Installing Peripheral Devices; Installing Peripheral Devices; Dynamic Braking Options - YASKAWA AC Drive-A1000 Technical Manual

8.5 Installing Peripheral Devices

8.5

Installing Peripheral Devices

This section describes the proper steps and precautions to take when installing or connecting various peripheral devices to the
drive.
NOTICE: Use a class 2 power supply (UL standard) when connecting to the control terminals. Improper application of peripheral devices
could result in drive performance degradation due to improper power supply.
u

Dynamic Braking Options

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 moving a high inertia load, 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 resistor option to the drive.
Note: 1. Properly size the braking circuit 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.
2. Set L8-55 to 0 to disable the internal braking transistor of the drive protection when using braking resistor options.
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 Installing a Braking Resistor: ERF type
An ERF type braking resistors provides dynamic braking capability with up to 3% ED. It can be directly connected to the
drives B1 and B2 terminals like shown in
Enable the drive's braking resistor overload protection by setting L8-01 = 1 when using ERF type resistors.
n Installing a Braking Resistor Unit: LKEB type
LKEB type braking resistors provide dynamic braking capability with up to 10% ED. They can be directly connected to the
drives B1 and B2 terminals as shown in
order to switch off the drive in case braking resistor overheat occurs.
As the drives internal braking resistor overload protection cannot protect LKEB resistors, disable this function by setting L8-01
to 0 and L8-55 to 0.
366
Figure 8.5.
B1
Drive
B2
Figure 8.5 Connecting a Braking Resistor: ERF Type
Figure 8.6. The LKEB unit has a thermal overload contact that should be utilized in
B1
Drive
B2
Figure 8.6 Connecting a Braking Resistor Unit: LKEB Type
(CIMR-Ao5A0003 to 0032)
YASKAWA ELECTRIC SIEP C710616 31B YASKAWA AC Drive – A1000 Technical Manual
Braking Resistor
Braking Resistor Unit
(LKEB type)
P 1
Thermal Relay
Trip Contact
B 2