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2.17 Braking Resistor Installation
116
YASKAWA
SIEPC71061723A YASKAWA AC Drive CR700 Technical Manual
2.17 Braking Resistor Installation
A braking resistor or braking resistor unit (dynamic braking option) helps stop the motor quickly and smoothly
when there is high load inertia. If you try to decelerate a motor in less time than usual for a coast to stop, the
motor will rotate faster than the synchronous speed that aligns with the set frequency. This will cause the motor to
become an induction generator. The inertia energy of the motor and regenerate to the drive and charge the drive
DC bus capacitor and increase the voltage. If the voltage is more than the overvoltage level, an
ov [Overvoltage]
will occur. To prevent these overvoltage faults, a dynamic braking option is necessary.
WARNING!
Set L3-04 = 0 [Stall Prevention during Decel = Disabled] when you operate the drive with:
• a regenerative converter
• regenerative unit
• braking unit
• braking resistor
• braking resistor unit.
If you set the parameter incorrectly, the drive can decelerate for too long and cause serious injury or death.
NOTICE:
Damage to Equipment. Before you connect a dynamic braking option to the drive, make sure that qualified personnel
read and obey the Braking Unit and Braking Resistor Unit Installation Manual (TOBPC72060001). If you do not read and obey
the manual or if personnel are not qualified, it can cause damage to the drive and braking circuit.
Note:
•
Select the correct braking circuit size to dissipate the power that is necessary to decelerate the load in the correct time. Before you run
the drive, make sure that the braking circuit can dissipate the energy for the set deceleration time.
•
To install a dynamic braking option, set
L8-01 = 0 [3% ERF DB Resistor Protection = Disabled]
.
WARNING!
Fire Hazard. Do not connect a braking resistor to ter1 or -. Use terminals B1 and B2 for the braking resistor
connections. If you connect a braking resistor to the incorrect terminals, it can cause damage to the drive and braking circuit and
serious injury or death.
NOTICE:
Connect braking resistors to the drive as shown in the connection diagram examples. If you wire the braking circuits
incorrectly, it can cause damage to the drive or equipment.
To connect a Yaskawa ERF series braking resistor to the drive, set
L8-01 = 1 [Enabled]
.
To use a non-ERF type braking resistor, connect a thermal overload relay between the drive and the braking
resistor, and set a circuit to de-energize the drive at the trip contacts of the thermal overload relay.
◆
Installing a Braking Resistor: ERF Type
Connect the braking resistor as shown in the following figure for drive models 2003 to 2018 and 4002 to 4009.
Set
L8-01 = 1 [3% ERF DB Resistor Protection = Enabled]
and set any parameter from
H2-01 to H2-05 [MFDO
Function Selection]
to
D [Braking Resistor Fault]
. Use a sequence that shuts the power OFF by using MFDO.
Figure 2.125 Installing a Braking Resistor: ERF Type
◆
Installing a Braking Resistor Unit : LKEB Type
Connect the braking resistor unit as shown in the following figure. To install a braking resistor unit, set
L8-01 = 0
[3% ERF DB Resistor Protection = Disabled]
.
Models 2003 to 2115 and 4002 to 4150 have a built-in braking transistor.
To protect the braking resistor unit from overheating, set up a sequence that shuts off the supply of power at the
trip contacts of the thermal overload relay.
Summary of Contents for CR700
Page 1: ......
Page 244: ...3 13 Test Run Checklist 244 YASKAWA SIEPC71061723A YASKAWA AC Drive CR700 Technical Manual ...
Page 422: ...7 7 Storage Guidelines 422 YASKAWA SIEPC71061723A YASKAWA AC Drive CR700 Technical Manual ...
Page 426: ...8 2 Disposal Instructions 426 YASKAWA SIEPC71061723A YASKAWA AC Drive CR700 Technical Manual ...
Page 837: ...EZZ023535 2 35 1 Revision History Revision Revised Content Date First Edition 2017 08 ...
Page 872: ...EZZ023536 2 16 Revision History Revision Revised Content Date First Edition 2017 08 ...