Preliminary Recommendations - Schneider Altivar 61/71 Guía De Explotación

Preliminary recommendations

Receipt
Ensure that the equipment reference marked on the label conforms to the delivery note corresponding to the purchase order.
Open the packaging and check that the equipment has not been damaged in transit.
For successful setup, it is important to check that the braking unit, protection devices and mounting are correct. For more information, please
contact your local representative.
Capacitor discharge!
Before any operation on or in the braking unit, disconnect the power line supply and wait 15 minutes for the DC bus to discharge completely.
Measure the voltage on the DC bus before any intervention. This should be less than 60 V DC.
Automatic restart!
In certain cases, depending on its parameter setting, the drive may restart automatically when the power is restored. The safety of nearby
equipment and people must be assured.
General
As a motor slows down on a deceleration ramp, it is working as a generator. A standard drive uses a rectifier that cannot return electrical
energy to the distribution network.
During operation as a generator, the voltage at the DC bus terminals increases due to the regeneration of energy from the motor to the
drive. This locks out the drive on a DC bus overvoltage fault.
The regenerated power in the drive depends on the inertia of the load to be braked and the required braking time.
The drive protects itself against locking out due to DC bus overvoltage by auto-adapting its deceleration ramp. If a shorter deceleration time
is required, a BRAKING UNIT must be used.
The braking unit is an external module that is controlled by the drive. If the voltage at the DC bus terminals exceeds a preset value, an
external resistor is connected in the DC circuit to dissipate the energy.
The minimum resistance should be chosen in relation to the braking unit characteristics tables, and its power rating depends on the
application.
It is advisable to use a line contactor in the drive power supply sequence. This contactor must open when a fault occurs.
RISK OF EQUIPMENT DAMAGE
• Do not short-circuit the DC bus or PA - PB terminals.
• The braking resistors should be installed in a non-flammable atmosphere with no humidity.
• Ensure that the braking unit is connected with the correct polarity.
Failure to follow these instructions can result in injury and/or equipment damage.
1757084 11/2009
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CAUTION
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Braking
resistor
Braking unit
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