Electronic Bypass Option Overview; General Description - Siemens SED2 VFD Operating Instructions Manual

SED2 VFD Electronic Bypass Option Operating Instructions

Electronic Bypass Option Overview

General Description

During normal operation in a typical
application, the input and output
contactors close and the SED2
operates the motor (Figure 1). The
bypass contactor provides the ability to
operate the motor on utility power and
eliminate the SED2 from the motor
control circuit. The SED2 Electronic
Bypass Option also allows you to select
features that enhance the control of the
contactors and the outputs that report
operation.
The SED2 Electronic Bypass Option
consists of a SED2 VFD, and a bypass
enclosure with electronic controls
(Figure 2). The electronic controls
include:
•
Controller board
•
Keypad
•
Step-down power transformer
•
Contactors:
−
Bypass
−
Output
−
Input (optional)
•
Overload (current) relay
•
Reactor (optional)
•
Disconnect switch (or optional
circuit breaker)
•
Fuses (optional)
•
Cable harnesses
4
BYPASS
CONTACTOR
INPUT
CONTACTOR
Figure 1. Functional Block Diagram of
Typical Electronic Bypass Option.
CONTROLLER
BOARD
KEYPAD
(DOOR
MOUNTED)
STEP-DOWN
POWER
TRANSFORMER
OUTPUT
CONTACTOR
BYPASS
CONTACTOR
OVERLOAD
(CURRENT)
RELAY
Figure 2. Typical SED2 Electronic Bypass Option
Components.
OVERLOAD
RELAY
VFD
OUTPUT
CONTACTOR
SED2 VFD
INPUT
CONTACTOR
REACTOR
(OPTIONAL)
DISCONNECT
SWITCH
(OR OPTIONAL
CIRCUIT BREAKER
SHOWN)
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