2-pin polarity puzzler...

[helifella]

Hey all,

Trying to determine the correct polarity of the round, two pin, female connector in the passenger footwell of the JR my company owns. I'll be blowed if I can find a wiring schematic anywhere. Of the two pins (labelled A and B), which is supposed to be the positive pin and which is the negative pin? I have determined on this JR that it is a 24V dc output with B being the positive pin. Don't know if this is wired correctly or not. Any help much appreciated, Google has let me down...

[bb in ca]

Hey hf,

You might be searching for a very long time. I've never seen a schematic for these set-ups.

I know when I used to work on and fly 206's, in Canada, the saying that I was taught by someone who had been around them longer then I was simply, "Be positive". I always checked the polarity in a new aircraft if I was plugging in something I knew was sensitive to reverse polarity.

ttf

[effortless]

Get yerself a meter mate.

[Bertie Thruster]

meter mate

The lovely Rita is even better! The right polarity and a smile.

[spinwing]

As well you might consider Diode protecting any electronic items that you wish to plug in to the aircraft ... this is easily done and will eliminate the worry of a reverse polarity connection.

Cheers

[GoodGrief]

You guys can't be serious.
Get meter, adjust to 200V DC.

plug in cords, usually red and black.
If value is positive then red pin is positive, black is ground.

If display shows negative ("-") then black pin is positive.

[effortless]

Der I finked that was what I wus sayin'.

[GoodGrief]

I fought fo

[farsouth]

Think the suggestions about getting a meter are missing the point and not answering the question asked.

Helifella has already determined that it is 24vDC and that pin B is positive on HIS aircraft, but is asking if that is how it is supposed to be wired..........

[GoodGrief]

right you are, forget everything I wrote.Apologies.

[forget]

You guys can't be serious. Get meter, adjust to 200V DC. plug in cords, usually red and black. If value is positive then red pin is positive, black is ground. If display shows negative ("-") then black pin is positive.

Then again, meters are expensive and the nearest may be hundreds of miles away. Bush fix. Strip some wire, mains stuff will do, so you have only one single strand. Turn the power on, stick the strand in one of the plug connectors and connect it to earth. It it ignores this event, that's earth. If your hand gets warm and the wire disappears, that's +.

Worked for me.

[chuckolamofola]

Normally "B" is positive and "A" is negative. I've seen some people swap them due to other equipment needs, but the standard configuration is "B" is positive.

What are you connecting to it?

Regards,

chuck

[GoodGrief]

Finally found it, I guess.

Maintenance Manual, wiring diagrams chapter 98, 98-00-00, page 6, aux power circuit, figure 98-3 (it's a Long Ranger 3, but should be the same).

chuckolamofola is right, B is 28V.

GG