Measuring resistance with a multimeter

To measure the resistance of a component it must not be connected in a circuit. If you try to measure resistance of components in a circuit you will obtain false readings (even if the supply is disconnected) and you may damage the multimeter.
The techniques used for each type of meter are very different so they are treated separately:

Measuring resistance with a DIGITAL multimeter

1. Set the meter to a resistance range greater than you expect the resistance to be.
   Notice that the meter display shows "off the scale" (usually blank except for a 1 on the left). Don't worry, this is not a fault, it is correct - the resistance of air is very high!
2. Touch the meter probes together and check that the meter reads zero.
   If it doesn't read zero, turn the switch to 'Set Zero' if your meter has this and try again.
3. Put the probes across the component.
   Avoid touching more than one contact at a time or your resistance will upset the reading!

Measuring resistance with an ANALOGUE multimeter

The resistance scale on an analogue meter is normally at the top, it is an unusual scale because it reads backwards and is not linear (evenly spaced). This is unfortunate, but it is due to the way the meter works.

1. Set the meter to a suitable resistance range.
   Choose a range so that the resistance you expect will be near the middle of the scale. For example: with the scale shown below and an expected resistance of about 50k choose the × 1k range.
2. Hold the meter probes together and adjust the control on the front of the meter which is usually labelled "0 ADJ" until the pointer reads zero (on the RIGHT remember!).
   If you can't adjust it to read zero, the battery inside the meter needs replacing.
3. Put the probes across the component.
   Avoid touching more than one contact at a time or your resistance will upset the reading!

Reading analogue resistance scales

For resistance use the upper scale, noting that it reads backwards and is not linear (evenly spaced). Check the setting of the range switch so that you know by how much to multiply the reading.
Sample readings on the scales shown:
× 10 range: 260
× 1k range: 26k
If you are not familiar with reading analogue scales generally you may wish to see the analogue display section on the general meters page.