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Diode mode, conduction mode
- Thread starter jxx
- Start date
The multimeter can only measure the voltage between component pins.
It injects a constant current, which creates a voltage across the component, V=IxR.
For a pure resistor (pasive component) is very simple, you get exact ohm value R=V/I, after some transformations inside the multimeter.
Keep in mind, the multimeter measures the voltage over the resistor, not its ohm value directly!
For diode mode is used another current value; that's the reason you get distinct reading than in ohm scale.
Non linear behavior of diodes, transistors, or any active components create high range values.
The multimeters show "V" at the end scale in this case.
However, I strongly recommend, do NOT post that on diode mode readings; avoid misunderstoods with pure voltage readings.
When testing capacitors, the reading varies a lot.
An (initial) empty capacitor tries to get the max injected current; like a short, or very low resistance.
However, that parasitic resistance increases rapidly and current drops a lot.
Its capacitance requires another method to measure; based on the time to charge it until specific porcentage (with constant current).
If you need personal training, please contact Rossmann staff.
That can be done through other networks.
The forum goal is to help with repair assistances.
It injects a constant current, which creates a voltage across the component, V=IxR.
For a pure resistor (pasive component) is very simple, you get exact ohm value R=V/I, after some transformations inside the multimeter.
Keep in mind, the multimeter measures the voltage over the resistor, not its ohm value directly!
For diode mode is used another current value; that's the reason you get distinct reading than in ohm scale.
Non linear behavior of diodes, transistors, or any active components create high range values.
The multimeters show "V" at the end scale in this case.
However, I strongly recommend, do NOT post that on diode mode readings; avoid misunderstoods with pure voltage readings.
When testing capacitors, the reading varies a lot.
An (initial) empty capacitor tries to get the max injected current; like a short, or very low resistance.
However, that parasitic resistance increases rapidly and current drops a lot.
Its capacitance requires another method to measure; based on the time to charge it until specific porcentage (with constant current).
If you need personal training, please contact Rossmann staff.
That can be done through other networks.
The forum goal is to help with repair assistances.