[John Orr]

John Orr on October 12, 2018 at 3:28 am #18799

I believe the shunt may be internal to the ammeter gauge in which case installing an external shunt with the regular gauge would show the symptoms that you have.

[John Orr]

John Orr on October 12, 2018 at 3:26 am #18798

Exactly! And that diode went bad. A rather expensive part to replace.

[CHARLIE MUELLER]

CHARLIE MUELLER on October 11, 2018 at 3:26 pm #18797

Thank you, my mechanic said that there was no shunt either. He installed a shunt and a 60amp breaker as well as a new ammeter gauge and I still cannot get any load on the ammeter-needle all the way to the left even with everything on. Alternator tests ok, battery ok. He also adjusted voltage regulator.

[STEVE]

STEVE on October 11, 2018 at 2:03 pm #18796

Hi Stan; Thank you very much. I never knew that. Very good to get that piece of information in the data base.
Best regards,

Steve

[Stan Holm]

Stan Holm on October 11, 2018 at 8:42 am #18794

I happen to remember the early taper wing single engine Pipers used a large diode on a heat sink instead of a 60A circuit breaker. It is installed between the ammeter and the master relay on the 6 gauge wire. I just verified that by looking at an early Arrow wiring diagram – I don’t have a Warrior manual.

[John Orr]

John Orr on September 20, 2018 at 9:54 am #18772

I would be happy for someone to prove me wrong, but the wiring diagram for my PA28-151 clearly shows that there is no main breaker for the alternator output. It is strange. The wiring diagram is on page 2H24 of the PA28 151/161 maintenance manual.
John

[STEVE]

STEVE on September 20, 2018 at 7:06 am #18768

Hi Charlie;
What a puzzle. Why would anyone replace the alt CB? Glad you did what needed to be done.

[CHARLIE MUELLER]

CHARLIE MUELLER on September 18, 2018 at 4:40 pm #18767

John, I recently purchased a 1981 Piper Dakota and it has an alternator field circuit breaker on the breaker panel but there is no 60 AMP Alternator breaker anywhere. The wiring diagram, clearly
shows one so we assumed it was removed by a previous owner. I had a 60 AMP breaker installed.

Charlie

[John Orr]

John Orr on August 15, 2018 at 12:54 pm #18730

Hi Steve,
Thanks for the reply. I agree with you but Piper has hidden the breaker very well if it exists on my PA28-151. And I have studied the wiring diagram from the maintenance manual. No breaker is shown. I would paste the diagram here if I could. It’s on page 2H24 of the PA28 151/161 manual.
John

[STEVE]

STEVE on August 15, 2018 at 11:31 am #18728

Hi, I’m sorry it’s taken a while to answer this. I distinctly remember typing out an answer to this question.
There’s no way Piper sent your out the door without an alternator circuit breaker. All electrical circuits, especially ones capable of handling 60 amps, are required by regulation to have circuit protection.
In all the manuals I have for the PA 28 series airplanes, there’s a 60 amp circuit breaker. I suggest you look at the circuit breaker panel; one of my Owner’s Manuals shows the alternator circuit breaker adjacent to the alternator field circuit breaker in the main breaker panel.