3.10 Braking Resistor
Dynamic braking (DB) helps bring the motor to a smooth and rapid stop when working with
high inertia loads. Regeneration occurs as the drive lowers the motor frequency with high
inertia. When the regeneration flows back into the DC bus capacitors, an overvoltage situation
occurs. A braking resistor prevents these overvoltage faults.
NOTICE: Do not allow unqualified personnel to use the product. Failure to comply could result in damage to
the drive or braking circuit. Carefully review the braking resistor instruction manual when connecting a braking
option to the drive.
Note:
The braking circuit must be sized properly in order to dissipate the power required to decelerate the load
in the desired time. Ensure that the braking circuit can dissipate the energy for the set deceleration time
prior to running the drive.
NOTICE: Use a thermal overload relay or over-temperature contact to interrupt input power to the drive if the
braking resistor overheats. In the event of a possible thermal overload, the relay triggers the input contactor
and prevents the braking resistor from burning up.
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Installation
WARNING! Fire Hazard. The braking resistor connection terminals are B1 and B2. Do not connect a braking
resistor directly to any other terminals. Improper wiring connections could result in death or serious injury by
fire. Failure to comply may result in damage to the braking circuit or drive.
NOTICE: Connect braking resistors to the drive as shown in the I/O wiring examples. Improperly wiring braking
circuits could result in damage to the drive or equipment.
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Installation Procedure
1.
Disconnect all electrical power to the drive and wait at least one minute before
servicing the drive and any connected components.
2.
Remove drive front cover.
3.
Use a voltmeter to verify that voltage is disconnected from incoming power terminals
and that the DC bus no longer holds a charge.
3.10 Braking Resistor
YASKAWA ELECTRIC TOEP C710606 25D YASKAWA AC Drive J1000 Installation & Start-Up Manual
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Electrical Installation