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Old 9th November 2019, 15:20   #1
macafee2
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Default How to read this multi meter

I'm sure I'm going to get humiliated for being stupid but it is a risk I have to take because right now, I don't have a clue.
There are 3 pictures below, the instructions and 2 readings both of the same thing but with the multi meter set to different scales.

What on earth are the ohms reading in the two pictures where different scales have been selected?
Although the readings are of the same thing, the readings could be different as it was saliva on my finger but nevertheless how many ohms is each one?

If the scale selected had been 200 and I had a reading of .5 how many ohms would it be?
Also from the instructions what does resolution mean? Increment?



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Attached Images
File Type: jpg instructions.jpg (126.1 KB, 36 views)
File Type: jpg 200k scale.jpg (125.1 KB, 47 views)
File Type: jpg 2 meg scale.jpg (128.0 KB, 43 views)
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Old 9th November 2019, 16:24   #2
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200k scale reading is 117600 ohms
2meg scale reading is 412000 ohms

Resolution is the smallest value each scale will indicate. As the scale has 4 digits the last digit (on the right)is the resolution.
For example on the 200 ohm range a reading of 100.1 is 100.1 ohms. The figure will only change by 0.1 ohms as shown in your first image.
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Old 9th November 2019, 17:17   #3
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200k scale reading is 117600 ohms
2meg scale reading is 412000 ohms

Resolution is the smallest value each scale will indicate. As the scale has 4 digits the last digit (on the right)is the resolution.
For example on the 200 ohm range a reading of 100.1 is 100.1 ohms. The figure will only change by 0.1 ohms as shown in your first image.
magic thank you dattrike appreciate it.
once more question If the scale selected had been 200 and I had a reading of .5 how many ohms would it be? 5?

when did resolution become increment?

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Old 9th November 2019, 17:36   #4
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magic thank you dattrike appreciate it.

once more question If the scale selected had been 200 and I had a reading of .5 how many ohms would it be? 5?



when did resolution become increment?



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0.5 will be half an ohm on the 200 scale
As the meter reads 0.1 increments on that range i.e it will only read 0.1, 0.2 etc then that is also the lowest resolution of the meter.
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Old 9th November 2019, 17:43   #5
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If the scale selected had been 200 and I had a reading of .5 how many ohms would it be? 5?
No, it would be 0.5 ohms.
You'll note that the 200 ohm range can display tenths of an ohm. It will therefore show a decimal point and you will get a reading of whole ohms and tenths of an ohm.

The kilohm ranges, for example 200k, will show readings in kohms. For example 150kohms will be displayed as 150 and will only change every 100 ohms. So the next highest possible reading would be 150,100 ohms or 150.1 on the display.

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Old 9th November 2019, 17:53   #6
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No, it would be 0.5 ohms.
You'll note that only the 200 ohm range can display tenths of an ohm. It will therefore show a decimal point and you will get a reading of whole ohms and tenths of an ohm.

The kilohm ranges, for example 200k, will show readings in kohms. For example 150kohms will be displayed as 150 and will only change every 100 ohms. So the next highest possible reading would be 150,100 ohms or 150.1 on the display.

Simon
Thanks Simon, much clearer than my explanation.
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Old 9th November 2019, 17:56   #7
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Thanks Simon, much clearer than my explanation.
Sorry for jumping in on your replies David. I thought that you were off-line at the time and that Ian might be waiting for an answer. Then we both ended up typing at the same time and unaware of that. I'm glad that you like my wording, thank you!

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Old 9th November 2019, 20:51   #8
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I am going to have to write this down so I don't forget. Thank you for the explanations I do appreciate it.

I may have to resurrect this thread at some point, when I measure via the 200meg, 20k and 2k ranges

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Old 10th November 2019, 09:46   #9
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... when I measure via the 200meg, 20k and 2k ranges ...
The highest range you have Ian is 2MΩ but you're extremely unlikely to need that in automotive fault finding! Any reading in the megohm range will suggest an open, or break in the path you're measuring.

For continuity checks, use the 200Ω range. You're looking for a reading very close to zero. Remember that when measuring resistance, the car battery should be disconnected and the circuit you are measuring should be broken. In other words, when checking the resistance of the automatic gearbox solenoid valves, the connector must be separated first.

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Old 10th November 2019, 09:55   #10
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not sure why trying to understand the readings has blown my mind.
I should have stuck with my old meter with a needle

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