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Nulling your leadsWhy null every single time?

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This is the one step that quietly ruins readings. With crocodile clips on the ends, set to continuity, press test and the meter shows 0.2 Ω — that is the leads alone. Press the null button, test again, and it reads zero with null shown on the display.

Nulling, in order

1. Clips on, fixed jaw to fixed jaw — not moving jaw to moving jaw.
   The fixed jaws grip harder and give a better reading.
2. Set the dial to continuity.
3. Press test  -> reads the resistance of the leads (about 0.2 Ω).
4. Press null, press test again -> reads zero, display says null.
5. Now your r2 or R1 + R2 reading is the circuit, not the leads.
✋Null it every time you use it. Even if the display still says zero from last time. Copper always has resistance, and after the meter has been off for a few days that resistance comes back into the reading. A meter left for a few days will have re-acquired that 0.2 Ω.
Leads are mostly universal. You are not stuck with the ones that came with the kit. Brown and green are the habit for continuity — brown for r1, green for r2.
0.2 Ω the leads alone before nulling null 0.00 Ω NULL on the display ready to test fixed jaw to fixed jaw the fixed jaws grip harder and give the better reading
0.2 Ω of lead resistance is enough to make a sound bonding conductor read wrongly. Null first, and re-null if you change function.

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