Ametek SEQUOIA Series - AC Input Connections and Wiring

Sequoia / Tahoe Series User Manual California Instruments
42 M447352-01 REV-A
3.5 AC Input Connections and Wiring
Three-phase Delta or Wye AC input voltage of sufficient amperage (consult AC input specifications for
maximum AC current per phase) is required to power the Sequoia/Tahoe Series.
The Power supply front panel POWER switch does not disconnect the AC input line from the unit. Ensure
that an appropriately rated safety device has a rating of 25% over the maximum input line current listed in
the specification of section 2.12 is incorporated in the installation that will provide isolation from the AC
input when the device is opened. The device must be located close to the unit, within the reach of the
operator, and clearly labeled as the disconnection device. This protective device could be a three-phase
circuit breaker or a similar branch circuit protection device with disconnect capability.
3.5.1 AC Input Overcurrent Protection
The Sequoia/Tahoe Series power supply has fuses at the AC input for fault protection. These fuses are
internal to the chassis and are not user accessible. They provide fault isolation in case a failure occurs of
internal components or wiring. A suitable overcurrent protection device must be provided externally, within
the system installation, to protect the external wiring and interconnects.
CAUTION!
AC input connections should be routed through a properly sized and rated three-phase
CIRCUIT PROTECTION device. This will protect building wiring and other circuits from
possible damage or shutdown in case of a system problem. It will also facilitate removing
AC input power to the system in case of service or reconfiguration requirements.
CAUTION!
AC input wiring and connections must conform to local electrical safety codes that apply.
Always consult a qualified electrician prior to installation of any Sequoia/Tahoe System.
The input terminal block is located on the lower end of the rear of the Sequoia/Tahoe chassis. To access
the input terminal block, the protective rear cover needs to be removed first. Refer to Figure 3-3.
CAUTION!
Always disconnect any input power completely when removing any protective cover and
allow the internal capacitors to fully discharge (minimum of 15 mins) before removing any
cover.