[Vlad]

I admit I am electrically challenged

My electrical schematic is simpler then one of half century old Cub. No glass in the panel not much load. Wired per Vans drawings, new B&C 35A alternator and LR3 external regulator. Wired per their instructions all options trimmed.

The voltage drops when I switch alt. field ON, engine is running. There is a barely noticed beep in headset (SL40 on) and voltage slowly goes down till needle pegs. Vans voltmeter, only two wires out. What could cause that? Honestly I didn't dig deep enough in theory but checked all the wiring and ground. Email to B&C was not answered.

Momentarily I saw increase in voltage to 14V but no more.

 

[jdeas]

Mains voltage at zero?

Check the mains voltage across the battery. I would be surprised if it really is zero volts or the battery would be dead. If the mains really isn't at zero then check your gauges.

 

[AltonD]

Vlad, check the voltage to the field, pin 4 on the regulator. The fieled will pull quite a bit of current (5-6 amps). If you are seeing voltage, I would pull the alternator, take it to your local autozone-aviation store and have it tested.
What are you using for a current limiter on the alternator? I would check the voltage across this too. 14 volts and it is open.

 

[N15JB]

Vlad,

Get the trouble shooting page for your regulator, available on the B & C web site. It will walk you through a diagnostic tree for each pin, and tell you what the problem is if any pin is off spec. I just went through this for my LR3C.

Jim Berry
RV10

 

[PCHunt]

You might try taking the battery temp sensor out of the circuit, and see what happens.

 

[Vlad]

Vlad,

Get the trouble shooting page for your regulator, available on the B & C web site. It will walk you through a diagnostic tree for each pin, and tell you what the problem is if any pin is off spec. I just went through this for my LR3C.

Jim Berry
RV10

Jim I did that. All voltages and differences between them normal. The main suspect is the voltmeter. Will hook up the portable and check it in couple days. Everything is brand new - PC680 battery, B&C 40 amp alternator and external regulator. No heat sensor, no low voltage hook up.

 

[Vlad]

Defective voltmeter and B&C tech was right. Thanks Bill


Taped another foreign made device to iPad mount and taxied around with the rig . Everything works time to order a new voltmeter.

 

[turbo]

v, sounds like the fun is starting. what airport are you flying out of? will be nice to meet up some time soon.

 

[Vlad]

Ed I am out of Princeton/Rocky Hill 39N. Stop by any time if you are in the area. Cousin is trying to talk me into visiting you guys up north for breakfast some time.

 

[turbo]

v, i heard sky manor is the place to go in your area. will that 9 make it there?

 

[Vlad]

v, i heard sky manor is the place to go in your area. will that 9 make it there?

Niet, not yet in couple-three weeks. Sky Manor is fine place indeed the restaurant is on the field but the fuel price status was reported recently not as advertised.

Lucas Voltmeter was guilty today and punished by disassemblyage. Little smoke escaped but the needle was still dropping fast. Sledgehammer will be the next tool