Introduction; Purpose Of The Manual; Overview - Danfoss VLT FC Series Operating Instructions Manual

Introduction

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1 Introduction

1.1.1 Purpose of the Manual

This manual provides detailed information for the instal-
lation and operation of the vertical panel used in
conjunction with a Danfoss variable frequency drive (VFD).
To enable efficient handling of the equipment,
requirements are provided for installation of:
•
mechanical
•
electrical
•
control wiring
•
proper grounding
•
environmental considerations
Pre-start and start up procedures are detailed. Also
included is a detailed overview of the panel bypass
function. In addition, identification of other optional
components and their operation and start up trouble-
shooting instructions are included. For the electronically
controlled bypass, additional programming and operation
information is provided.
1.1.2 Warnings, Cautions and Notices
Symbols
The following symbols are used in this manual.
WARNING
Indicates a potentially hazardous situation which, if not
avoided, could result in death or serious injury.
CAUTION
Indicates a potentially hazardous situation which, if not
avoided, may result in minor or moderate injury. It may
also be used to alert against unsafe practices.
CAUTION
Indicates a situation that may result in equipment or
property-damage-only accidents.
NOTE
Indicates highlighted information that should be regarded
with attention to avoid mistakes or operate equipment at
less than optimal performance.
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Option Panel Operating Instructions

1.1.3 Overview

A variable frequency drive regulates the speed and
operation of an electric motor(s). The drive is
programmable and offers many features and savings
compared to operating a motor from unregulated line
voltage. The panel is a protective enclosure in which the
drive and various optional components are assembled and
mounted. One of the most common functions of the
standard bypass/non bypass panel is to allow switching
between VFD control and running in bypass. In bypass, the
motor is operated directly from line input power.
Two types of bypass options are available:
•
•
The EMB is operated by selector switches on the front of
the panel. The EMB controls a motor(s) by switching
between drive control, operation in bypass, or off. In
addition, a test setting is available which disengages the
motor from the drive but keeps the drive operational while
the motor runs in bypass. The switching function activates
contactors that open or close to provide power to the
motor through the drive or bypass circuitry, as required.
The ECB also uses contactors to provide power to the
motor through the drive or bypass circuitry. However, the
ECB contains a local processor which interacts with the
drive's control logic for programmable options, remote
inputs, and status reporting. The VFD's logic circuitry is
backed up by an independent panel-mounted power
supply so that, even if the drive loses power, control and
communication functions are maintained. Programming
and display are provided by the VFD's keypad. An
important feature of the ECB is the ability to accept
commands from a building automation system (BAS) and
to report operational status in return.
See more detailed descriptions of the EMB in 5 Electrome-
chanical Bypass (EMB) Operation and 6 Electronically
Controlled Bypass (ECB) Operation.
®
MG14I102 - VLT is a registered Danfoss trademark
electromechanical bypass (EMB)
electronically controlled bypass (ECB)