Electronic Bypass Features And Functions; Input Power - ABB ACH 400 User Manual

Chapter 2 – Overview of ACH 400 with Electronic Bypass
Electronic Bypass
Features and Functions

Input Power

Door Interlocked
Disconnect Switch
Door Interlocked
Circuit Breaker
Drive Input Fuses
2-2
The ACH 400 with Electronic Bypass is an ACH 400 AC adjustable
frequency drive in an integrated NEMA Type 1 or NEMA Type 12 package
with a bypass motor starter. The ACH 400 with Electronic Bypass provides a
disconnect switch or circuit breaker with door mounted operator (padlockable
in the OFF position), a bypass starter, motor overload protection, a local
operator keypad with indicating lights, and provisions for external control
connections. Side by Side and NEMA Type 12 configurations also provide a
drive service switch as standard.
Figure 2-2 shows the front view of the ACH 400 Electronic Bypass, and
identifies the major components.
Figure 2-2 Electronic Bypass Exterior View
Input power is connected to the ACH 400 with Electronic Bypass through a
door interlocked disconnect switch or circuit breaker.
The door interlocked disconnect switch is not fused. The branch circuit that
provides power to the ACH 400 with Electronic Bypass must include
appropriate motor branch circuit protective devices to provide short circuit
and ground fault protection for the motor in the bypass mode.
The door interlocked circuit breaker is an optional alternative to the door
interlocked disconnect switch. The circuit breaker provides short circuit and
ground fault protection for the motor in the bypass mode.
Drive input fuses are provided to disconnect the drive from power in the event
that a component fails in the drive's power circuitry. Since fast-acting fuses
are provided, the branch circuit protection will not clear when the drive input
fuses blow. If the drive input fuses blow, the motor can be switched to Bypass
without replacing fuses or resetting a circuit breaker. The drive's electronic
protection circuitry is designed to clear drive output short circuits and ground
faults without blowing the drive input fuses. Drive input fuse specifications
are listed in Table 2-1.
ACH 400 with Electronic Bypass User's Manual