Electrical power is the product of Potential (Voltage) and Current. Readings may fluctuate because the wind coming out of the fan is fluctuating. This can also be caused by blades that do not spin smoothly or change shape as they spin. Additionally, readings will be irregular if the blades are not balanced, evenly distributed, or are producing unequal amounts of drag.

The simplest method is to use the Go Direct® Energy Sensor (GDX-NRG) as power output is automatically calculated.

If you are using a current probe and a voltage probe rather than an Energy Sensor, you need to create a calculated column to measure the power output of the turbine.

Note: This procedure assumes you are using the 30-Volt Voltage Probe (30V-BTA) and High Current Sensor (HCS-BTA). You can also use the Differential Voltage Probe (DVP-BTA) and the Current Probe (DCP-BTA).

Create the calculated column in Logger Pro:

  1. Choose New Calculated Column from the Data menu.
  2. Enter Power as the Name and W as the Units. W is the abbreviation for watt, the unit of power.
  3. For the Expression, select Potential from the Variables (Columns) menu, type * (asterisk), and then select Current from the Variables (Columns) menu. Your expression should read “Potential”*”Current”.

If you want to measure power in horsepower, you can make another calculated column.

  1. Choose New Calculated Column from the Data menu.
  2. Enter Horsepower as the Name and hp as the Units.
  3. Select Power (the calculated column you just created) from the Variables (Columns) menu.
  4. Type / (forward slash), and then type 746. Your expression should read “Power”/746. This is because the most common electrical power conversion for horsepower is 1 hp = 746 W.

Create the calculated column in LabQuest App:

  1. Tap Table to view the Table tab and choose New Calculated Column from the Table menu.
  2. Enter Power as the Name and W as the Units. W is the abbreviation for watt, the unit of power.
  3. Select XY as the Equation Type.
  4. Select Potential as the Column for X and Current as the Column for Y.
  5. Adjust the Displayed Precision as you prefer.

If you want to measure power in horsepower, you can make another calculated column.

  1. Choose New Calculated Column from the Table menu.
  2. Enter Horsepower as the Name and hp as the Units.
  3. Select X/A as the Equation Type.
  4. Select Power (the calculated column you just created) as the Column for X and enter 746 as A. This is because the most common electrical power conversion for horsepower is 1 hp = 746 W.
Published: May 24, 2017. Updated: December 16, 2021.