NORD Drivesystems B1000 - Manual (Page 730)

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General
Information
BRAKES
G1000 – Subject to Change Without Notice
Motor-Brake Option (BRE)
The standard NORD motor brake is spring-set when
power is removed from the brake circuit (power-off).
The brake coil utilizes a DC voltage supplied through
a rectifi ed power source.
Advantages
• Each NORD motor frame size has a number of
brake sizes available, with different torque capacities.
• Brake adjustment is possible by changing the brake
spring combinations. In addition, several common
brake sizes also have an additional spanner-nut ad-
justment available.
• Compared to the many AC brakes on the market,
NORD brakes offer better wear capacity, easier fi eld
adjustability, greater reliability, and lower end-cost
to the consumer.
• NORD motor-brakes operate with a high degree
of safety, because the brake is actively engaged with
the no brake supply voltage (power-off).
• The rotating brake disc is environmentally safe
with an asbestos-free friction material bonded to
each side.
• The connection between the rectifi er and the
brake coil is already completed at the factory.
• The brake air-gap is factory-set but can easily be
adjusted in the event of wear.
Operation
The main AC supply power to the brake rectifi er can
be supplied from either the motor terminal board or
from a separately switched power source.
• In typical direct-across-the-line motor operation,
AC brake power may be supplied from the motor’s
terminal board.
• If the motor is a two-speed model, or if the motor
is being controlled by a variable frequency drive or
electrical soft-start, then the brake rectifi er must be
powered from a separate AC source.
When the brake is de-energized (Power off), the
braking springs exert a force against the armature
plate (pressure plate), preventing the brake rotor
from rotating. Conversely, when the brake coil is
energized (Power on), a magnetic fi eld builds and
pulls the armature plate across the air gap to the
brake oil casing. This action frees the brake rotor
and allows the motor shaft to rotate.
Brake Selection
The selection of a motor brake system is broken
down into fi ve phases. The selection of the braking
torque, the selection of the braking times (release
times and setting times), the selection of the elec-
trical supply and connection, the selection of brake
options, and the fi nal phase is the verifi cation of the
permissible brake work.
Selection steps
1) Brake torque (page 730)
2) Brake times (page 734)
3) Electrical supply and connection (page 735)
4) Brake options (page 737)
5) Brake work verifi cation (page 742)