What are the Electrical Requirements for an Agitator?

This will no doubt be one of the most asked questions by any electrical contractor bidding for your distillery build-out. And the answer is: It depends.

Thank you for coming to my TED talk. Next week we will be discussing the origin of the word “depends”.

Seriously though, let’s start with tank sizing and the specific task the tank will be used for. To do this let’s take a step back even further and determine what kind of production goals you have in mind. Let’s start at the end. The end of the day, the month, or the end of the year? That is up to you.

The Basic Electrical Requirements for an Agitator:

For the sake of this discussion, we’ll go with the smallest kettle that we feel is needed to make money right out of the gate. The 1000L kettle.

As a general rule, the StillDragon 1000L distillation kettle is outfitted with a 1.5kw / 1700 rpm agitator motor and a gear reduction transmission that has a 30/1 reduction ratio. This means that for every time the agitator motor spins 30 times, the agitator paddle will spin once. The gear reduction helps ensure that the motor is functioning with minimal stress. I digress.

 The motors are set up as NEMA-rated explosion-proof motors that use 3 phase power. However, 3 phase power is not a requisite. By adding a variable frequency drive (VFD) to the agitator motor, it is possible to run the 3 phase motor on single-phase power.

With 3 phase power, the 1.5kw motor only draws 5.15 amps at 240 volts and 2.57 amps at 480 volts.

When running the 3 phase motor (via VFD) on single-phase (240 volts) power the amp draw will be 9.11

By comparison, a 5 kW / 3 phase / 240volt motor will draw 17.18 amps. And when running the same motor (via VFD) on single-phase power the draw will be 30.41 amps.

All of this can sound confusing to the average layperson. The good news is that all we really need to do is provide your electrical engineer or contractor with a photo of the motor spec plate that will be mounted to the frame of the motor. The spec plate contains all of the information needed to help your electrical contractor calculate the total supply of power to your agitator.