regulator output

[C170U2]

How does one verify that the voltage regulator is putting out the correct amount of voltage? I believe it should be around 14.3 volts. All I have is an ammeter in the panel. Where would I connect my handheld voltmeter to verify output? I think I might be overcharging the battery. Thanks!

[blueldr]

I would think that the voltage could be checked anywhere on the buss when the engine is running.

[Bruce Fenstermacher]

The first one Arash showed is (was) available at WalMart. I modified one to have a power plug extending from it and the unit then lives in my cigarette plug. I then plug into the added plug for all the other temporary gizmos in the cockpit.

[C170U2]

Thanks guys. That looks a lot safer than me trying to jerry rig the voltmeter in flight. It will be good to know what is going on voltage wise.

[GAHorn]

Sporty's Pilot Shop offered a similar unit was useless... as it would not read anything above 14 volts exactly.
My '53 model instrument panel had an unused 2.25" instrument hole in which I installed a volt-meter. (Volts are so much more useful than an ammeter.)

[Bruce Fenstermacher]

If the unit didn't go over 14v it would be useless. The first unit pictured from Innova does. My regulator is adjusted a tad high. OK most times but I have seen over 15v on it which is when I start turning on stuff to drop the voltage. Partner Leroy just shrugs and doesn't much care. Mumbles something about measuring with a micrometer when your cutting with a torch.

And yes volts tell you more than amps most times in our airplane.

[GAHorn]

All good and correct words, Bruce.
If one checks resources one will find that up to 15.5 volts is acceptable performance (but, while that will not hurt your appliances/radios... constantly up that high will reduce the lifetime of your ships battery as it evaporates electrolyte and "cooks" plates.)

Ideal charging voltage will hover around 13.7 volts, according to most sources.

Another thing... a meter which will not display below 11 volts is also of not much use.... Select one which will operate between 10 and 16... or a wider range. With master ON...engine not running....Anything less than 10 while cranking indicates a weakened battery. With charging current applied, anything more than 16 indicates a charging system in trouble.

[DaveF]

Ideal charging voltage will hover around 13.7 volts, according to most sources.

Teledyne (Gill) and Concorde call for a bit more than that.

BatteryChargeVoltagesGill.JPG

BatteryChargeVoltagesConcorde.JPG

[Bruce Fenstermacher]

I tested the Innova dcv meter pictured. It will light and show 6.75 volts reliably. You might see as low as 6.73 volts then the digits go blank. On the high end it will show 18.75 volts. At some point between that and 26 volts it goes into an overload condition and just shows a 1. I think this is probably at 19.99 volts because the circuit is probably not set up to drive a 2 in the first digit. I have two of these. As I said on lives in the cigar lighter in my 170. The other is highly modified with plugs in and out and I use it in conjunction with a small solar panel to designed to keep cars batteries at peek while being shipped from Europe. The setup is used to charge the 5 amp battery I use in my Cub for intercom and handheld radio.

[GAHorn]

The term\ I used.."ideal" .... was not well defined by me, I admit.
What was meant: 13.7 will meet the charging requirements of systems without hazard of either overcharging a battery or undercharging it.
The temperature of the battery depicted in those charts are of interest. One ordinarily does not know their battery temperature...but consider the fact that it is sitting in a compartment with an engine running CHTs of 300+ and exhaust systems of 1200+ and you will see that battery temps easily run in the high end of those charts. I stand by the 13.7 recommendation as an "ideal" to shoot for.