Toshiba JK Series Instruction Manual page 13

GENERAL DESCRIPTION
E. Interlocks - Electrical
Control Power Interlock (CPI)
The control power
microswitch (Fig. 9) which is directly driven by
the operation of the switch handle. This normally
open switch is closed only when the handle is
fully ON. As the switch handle is moved from ON
to OFF, the CPI opens before the main contacts
of the power isolation switch. Conversely, during
closing of the switch, the CPI contacts do not
close until after the switch contacts have fully
closed.
The CPI microswitch contacts must be wired in
series with the secondary connected load of the
control power transformer (installed and wired by
the OEM). This ensures that all load is
disconnected from the control power transformer
secondary winding before the isolation switch
can be operated. The isolation switch is
therefore only required to make or break
currents equal to the no-load magnetizing
current of the transformer.
Refer to the INSTALLATION section for the
correct wiring of the control power transformer.
Failure to correctly wire the
CPI contacts in series with
the control transformer
secondary load can result
WARNING
in arcing and failure of the
isolation switch, which can
cause severe injury or
death.
Do not connect additional
load to the isolation switch.
interlock (CPI) is a
Fig. 9 Control Power Interlock
Page 9