General Description; Construction - Toshiba JK 400 Series Instruction Manual

Basic Installation and Operation Guide

GENERAL DESCRIPTION

Toshiba JK 400 ampere medium voltage controllers are AC
general-purpose NEMA Class E2 controllers designed for
applications at utilization voltages ranging from 2.3 through 6.6
kV. They are normally used to control motor loads, although
other types of loads such as variable frequency drives (VFDs),
transformers and capacitors are possible.

Construction

The standard enclosure size for the 400 ampere controller is
30" wide by 36" deep by 46", 60" or 90" high. In a typical one-
high arrangement, each section is divided into two isolated
compartments, each with a separate door. The lower
compartment contains medium voltage controller components
(>600V) while the upper compartment contains low voltage
components (<600V) (Fig. 22). In a two-high arrangement,
each enclosure is divided vertically into three major compart-
ments, each with a separate door. The uppermost and lower-
most compartments contain medium voltage controller components while the middle compartment contains low
voltage components. Other variations of this basic arrangement are possible.
Main horizontal bus is provided when required to supply power to a line-up of controllers. The main bus is located at
the rear of the enclosure midway between the top and bottom. A common ground bus is also provided for multiple
sections.
The medium voltage compartment (Fig. 23) consists of:
1) Fix-mounted non-load break isolation switch
2) Fix-mounted vacuum contactor
3) Fix-mounted current-limiting power fuses
4) Current transformers for metering
5) Control power transformer and optional potential transformer
6) Load cable terminations
TOSHIBA
JK 400 Series Fixed Controllers
BLANK OR
ADDITIONAL
ISOLATION POWER
SWITCH
MV
O
N
STARTER
O
F
F COMPONENTS
LOW LOW
VOLTAGE VOLTAGE
POWER
ISOLATION
O
STARTER N STARTER
SWITCH
O
F
F
Fig. 22 Typical Controller Arrangements
Fig. 23 Controller Compartment
LOW
VOLTAGE
POWER POWER
ISOLATION
O STARTER O ISOLATION
N N
SWITCH SWITCH
O O
F F
F F
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