How do I measure resistance using a multimeter?

Question

I have made a battery pack for my maglite using some aa batteries, and some springs and wires. I need to know how to mesure the "resistance" uning a digital multimeter, ie where to connect the leads to, what setting to turn the dial to, I just dont want to blow my fuse, and the instructions on this are unclear. Thanks in advance.

Answer 1

You turn the multimeter to resistance setting, and it puts out a voltage/current on the test leads.  However, since it has it's own current source, you can't (for example) measure the resistance of your battery pack.  You can only measure the resistance of non-powered items, like the light bulb.

Answer 2

Turn it to the one with the Ohm sign.  It looks like an upside down horse shoe.  As long as you don't run a current through it you shouldn't blow any fuses.

Answer 3

There are two things you need to check every time you use a multimeter.

1. The set up (leads plugged into correct place)

Some multimeter's come with detachable leads. You will want to make sure that one leads is connected to the meter at the "+/red" and the other is connected to the "-/com/black' terminal.

2. Integrity of the meter leads (ohm check)

Turn the meter dial to the setting marked with the Ohm symbol (upside down horse shoe). The meter will display "OL" for overload or open line. Then touch the two meter leads together. The display should show close to 1. The actual number you get is the resistance of the meter leads and meter itself. So if you get 5ohms during this self test, you should subtract 5ohms from any further readings you take.

You can test the resistance of your battery pack minus the actual batteries. As the posters before have said, you can not test a 'live' circuit for resistance. That means there must not be any power (batteries) during your testing. Without a power source, you will not blow the fuse in your meter.

To test the resistance of the battery pack itself you can place one lead where the "+" end of your battery would normally contact the battery pack circuit. The other would be placed where the "-" end connects.

Hope this helps.