumping up and down 13.5 to 13.8. For me it was the ground wire on the back of the alternator. Fixed with a couple of turns of the screw. Thanks for the help gentlemen.

Bob G.

[carusoam]

The power of MS...

Best regards,

-a-

[jerrybeach]

Amps fluctuating regularly every two seconds from small charge to large discharge. Volts stay between 12.3 and 13.5 under heavy load. Have a new battery and voltage regulator. I can hear it in my head sets. It acts like a very high amp strobe cycling, but l have shut the strobe off. Thanks, Jerry 

[carusoam]

Welcome aboard Jerry!

Got a question to go with that, or just your observation?

Best regards,

-a-

[PT20J]

On 6/15/2021 at 7:38 PM, jerrybeach said:

Amps fluctuating regularly every two seconds from small charge to large discharge. Volts stay between 12.3 and 13.5 under heavy load. Have a new battery and voltage regulator. I can hear it in my head sets. It acts like a very high amp strobe cycling, but l have shut the strobe off. Thanks, Jerry 

Try pulling the circuit breakers one at a time to isolate the circuit. If this started after replacing the voltage regulator, check that.