1–20

Introduction to Variable-Frequency Drives

Getting Started

Intelligent Functions and Parameters

Much of this manual is devoted to describing how to use inverter functions and how to configure inverter parameters. The inverter is microprocessor -controlled, and has many independent functions. The microprocessor has an on-board EEPROM for parameter storage. The inverter’s front panel keypad provides access to all functions and parameters, which you can access through other devices as well. The general name for all these devices is the digital operator, or digital operator panel. Chapter 2 will show you how to get a motor running, using a minimal set of function commands or configuring parame- ters.

The optional read/write programmer will let you read and write inverter EEPROM contents from the programmer. This feature is particularly useful for OEMs who need to duplicate a particular inverter’s settings in many other inverters in assembly-line fashion.

Braking

In general, braking is a force that attempts to slow or stop motor rotation. So it is associated with motor deceleration, but may also occur even when the load attempts to drive the motor faster than the desired speed (overhauling). If you need the motor and load to decelerate quicker than their natural deceleration during coasting, we recommend installing an optional dynamic braking unit. See “Introduction” on page 5–2 and “Dynamic Braking” on page 5–5 for more information on the BRD–E2 and BRD–EZ2 braking units. The L100 inverter sends excess motor energy into a resistor in the dynamic braking unit to slow the motor and load. For loads that continuously overhaul the motor for extended periods of time, the L100 may not be suitable (contact your Hitachi distributor).

The inverter parameters include acceleration and deceleration, which you can set to match the needs of the application. For a particular inverter, motor, and load, there will be a range of practically achievable accelerations and decelerations.