I using my digital multimeter

[richyw]

Hi, this might seem like a really stupid question, but I am not sure how the scale works on my digital multimeter. I am trying to measure the resistance across a photocell in the light and in the dark.

I was given this digital multimeter as a gift, but am unsure how to use it. The instructions do not really help. What I did was switch the dial to where there was an omega symbol, assuming that would be the place to be for resistance!

So there are 5 different settings, 200, 2000, 20k, 200k and 2000k. I am guessing that these will select my "range" much like other meters I have used in the lab. So now I have found one measurement. It displays 5.84 on the "200k" setting.

So what the heck resistance does that work out to?

I've watched like 3 youtube videos and I think they all skip over this because it is so trivial!

 

[vk6kro]

If your meter has ranges of 200, 2000, 20k, 200k and 2000k, this means the maximum resistance it can measure on those ranges is 199.9 ohms, 1999 ohms, 19990 ohms (19.99 K), 199900 (199.9 K) and 1999000 ohms(1999 K), assuming this is a 4 digit meter with the first figure no more than 1.

So, you couldn't get a reading of 5.84 on the 200 K scale because that can only give one decimal place (up to 199.9 K ohms).

However, you could get that reading on the 20 K scale. It would mean that your resistor was 5840 ohms approximately. That is 5.84 K.

 

[richyw]

sorry I am still very confused. why can I not get 5.84 on the 200k scale? I'm pretty sure I got that.

 

[vk6kro]

sorry I am still very confused. why can I not get 5.84 on the 200k scale? I'm pretty sure I got that.

Assuming you have a 4 digit meter, you will see that the decimal point on that scale is one digit in from the right hand side.
So, you could get a reading of 5.8 or 5.9 but not 5.84.

 

[alphysicist]

Hello there,

First of all, there are no stupid questions when it comes to learning and using new equipment. It's great that you are taking the time to figure out how to use your digital multimeter.

To measure resistance with your digital multimeter, you need to set the dial to the omega symbol, which represents the unit for resistance, ohms. The different settings, such as 200, 2000, 20k, 200k, and 2000k, represent different ranges of resistance that your multimeter can measure. The higher the number, the higher the range. In your case, you have selected the 200k setting, which means your multimeter can measure resistance up to 200,000 ohms.

Now, the reading you got, 5.84, is in the unit of ohms. This means that the resistance across your photocell is 5.84 ohms. This may seem like a small number, but it's important to keep in mind that resistance can vary greatly depending on the material and conditions.

If you are still unsure about how to use your digital multimeter, I recommend checking the manufacturer's website or consulting a manual for more detailed instructions. You can also reach out to a fellow scientist or a lab technician for assistance. Remember, it's always better to ask for help than to damage your equipment or get incorrect results.

I hope this helps, and happy measuring!