The Allen-Bradley 5250MLP3 is an AC Drive that features applications, some of which use non-standard motors or motors which require independent control for the load frequency and the voltage. The applications include induction heating, resistive loads, vibration welding, power supplies, electromagnetic stirring, and vibratory feeders or conveyors. The standard control modes have been calibrated in volts per hertz. These standard control modes have boost selections, fans, speed feedback selection, pumps, and flux vectors with encoder less modes and encoders. The user must maintain the relationship between the variable frequency inverter and the control of the output voltage in terms of nonlinear (overmodulation) and linear regions.

The voltage linearity of the 5250MLP3 AC drive can be achieved through the maintenance of a constant voltage to frequency ratio. This voltage should be maintained throughout the whole operating region. The function of the variable frequency inverter contained in this drive is to deliver an adjustable-frequency alternating voltage. The magnitude of the alternating voltage should be related to the 5250MLP3’s output frequency. The control has the capability of compensating for lost voltage as the linear-to-nonlinear transition begins. The control, therefore, delivers a linear output voltage profile.

The 5250MLP3’s adjustable voltage control mode operation allows for separate control of the output frequency and the output voltage which is vital for applications that are basically non-motor types. The voltage frequency components come with independent acceleration and deceleration rates and also independent references. Both the frequency and the voltage are adjustable within their respective ranges at any point. The adjustable voltage control provides either a single-phase output voltage or a three-phase output voltage, but the drive is not designed to operate in single-phase motors in a single-phase mode.