Data Sheet for Product

Submittal Sheet
Document No. 154-062
May 9, 2011
SED2 VFD NEMA Type 3R and
Type 3R Harsh Environment (3RHE) Bypass
Siemens Industry, Inc.
Description
The NEMA Type 3R Bypasses are companion packages for
the family of SED2 Variable Frequency Drives (VFD). NEMA
Type 3R/3RHE enclosed bypasses are manufactured for
outdoor locations that are not in direct sunlight.
Two primary styles of 3R cabinets are provided. The
standard 3R rating provides protection from falling rain to the
enclosed SED2 VFD and electrical control components. The
harsh environment 3R rating is identical to the standard, but
it is supplied with a more robust NEMA 12 SED2 drive
suitable for corrosion and coastal environments.
A heater is supplied in the Type 3R models to protect
against condensation. The standard package is rated to
104°F (40°C). A high temperature package, rated to 122°F
(50°C), is available.
The SED2 is designed specifically for HVAC applications
and supports a variety of digital and analog I/O and provides
built-in PID features to control pumps and fans. For
information on the family of SED2 VFDs, see the SED2
Variable Frequency Drives Submittal Sheet (154-042).
Features
Bypass Power
3-Contactor: Input, Output and Bypass
− Overload protection in bypass mode.
− Step-down transformer with fused primary and
secondary.
− Contactors electrically and mechanically
interlocked.
− Drive test function.
− Complete electrical isolation of drive.
Input Device
− Fused disconnect.
− All doors are interlocked and padlockable.
Reactor Options
− Line reactor mounted in bypass enclosure.
− Line reactor supplied separately (in NEMA
Type 3R enclosure).
− Load reactor (in NEMA Type 3R enclosure)
supplied separately.
Bypass Control
Auto Bypass
− Relay logic allows user to send the motor to
bypass mode based on the drive’s
programmable relay.
Enable Input
− Generally used for safety tie-ins; the motor will
not operate the drive or bypass when open.
Common Remote Start/Stop
− Can be used in both drive and bypass mode.
Essential Services Mode
− Typically used for smoke purge; the motor
goes to bypass regardless of the selected
mode.
− No call to stop will have an effect, including
open safety or stop commands.
− Only turning the power off or opening this
contact will stop the motor.
Bypass – Door Mounted Control Devices
− Drive-Off-Bypass selector
− Bypass pilot light
− Drive Test On-Off selector