i was checking for some informations on a catalogue of a device measures the internal coating of aluminum tube
there is some informations i didnt get how to measure it:
Voltage and measuring interval : 4500 mv
2.5s
which its ok by providing 4.5v dc for 2.5 seconds
internal resistance: Voltmeter 20kOhm/v
Ammeter 2.5Ohm at 100ma
what they mean by this & how i can measure this to provide my measurements ?
i have used ina219 Current sensor for reading the current of the tube
20 kOhm/Volt is a spec for traditional analog VOM's describing overall quality. In other words they used a reasonably good instrument.
Their ohm reading suggests they measured 2.5 ohms on their lowest range Rx1.
I say this because when I test ohms on my VOM lowest range Rx1, it sends 60 mA through the leads. The battery is 1.5V. Therefore I suppose their ohmmeter sends 100mA, not much different.
However you mention 4.5 V, but then I can't picture how that yields 100 mA and 2.5 ohms.