Skip to content

✅ MSO5000 Live Monitor — Power Analysis Setup Checklist AC

🔌 For Grid Power Measurement with Differential Current Probe (High-Voltage AC)

🧰 Hardware Assumptions

  • Voltage probe: CH1 — measures 230V AC (grid voltage)
  • Current probe: CH4 — differential current probe with attenuation (e.g. 5×), placed around load/live wire
  • Scope type: RIGOL MSO5000
  • Load type: AC (resistive or reactive), 50Hz
  • Direction: Current flows into the load (positive power)

🛠 Oscilloscope Setup (on RIGOL MSO5000)

CH1 — Grid Voltage

  • Connect across L–N (line to neutral)
  • Set unit: VOLT
  • Set probe: 1X (or 10X depending on your voltage probe)
  • Enable 20MHz BW Limit ✅ (filters noise, improves PF accuracy)

CH4 — Grid Current (Differential Probe)

  • Connect current probe around line wire
  • Set unit: AMP ✅ (crucial!)
  • Set probe: 5X (match your differential probe attenuation)
  • Enable Invert ✅ (if current direction is flipped — makes power positive)
  • Enable 20MHz BW Limit ✅ (stabilizes power factor and FFT phase)

⚙️ Live Monitor: Power Analysis Tab Setup

Field Value / Action Why
Voltage Ch 1 CH1 measures grid voltage
Current Ch 4 CH4 measures current
Correction Factor 1.0 No scaling needed — scope already shows real amps
Current Probe Type Clamp ✅ Internally handled as unit = AMP
Probe Value 1.0 ⚠️ Leave at 1.0 → no further scaling
DC Offset ❌ Usually off Optional — turn on if baseline is offset
25M [v]/[i] ❌ Off Not needed for 50Hz AC
➤ ⚡ Measure Click to start Done ✅
  • ✅ Vrms should be around 230V
  • ✅ Irms should match what clamp/differential probe shows
  • ✅ Real Power (W) should be positive (if direction is correct)
  • ✅ Apparent Power (VA) = Vrms × Irms
  • ✅ Power Factor matches scope (~0.04 for small reactive loads)
  • Use 📈 Plot Last to view PQ triangle with S/P/Q vectors

⚠️ Notes on Accuracy

Case What to Do
Current reads negative ✅ Enable Invert on CH4
Power is 10× too low ✅ Check probe setting: 5X vs 1X
PF is unstable ✅ Enable BW Limit on CH1 & CH4
Scope reads wrong amps ✅ Make sure CH4 unit = AMP

✅ Why This Setup “Just Works”

Because CH4 is set to AMP and the scope knows the probe attenuation (5X), both the Rigol and Live Monitor treat the data as real-world Amps, no manual scaling needed.

Inversion, probe setting, and unit type are all respected by both systems — so the numbers match perfectly.

🏁 Quick Reference Table

Signal CH Scope Unit Probe Setting GUI Probe Type GUI Probe Value
Grid Voltage 1 VOLT 1X or 10X — —
Grid Current 4 AMP 5X Clamp 1.0

🧠 If Rigol PQ and Live Monitor match exactly — you're doing it right.