Using a digital multimeter to test for a connection?

[Lord Ned]

Title may be a little off, but I've got a three pronged power input, (It's not your standared CPU, it's for Servo's) and I think it only requires two of the prongs. So is there any way of using a Multimeter such as this one:

to test if two of the pins make a complete circuit?

Thanks. And the specs on the multimeter:

Measure DC voltage in these ranges: 200 mV 2000mV, 20V, 200V and 1000V.
Measure DC current in these ranges: 200µA, 2000µA, 20ma, 200ma and 10A.
Measure AC voltage in these ranges: 200 V and 750 V.
Measure resistance in these ranges: 200, 2000 ohms, 20, 200 and 2000 Kohms.

[silverdemon]

You could meassure the resistance in the circuitry, close to 0 ohms resistance is a connected circuit, real high values (or --) means it's'not connected..

but wouldn't it be simpler just to try with two wires connected? If that works you'ré set... The third wire might be needed to activate something (like the green wire on a 20-pin or 24-pin motherboard connector)

hope that helps

[Lord Ned]

I would but I don't even know the voltage required for it... This thing is 17+ years old.

[xmastree]

Are we talking about the mains connection? Is it any different from the usual PC connector?
The centre pin is usually the earth and while not essential, it's a good idea to use it.

A picture would be really useful here.

[Lord Ned]

http://hailaeros.com/miscfiles/car.jpg

Third for fourth, it's the closeup picture that says BATT.

Very large image, sorry.

[xmastree]

http://hailaeros.com/miscfiles/car.jpg

404


and what does 'third for fourth' mean?

[Lord Ned]

Whoops, Third OR forth, and I forgot to capitalize the C. Odd.
http://hailaeros.com/miscfiles/Car.jpg

[rendermandan]

If its 17 years old, I"m not sure what technology they used back then, but if it is the same as now, the three wires are as follows.
Red: Positive 4-6V power
Black: Ground
Yellow/Other color: PWM Signal (Pulse width Modulation)

The PWM signal is what tells the servo where to go and stay there.

I'm not sure what you are using this for, can you describe what your purpose is a little more? then I might be able to help a little more.

later!

[xmastree]

I was thinking about computers, but then I misread Servo as Server...

The two outputs are probably as renderman said, but I don't know why there would be three terminals on the battery connector.

[Lord Ned]

But why would it be PWM on a battery? It doesn't control the servo's... The servos all have the PWM though so... Hmmn.