Since a while I have a Fluke 87V meter (bought new, was around 600€). Actually haven't used it a lot yet.
It came with a nice set of TL175 TwistGuard test leads. These leads alone cost around 60€ when bought separately.
The Twist Guard thing means that the exposed length of the tip can be varied by twisting the probe shell.
A few days ago I wanted to measure some speaker DCR and got nonsense readings.
Way too high and not repeatable.
With shorted tips the meter reading was above 20R and changing.
I measured the resistance of each lead using my PeakTech LCR meter with Kelvin clamps and got somewhat different readings for the leads but both around 10R.
Typically I expect a good test lead to have a resistance of 0.1R max.
A then found out that operating the twisting mechanism a few times tended to lower resistance by a few Ohms.
So I figured that there must be some sliding contact in the probe. Maybe dirty or corroded
I worked some D5 into the probes from the tips and after a couple of hours and more twisting the resistance per lead finally dropped to 0.1R showing that the leads themselves are good.
So a meter reading of 0.2R with shorted tips now.
Acceptable - but reliable?? Not sure.
Very disappointed of Fluke and the quality of the new and barely used test leads.
https://www.fluke.com/en-us/product/...ds/fluke-tl175
It came with a nice set of TL175 TwistGuard test leads. These leads alone cost around 60€ when bought separately.
The Twist Guard thing means that the exposed length of the tip can be varied by twisting the probe shell.
A few days ago I wanted to measure some speaker DCR and got nonsense readings.
Way too high and not repeatable.
With shorted tips the meter reading was above 20R and changing.
I measured the resistance of each lead using my PeakTech LCR meter with Kelvin clamps and got somewhat different readings for the leads but both around 10R.
Typically I expect a good test lead to have a resistance of 0.1R max.
A then found out that operating the twisting mechanism a few times tended to lower resistance by a few Ohms.
So I figured that there must be some sliding contact in the probe. Maybe dirty or corroded
I worked some D5 into the probes from the tips and after a couple of hours and more twisting the resistance per lead finally dropped to 0.1R showing that the leads themselves are good.
So a meter reading of 0.2R with shorted tips now.
Acceptable - but reliable?? Not sure.
Very disappointed of Fluke and the quality of the new and barely used test leads.
https://www.fluke.com/en-us/product/...ds/fluke-tl175
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