Danfoss VLT AutomationDrive FC 300 Design Guide

3.2.1 Control Principle
An adjustable frequency drive rectifies AC voltage from line power into DC voltage, after which this DC voltage is converted
into AC power with a variable amplitude and frequency.
The motor is supplied with variable voltage/current and frequency, which enables infinitely-variable speed control of three-
phased, standard AC motors and permanent magnet synchronous motors.
130BC514.12
3-phase
power
input
DC bus
Motor
Brake
resistor
88 (-)
89 (+)
95
PE
93 (T/L3)
92 (S/L2)
91 (R/L1)
(R-) 81
(R+) 82
(PE) 99
(U/T1) 96
(V/T2) 97
(W/T3) 98
Figure 3.1 Control Principle
The control terminals provide for wiring feedback, reference, and other input signals to the following:
•
Adjustable frequency drive
•
output of adjustable frequency drive status and fault conditions
•
relays to operate auxiliary equipment
•
serial communication interface
Control terminals are programmable for various functions by selecting parameter options described in the main menu or
the quick menus. Most control wiring is customer supplied unless factory ordered. A 24 V DC power supply is also provided
for use with the adjustable frequency drive control inputs and outputs.
Product Introduction Design Guide
22 Danfoss A/S © Rev. 2014-02-10 All rights reserved. MG34S222
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Danfoss VLT AutomationDrive FC 300 Specifications

General

Brand	Danfoss
Model	VLT AutomationDrive FC 300
Category	DC Drives
Language	English