Yaskawa GPD503 User Manual
Dynamic braking (db) option, Braking unit(s) and braking resistor unit(s))
DWG. NO. 02Y00025-0393
SHEET NO. 1 OF 10
R E L . 4 / 2 6 / 9 6
FOR:
230V
460V
GPD 503
1 5 - 1 0 0 H P
2 5 - 5 0 0 H P
GPD 515
1 5 - 1 0 0 H P
3 0 - 5 0 0 H P
VCD 703
1 5 - 5 0 H P
2 5 - 4 0 0 H P
CHANGE RECORD
1 STD-6654 7/12/96
4 MarCom Chg 9/11/98
2 STD-7093 3/4/97
5 MarCom Chg 12/22/98
3 STD-7483 12/3/97
DYNAMIC BRAKING (DB) OPTION
(Braking Unit(s) and Braking resistor Unit(s))
(Part Numbers Determined by Drive Rating)
Before installing this option, a TECHNICALLY
QUALIFIED INDIVIDUAL who is familiar with this
type of equipment and the hazards involved, should
READ this ENTIRE INSTRUCTION SHEET.
IMPORTANT
This option may have been installed by the factory.
However, certain steps can only be completed at the
installation site. Therefore, review and perform those
steps which complete the installation process.
UL/cUL Compliance
For this Dynamic Braking (DB) unit to comply with
UL/cUL regulations, a fuse must be used in
conjunction with it. The fuse specified must be a
semiconductor device, which must be wired in series
with the DC negative bus, between the drive and the
DB unit, as shown in Figures 2 and 3. The fuse and
fuse holder information is as follows;
Drive Input
Yaskawa
Part number
Voltage
Fuse
Fuse Holder
230v/460v
05P00017-0525
05P00019-0149
600v
05P00017-0526
05P00019-0150
For applications requiring multiple DB Units, multiple
fuses and holders; See Figure 3.
RECEIVING
All equipment is tested against defect at the factory.
Report any damages or shortages evident when
equipment is received immediately to the commercial
carrier who transported the equipment. Assistance, if
required, is available from your
Yaskawa
sales
representative.
DESCRIPTION
Installation of this option enables the motor to be
brought to a smooth and rapid stop. This is achieved
by dissipating the regenerative energy of the AC
motor across the resistive components of the
Dynamic Braking option.
Dynamic Braking Operation
Whenever an excited motor is operated in the
negative slip region (or is subjected to an overhauling
load), the motor will behave as an induction
generator. In this mode, energy will actually flow from
the motor back into the drive.
This energy will cause the DC Bus voltage to rise.
Another condition that will cause the DC Bus voltage
to rise is when the input voltage to the drive is high.
When the DC Bus voltage reaches a certain level, the
Dynamic Braking option will activate. The option will
actually “shunt” the regenerative energy away from
the bus capacitors, and will dissipate it as heat in the
DB resistors. Since the regenerative energy is
dissipated in the resistors, the Overvoltage (OV) trip is
prevented; thus the motor remains excited and
continues to produce braking torque. However, for the
high input voltage condition, an input contactor (1M)
should be used (see Figure 1 or 2) to disconnect the
drive when the high input voltage exists for a long
period of time.
STORAGE
If the option is not to be installed immediately, it must
be stored under the following conditions:
– Ambient temperature: -10 to +40° C.
– Protected from rain and moisture.
– Free from corrosive gases or liquids.
– Free from dust or metal particles.
– Clean and dry.
– Free from excessive vibration.