Enter the cable run/length (m), the current (amps), and the voltage drop per ampere meter (V/amp-m) into the Voltage Rise Calculator. The calculator will evaluate the Voltage Rise. 

Voltage Rise Formula

The following formula is used to calculate the Voltage Rise. 

Vr = L*I*Vd / 1000


  • Vr is the Voltage Rise (volts)
  • L is the cable run/length (m) 
  • I is the current (amps) 
  • Vd is the voltage drop per ampere meter (V/amp-m) 

To calculate a voltage rise, multiply the cable length by the current, multiply this result by the voltage drop per ampere meter, then divide by 1000.

How to Calculate Voltage Rise?

The following steps outline how to calculate the Voltage Rise.

  1. First, determine the cable run/length (m).
  2. Next, determine the current (amps). 
  3. Next, determine the voltage drop per ampere meter (V/amp-m). 
  4. Next, gather the formula from above = Vr = L*I*Vd / 1000.
  5. Finally, calculate the Voltage Rise.
  6. After inserting the variables and calculating the result, check your answer with the calculator above. 

Example Problem:

Use the following variables as an example problem to test your knowledge.

cable run/length (m) = 100

current (amps) = 30

voltage drop per ampere meter (V/amp-m) = 250

Vr = L*I*Vd / 1000 =  ?