Please explain my meter to me.

Gallery, Projects and General > How do I??

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ieezitin:
Gentlemen.

I thank you all for your posts, Tinkerer the manual for the meter helps a lot thank you for the link.

Ok. Sorveltaja / Bernd I read both and let me see if I have this correct. I think I know what a diode is, I believe its function is to let current pass only one way a little bit like a check valve in a piping system, a resistor is a piece that when you lets say put 12 volt 2 amp current to one end out the other comes 9 volt 1 amp right? And the drop in voltage and amps is the resistance I think. So on the green scale of the meter the values are shown of what the particular resistor is resisting, and the one set on the scale that has the black arrow with a line through it and the music sign is the test of the diode ( open or closed).
Question here. In the diode tester position, is it true that if I had lets say had a cable with 3 wires in it and they are all the same color and I wanted to know what wire is what, and if I connect one probe to one end of one wire and try all the other ends with the other probe and it bleeps, the one that bleeps is the one wire that is connected to the other probe? And does this mean continuity, is this what that means?

The DCV / ACV I know, example if I put the two probes into the wall socket set the dial on 200 ACV the meter reads 125 that’s telling me that there is 125 volts ac which is what we use here in the US.

Now on the DCA / ACA I am really lost. You both say do not go to source current to find your amperage values well how do you do it.

HFE ok I give up.

Thank you all again. I am learning a lot. Anthony.

Bluechip:
Anthony

Why not just Google something like 'Using a Multimeter' ?

http://www.doctronics.co.uk/meter.htm#digital

This is the first one ( of many ) I got.

Before you destroy yourself/meter/circuit .... not joking ...

Seen it, done it, survived it. Some don't. 120VAC/240VAC bites. And bites hard. You need to know what you're doing, and why you are doing it.
Otherwise some thing will let go. Usually the meter, but not always ..

Dave BC

tinkerer:
You check continuity in the ohms position with no power applied. You can check continuity with power applied in the volts position, but there must be a voltage drop across the points you are testing.

Bernd:
Anthony,

Think of a diode as a one way valve. The hydraulic anlogy would be that the valve will only let the fluid, in this case electricity, flow one way but not the other. One use of a diode is to rectify AC to, what is known as half wave, DC. Four diodes wired together a certain way will give you a rectifier. This will give you full DC voltage. A full bridge rectifier is used in a circuit in a DC power supply. If I remember correctly a diode will drop .7 volt.

Yes, you can used the diode position to find the correct wire out of the three.

Individual components should all be check "out of circuit" if possible. Reason being there might be another path connected with the component that you want to check.

When using resistors in circuits you also need to consider the wattage of the resistor. Common wattges are 1/8W, 1/4w, 1/2W, 1W and so on up. I don't know how high they go.

Yes, the green scale will tell you the resistance. Try it out by checking a couple of resistors. I've uploaded a convenient resistor chart. Copy it and print it out.

When checking any value of voltage or current always set the meter to the highest setting if the voltage is unknow to you. Lets say you want to check the voltage of a transformer that is a step up transformer, in other words you put in 120volts and it doubles it to 240volts. Set the meter to at least the next higher setting. In your meter's case it would be 700volts since the 200 setting would not be high enough.

When checking amperage the meter actually needs to be put "into" the line. In other words you need to connect the meter with the current flowing through the meter. This is best learned by working with a 12 volt power supply.

Let me see if I can find a diagram or draw one up on how this is done.

Bernd

75Plus:
Continuing Bernd's hydraulic analogy. a resistor is similar to a restrictor plate or orifice and a capacitor works like an accumulator.

One more item that should be addressed is amps supplied to a circuit. No matter what the power supply can supply in amps the load will draw only the current, (amperage), to operate the circuit. In the case of a motor, with no load applied, the current drawn will be low. As the load increases the current will increase also. If you have a fixed load, such as a 12 volt, 12 watt, light bulb the current flow will be 1 amp with 12 volts applied. There is no way to send more current into the bulb if the voltage remains constant.

Joe

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