AS hose resistance measurement data

[todd_fuller]

Long story short, I didn't want to shell out the $$$ for a UDD to keep my CT from getting zapped by a static discharge. I picked up the static conductive Dust Deputy cyclone to supplant my existing non-antistatic cyclone. In the process, I learned is pretty difficult to find affordable conductive hose. In the process, I bought a cheap $40 insulation resistance tester so I could actually determine if I was achieving my goal of maintaining a path to ground. Since I made these measurements, I thought I'd share them with the general community.

Standard CT Midi hose
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36mm hose from the workshop cleaning kit
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$70 Nilfisk 1-1/4" AS hose  (I was actually able to read this resistance with my Fluke DMM)
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Flexuast 2" (Got this due to Amazon pricing algorithm, paid $75 for 25')
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The Flexuast cuffs were very conductive, less than 0.1MOhm.
The black, static conductive Dust Deputy is very conductive as well, less than 0.1MOhm.

 

[Svar]

Why 15 fold difference between two Festool hoses? Seem to be the same length. Is the 90 deg. elbow not conductive? Considering that you coil the hoses the sleeves must be good insulators to yield good data.

 

[todd_fuller]

Your guess is as good as mine. The braided sleeve is non conductive. You can measure resistance of the festool hose itself with a normal DMM but the elbow is much less conducive and only the insulation resistance meter would get a reading.

 

[Bohdan]

The reading of conductivity of an antistatic hose can vary with the voltage at which the reading it taken. Usually the higher the voltage the higher the conductivity.

It actually doesn't matter what the reading is, it only needs to be below a certain value at a certain voltage, which is specified in the standard that the product conforms to.