Maeda MC285C-3 - Main Breaker Switch

Section 4 – ELECTRIC MOTOR COMPONENTS Mini-Crawler Crane M A E D A
4-114 1/2019 MC285C-3
Main Breaker Switch
WARNING!
• Fire Hazard. Do not turn the main breaker to
the ON position until all inspection,
maintenance and repair to the electric
system is completed.
• If the main breaker is automatically turned
off during operation or failure occurs,
immediately stop all operations and correct
failures before resuming operation. Inspect
the inverter unit, electric motor and electric
wiring for failure and burned parts.
Immediately contact us or our sales service
agency to request inspection and repair
service.
• Inspections and repairs must be completed
before turning ON the breaker to re-supply
power.
Potential fire or machine failure may occur if
disregarded.
The main breaker is equipped with the parts
shown in the figure below.
Fig. 4-299
1 - Breaker
2 - Overvoltage/ground-fault indication button
(yellow)
3 - Trip button (red)
4 - Ground-fault test button (gray)
• The breaker (1) is designed to provide automatic
shutoff of the power that is supplied from the
Inverter unit to the electric motor, in the event of
an error including overvoltage, to prevent fire
and machine failure.
The breaker (1) also controls the supply of power
to the electric motor and Inverter unit.
• ON: Power is supplied.
• OFF: No power is supplied.
• The overvoltage/ground-fault indication button
(2) on the cover is designed to eject in the event
of an overvoltage or ground fault.
To reset, press the breaker to turn ON.
• The trip button (3) is designed to mechanically
trip the breaker as an external control.
• The ground-fault test button (4) is used to test
tripping in response to a ground fault.
Proper tripping is assured if the
overvoltage/ground-fault indication button (2) on
the cover ejects.
CAUTION: Periodic (biannual) ground fault
test is recommended.
The test button should be controlled at
10-second or longer intervals and not be
pressed more than required.
If an indication of a ground fault remains on
after the overvoltage/ground-fault indication
button (2) is reset, contact us or our sales
service agency to request inspection or
repair.