Procedure for measuring ESP (External Static Pressure) at Fan In / Fan Out

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Procedure for measuring ESP (External Static Pressure) at Fan In / Fan Out

🔹 Step 1 : Prepare equipment
 • Manometer / Differential Pressure Gauge
 • Static Pressure Probe or Pitot Tube.
 • Hose + pipe plug

🔹 Step 2 : Select the measurement position for Fan In (suction side).
 • Measure at the air duct before entering the fan.
 • Suitable distance ≈ 1–2D from Inlet.
 • The pressure value will be negative (–).

🔹 Step 3 : Select the Fan Out measurement position (supply side).
 • Measure at the air duct behind the fan.
 • Optimal distance ≈ 2–3D from Outlet.
 • The pressure value will be positive (+).

🔹 Step 4 : How to measure and read values
 • Drill pipe holes Ø6–8 mm
 • Insert the probe perpendicular to the wind direction.
 • Zero gauge before measuring.
 • Save the value.
 • SP_in = –xxx Pa
 • SP_out = +yyy Pa

🔹 Step 5 : Calculate the actual ESP value\boxed{ESP = |SP_{in}| + |SP_{out}|}
Example in the picture
 • SP_in = –120 Pa
 • SP_out = +380 Pa
👉 ESP = 500 Pa

📌 Short memories for teaching/work
🔹 Measure static pressure before Fan + after Fan.
🔹 Do not measure on the fan.
🔹 Add the absolute values together = true ESP.Click here to type a system message.