ABB MicroFlex e190, Руководство пользователя

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Electrical installation: AC input / DC input, motor and brake 57
Motor brake connection
A rotary motor might require a brake. The brake prevents the uncontrolled release of
suspended or tensioned loads when power to the motor is removed or disconnected,
e.g. by a motor circuit contactor. Contact your local supplier for details of appropriate
brakes.
You can wire a motor's brake, via relays, to a digital output on connector X3; see
Connecting the control cables on page 60 . This provides a way for the
MicroFlex e190 to control the motor's brake. A typical circuit is shown in the following
diagram:
2
+24 V 0 V
12
X3
DO2+
DO2-
User
supply
GND User
supply
V+
Relay
Separate
customer
supplied
24 V DC supply
The relay has normally open
contacts and is shown deactivated
(contacts open, brake engaged).
The inner shield
surrounding the
brake wires should
be earthed/grounded
at one point only.
from motor brake
connections
This circuit uses DO2 as a motor brake output. The output is configured using Mint
keyword
MOTORBRAKEOUTPUT
; see the Mint help file for details. With this
configuration, the following sequences can be used to control the brake.
To engage the brake:
• The motor is brought to rest under normal control;
• The relay is deactivated, causing the brake to engage;
• The drive is disabled, removing power from the motor.
To disengage the brake:
• The drive is enabled;
• The drive applies power to the motor to hold position under normal control;
• The relay is activated, causing the brake to be disengaged.
It is sometimes necessary to include a small delay after the relay has been activated,
before starting motion. This delay allows time for the relay contacts to engage and the
brake to release. See the Mint keyword
MOTORBRAKEDELAY
.
WARNING! The 24 V DC power supply used to power the brake must be a
separate supply as shown in the diagram. Do not use the supply that is
powering the MicroFlex e190 digital outputs. The brake wires often carry noise that
could cause erratic drive operation or damage. The brake contacts must never be
wired directly to the digital outputs. The relay should be fitted with a protective flyback
diode, as shown. The separate 24 V DC supply used for the motor brake can also be
used to power the relay in the thermal switch circuit (see below).