Bypass Overview; General Description; Operation Overview - Siemens BT300 Operator's Manual

Bypass Overview

General Description

Bypass Overview
General Description

Operation Overview

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Siemens Industry, Inc.
During normal operation in a typical application, the input contactor (optional) and
output contactor close and the BT300 Drive operates the motor.
During bypass operation, the bypass contactor provides the ability to operate the motor
on utility power and eliminate the BT300 Drive from the motor control circuit.
Figure 1: Bypass Contactor Options.
The Siemens BT300 Bypass consists of a BT300 Drive and a bypass enclosure with
controls that include the following:
● Control terminals
● Operators (conventional only):
– "Drive-Off-Bypass" switch
– "Bypass On" light
– "Drive Test On-Off" switch (optional)
● Step-down control transformer
● Contactors:
– Bypass (M1)
– Output (M2)
– Input (M3) or Service Switch
● Overload (current) relay
● Disconnect with fuses, or circuit breaker
● Diagnostics board
● Drive Mode
– Drive input contactor (M3) or selector switch closes.
– Drive output contactor (M2) closes.
– The motor is controlled by the BT300 Drive output.
● Local Bypass Operation
– Requires a jumper between the bottom two pins (LOC) of jumper block J7 on
the Bypass Diagnostic Board. This is the default jumper position from the
factory.
– "Off" opens the drive output contactor and the bypass contactor.
BT300 Bypass Operator's Manual DPD01391
2016-08-05