22 replies to this topic

[jiminwatford]

Following what AC Dodd says in this video https://youtu.be/Vnv...MCSqpzWQmiHC1V4 i wanted to test the ohm reading on my coil So i bought a multimeter from Screwfix and can't get a reading

 

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There is an ohm symbol there but no reading shows

 

I'm either doing it wrong or the multimeter is not right for it

[sonscar]

Set to ohms and touch the leads together and you should get zero.The display lights up?Steve..

[jiminwatford]

Set to ohms and touch the leads together and you should get zero.The display lights up?Steve..

Yes i get a zero reading when doing that

 

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[bpirie1000]

Have you still got the instructions for the multimetre?

[jiminwatford]

Have you still got the instructions for the multimetre?

 

Yes but i don't know what i'm looking at / for. I've never used a multimeter before and am very unfamiliar with them

[stuart bowes]

presumably if you get any bit of random cable, the longer the better, you'll get some sort of reading measuring between both ends

 

far as I'm aware there should be nothing more complicated to it than putting one probe at each end and numbers come up .

 

though I'm not a qualified sparkie I have used them numerous times.  mostly I get ohms readings when I forget to switch mine over to the continuity setting - the next setting along like the wifi symbol, should buzz when you touch them together (which you should be able to use to check your leads aren't duff)

Edited by stuart bowes, 26 February 2024 - 08:03 PM.

[jiminwatford]

I'm wondering if this multimeter is right for the job

 

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the coil should read 0.8 ohms and i don't think the multimeter goes down that far?

 

When i put the positive lead into the centre of the coil (and the black to the negative) it reads 10.06 and there is always a little 'K' on the screen. So that's 10 thousand ohms?

 

I can't seem to get rid of the 'K' so it just reads them singly rather than in thousands

[jiminwatford]

My conclusion is it won't read low enough. So i have ordered one of these https://www.ebay.co....mCondition=1000

 

'Measuring Resistance Range: 0~99.99MΩ'

[Spider]

When measuring Coils, they are in a way, similar to Capacitors, they take time to charge and settle down to a stable reading of the actual DC Ohmic resistance of the coil. Connect it up and depending on the meter, you might need to leave it as long as a minute to get a proper reading.

[Steam]

You really need a range of 200 Ohm to check low resistance.

[jiminwatford]

You really need a range of 200 Ohm to check low resistance.

 

The one i have ordered has a Measuring Resistance Range: 0~99.99MΩ

 

I think it has a 200 ohm section?

 

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[Lplus]

 

You really need a range of 200 Ohm to check low resistance.

 

The one i have ordered has a Measuring Resistance Range: 0~99.99MΩ

 

I think it has a 200 ohm section?

 

s-l1600.jpg

 

yes, at 6 o'clock

[sonscar]

It obviously can go down that far as it is possible to read zero with it.from pos to neg should be a few ohms and from center to neg should be thousands( I think)Steve..

[stuart bowes]

seems to me the original one should have been fine on the 2kohm setting, if it has a resolution of 0.001 - using the available 4 digits in that position your 0.8 ohms would read 0.800

 

in the 20kohm setting it would read 00.80

 

in the 200kohm setting it would read 000.8

 

that's not to say the meter itself isn't duff or poorly calibrated of course

 

did you confirm the leads were ok using the continuity test

 

bit moot now I suppose if you already ordered new

Edited by stuart bowes, 27 February 2024 - 10:26 AM.

[jiminwatford]

seems to me the original one should have been fine on the 2kohm setting, if it has a resolution of 0.001 - using the available 4 digits in that position your 0.8 ohms would read 0.800

 

in the 20kohm setting it would read 00.80

 

in the 200kohm setting it would read 000.8

 

that's not to say the meter itself isn't duff or poorly calibrated of course

 

did you confirm the leads were ok using the continuity test

 

bit moot now I suppose if you already ordered new

 

I don't know if it allows me to manually adjust the settings. I think it measures the resistance and decides which setting to display it in. On the coil it shows 0.001. When touching just the leads together it shows 0.000