3.10 Braking Resistor 3.10 Braking Resistor Dynamic braking (DB) helps bring the motor to a smooth and rapid stop when working with high inertia loads. As the drive lowers the frequency of a motor with high inertia connected, regeneration occurs. This can cause an overvoltage situation when the regenerative energy flows back into the DC bus capacitors. 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 an over-temperature contact to interrupt input power to the drive in the event the braking resistor overheats. In the event of a possible thermal overload, the relay will trigger the input contactor and prevent the braking resistor from burning up. u 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. n 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.
Electrical Installation Fault contact Figure 3.20 Connecting a Braking Resistor 4. Follow manufacturer instructions to connect the resistor unit to the drive using proper wire gauge according to local electrical codes. 3 Power leads for the remote mount resistors generate high levels of electrical noise; group these signal leads separately. 5. Mount the resistor unit on a noncombustible surface. Maintain minimum side and top clearances according to resistor manufacturer instructions. WARNING! Fire Hazard. Do not use improper combustible materials. Failure to comply could result in death or serious injury by fire.
Attach the drive or braking resistors to metal or other noncombustible material. 6. Reinstall drive covers and resistor covers, if provided. 7. Set parameter L3-04 = “0” to disable stall prevention during deceleration. Set parameter L8-01 to “1” to enable overheat protection when using a heatsink-mounted braking resistor option. Set L8-01 = “0” for other braking resistor types. Table 3.14 Braking Resistor Settings 8. Operate the system and verify the required deceleration rate is obtained during dynamic braking or stopping.
SIEP C710606 33A OYMC AC Drive – J1000 User Manual 47 Thermal relay Braking resistor Power supply MCCB MC R/L1 B1 B2 S/L2 U/T1 T/L3 V/T2 Motor W/T3 THRXOFFON MC Drive SA MC THRX SA Thermal relay switch for external braking resistor MC TRX SA TRX MA MC THRXOFFON MC T Thermal relay switch external braking resis MC MA MC MC SA HRX SA for tor TRX SA TRX Parameter Settings L8-01: Internal Dynamic Braking Resistor Protection Selection 0: Disabled. The drive will not provide overheat protection. Supply separate means of overheat protection. 1: Enabled. Braking Resistor is protected from overheat. L3-04: Stall Prevention During Deceleration 0: Stall prevention disabled.