Hammond Drive Isolation Transformers

Drive Isolation Transformers are transformers that are designed to endure mechanical stresses, voltage distortions, and harmonics that are associated with silicon-controlled rectifiers. These transformers provide power to AC and DC variable speed drives.

The main function of a Drive Isolation Transformer is to supply electrical isolation between the power source and the drive system.

To size a drive isolation transformer, you must know the power output (KVA) of each axis. To find this, calculate the horsepower for each axis and convert the horsepower into watts. If you are providing power to more than one motor, add the KVA together to get a system KVA total.

The formula to find the transformer KVA rating is:

• Transformer KVA Rating = (Sum of the average output power of each motor) X Power Factor
• OR KVA = ((RPM x Torque)/63025)) X (746W/HP) x (KW/1000W) x Power Factor
• *Use a Power factor of 2 for single phase, and a power factor of 1.5 for three phase models