### "Constant Voltage" Transformer Power Delivered

 Power Driven on Line watts Length of Line ft. Voltage level volts Wire Gauge #10 AWG #12 AWG #14 AWG #16 AWG #18 AWG #20 AWG #22 AWG #24 AWG Line Loss: dB

This calculator provides line loss with 2-conductor cable
on a constant voltage line.

Equation used to calculate the data:

Ploss = 10 * Log [1 - ((2 * RL) / (2 * RL + (Vline squared / Prated))]

RL = (Rref / 1000) * D

Where:
D = length of wire used

Ploss = ower loss in dB

Prated = power driven on line
RL = wire guage resistance
Vline = voltage on line

Many people don't realize that a transformer labeled for use with a specific voltage will work just as well at other voltages. This calculator provides power delivered from a transformer tap when driven with other than the rated voltage.

Example: You are installing a distributed system with very long lines. To overcome line loss, you select a 140 volt system. Which transformer tap will feed 10 watts to a loudspeaker with a "70V transformer?

1. Enter values for both "Voltage Rating of Transformer" and "New Voltage"

2. Either:

• Enter a value for "Tap Rating" to calculate the power output from the tap at the new voltage.
• Enter a value for "Power from Tap" to calculate the correct transformer tap to achieve the desired power at the new voltage.

Equation used to calculate the data:

Pactual = (Vnew squared / Vrated squared) * Prated

Where:
Prated = transformer tap value
Pactual = new power from tap
Vrated = voltage rating of transformer
Vnew = new voltage