Voice coil resistance testing

[Donald]

I plan to post a bunch of cone sets and plan to include a picture of the DC resistance reading.

I have a L8RLE52 cone and can’t get a steady reading. Just tried a D16R2420 and the same thing happens.

I have alligator clip type probes so I am getting a good connection to the coil leads. I put a fresh battery into my Fluke 77. Just sitting on the table the reading changes from 5.7 to 6.3 ohms. I shorted the leads and the reading varied from 0 to .2 ohms. I am using Fluke test leads and Fluke probes.

1. Is the DC resistance important to selling cones?
2. Is this varying reading normal at low values?

[Earl K]

I plan to post a bunch of cone sets and plan to include a picture of the DC resistance reading.

I have a L8RLE52 cone and can’t get a steady reading. Just tried a D16R2420 and the same thing happens.

I have alligator clip type probes so I am getting a good connection to the coil leads. I put a fresh battery into my Fluke 77. Just sitting on the table the reading changes from 5.7 to 6.3 ohms. I shorted the leads and the reading varied from 0 to .2 ohms. I am using Fluke test leads and Fluke probes.

1. Is the DC resistance important to selling cones?
2. Is this varying reading normal at low values?

Yes, seeing/knowing the dcr is important to me ( though I'm not a potential buyer here ).

The dcr reading should quickly stabilize ( under firm contact pressure ) and not vary by more than what the shorted leads indicated.

I'd say either your meter is on the fritz or your measurement techniques are in doubt. :blink:

Do you have a second meter that you could try out? ( second opinions are always useful ) :eek:



:)

[grumpy]

test value of a small value resistor... same issue?

holding coil still, not near metal or magnets?

if you test for voltage instead, do you see a small value bobbing about?

[Donald]

Smallest resistor I could find was 10k. Fluke measured 10.03 and 10.04k. No name cheap meter measured 10.02 and 10.03k.