Fuji Electric BUC-D Series User manual

Instruction Manual
Stack Type Dynamic Braking Unit
BUC-D Series (690V Type)
Thank you for purchasing our dynamic braking unit (BUC-D Series).
• This product is a device to discharge the braking power to a resistor in a braking operation of the Fuji's inverter for
general industry. Read through this instruction manual to become familiar with proper handling and correct use.
• Improper handling might result in incorrect operation, a short life, or even a failure of this product.
• Deliver this manual to the end user of this product. Keep this manual in a safe place until this product is discarded.
• For the installation and selection of peripheral equipment exclusive to the stack type of inverters, refer to the
FRENIC-VG User's Manual (Stack Type Edition).
• For the configuration of the inverter functions and operating procedure, refer to the FRENIC-VG User's Manual (Unit
Type / Function Codes Edition).
• For details about PWM converters and diode rectifiers, refer to the FRENIC-VG User's Manual (Stack Type Edition).
Fuji Electric Co., Ltd. INR-SI47-1846-E

Copyright © 2014 Fuji Electric Co., Ltd.
All rights reserved.
No part of this publication may be reproduced or copied without prior written permission
from Fuji Electric Co., Ltd.
All products and company names mentioned in this manual are trademarks or registered
trademarks of their respective holders.
The information contained herein is subject to change without prior notice for
improvement.

Preface
Thank you for purchasing our dynamic braking unit (BUC-D Series).This product is a device to discharge the braking power
to a resistor in a braking operation of the Fuji's inverter for general industry.
Read through this instruction manual to become familiar with proper handling for correct use. Improper handling might result
in incorrect operation, a short life, or even a failure of this product as well as the motor.
The related documents are subject to change without notice. Be sure to obtain the latest editions for use.
List of applicable inverters
The table below lists the inverters that can be used in combination with this product.
Inverter series Capacity Inverter type Stack/unit type
VG series All capacities FRNSVG1S-69Stack type
Table of Contents
Preface i
Safety precautions ................................................................................................................................................................. iii
Chapter 1 BEFORE USE ......................................................................................................................................................... 1
1.1 Acceptance Inspection.................................................................................................................................................. 1
1.2 External Appearance..................................................................................................................................................... 2
1.3 Precautions for Using dynamic breaking unit............................................................................................................... 3
1.3.1 Installation environment .......................................................................................................................................3
1.3.2 Storage environment .............................................................................................................................................5
[ 1 ] Temporary storage ................................................................................................................................................5
[ 2 ] Long-term storage.................................................................................................................................................5
Chapter 2 MOUNTING AND WIRING .................................................................................................................................. 6
2.1 Mounting the dynamic breaking unit............................................................................................................................ 6
2.1.1 Terminal Arrangement and Screw Sizes (Main circuit terminals).........................................................................7
[ 1 ] Rank 4 (500 kW)................................................................................................................................................7
2.2 Wiring........................................................................................................................................................................... 8
2.2.1 Connection diagram..............................................................................................................................................8
2.2.2 Removing and mounting the front cover and the wiring guide...........................................................................10
2.2.3 Basic Connections...............................................................................................................................................11
2.2.4 Main circuit terminals.........................................................................................................................................11
[ 1 ] Screw specifications and recommended wire sizes (main circuit terminals) ....................................................11
[ 2 ] Terminal functions (main circuit terminals) .....................................................................................................12
2.2.5 Control circuit terminals .....................................................................................................................................12
[ 1 ] Screw specifications and recommended wire sizes (control circuit terminals)................................................12
[ 2 ] Terminal arrangement (control circuit terminals) .............................................................................................12
[ 3 ] Detailed functions of control circuit terminals .................................................................................................13
[ 4 ] Wiring for the control circuit............................................................................................................................16
2.2.6 Setting up the slide switches ...............................................................................................................................18
2.2.7 Fan power switching connector CN UX .............................................................................................................19
2.2.8 Connecting optical fiber cable ............................................................................................................................20
Chapter 3 TEST RUN PROCEDURE.................................................................................................................................... 21
3.1 Checking Prior to Powering On.................................................................................................................................. 21
3.2 Powering ON and Checking ....................................................................................................................................... 21
Chapter 4 TROUBLESHOOTING ........................................................................................................................................ 21
4.1 Protective Functions ................................................................................................................................................... 21
4.2 Before Proceeding with Troubleshooting ................................................................................................................... 21
4.3 Troubleshooting.......................................................................................................................................................... 22
4.3.1 List of Protective Functions................................................................................................................................22
4.3.2 Possible causes of alarms, checks and measures.................................................................................................22
[ 1 ] Overcurrent ......................................................................................................................................................22
[ 2 ] Overvoltage ......................................................................................................................................................23
[ 3 ] DC Fuse blown.................................................................................................................................................23
[ 4 ] Memory error ...................................................................................................................................................23
i

ii
[ 5 ] CPU error .........................................................................................................................................................23
[ 6 ] Hardware error .................................................................................................................................................24
[ 7 ] Heat sink overheat............................................................................................................................................24
[ 8 ] Dynamic breaking unit internal overheat..........................................................................................................24
[ 9 ] Inter- dynamic breaking unit communications link error .................................................................................24
Chapter 5 MAINTENANCE AND INSPECTION ................................................................................................................ 25
5.1 Inspection Interval ...................................................................................................................................................... 25
5.2 Daily Inspection.......................................................................................................................................................... 25
5.3 Periodic Inspection ..................................................................................................................................................... 26
5.4 List of Periodic Replacement Parts............................................................................................................................. 27
5.5 Insulation Test............................................................................................................................................................. 27
5.6 Inquiries about Product and Guarantee....................................................................................................................... 28
5.6.1 When making an inquiry.....................................................................................................................................28
5.6.2 Product warranty.................................................................................................................................................28
[ 1 ] Free of charge warranty period and warranty range .........................................................................................28
[ 2 ] Exclusion of liability for loss of opportunity, etc. ............................................................................................29
[ 3 ] Repair period after production stop, spare parts supply period (holding period)..............................................29
[ 4 ] Transfer rights ..................................................................................................................................................29
[ 5 ] Service contents................................................................................................................................................29
[ 6 ] Applicable scope of service..............................................................................................................................29
Chapter 6 SPECIFICATIONS................................................................................................................................................ 29

Safety precautions
Read this manual thoroughly before proceeding with installation, connections (wiring), operation, or maintenance and
inspection. Ensure you have sound knowledge of the device and familiarize yourself with all safety information and
precautions before proceeding to operate the inverter.
Safety precautions are classified into the following two categories in this manual.
Failure to heed the information indicated by this symbol may lead to dangerous conditions,
possibly resulting in death or serious bodily injuries.
Failure to heed the information indicated by this symbol may lead to dangerous conditions,
possibly resulting in minor or light bodily injuries and/or substantial property damage.
Failure to heed the information contained under the CAUTION title can also result in serious consequences. These safety
precautions are of utmost importance and must be observed at all times.
Application
• This product is designed to discharge the braking power to a resistor in a braking operation of the Fuji's inverter for
general industry. It cannot be used for others.
Fire or an accident could occur.
• The dynamic braking unit may not be used for a life-support system or other purposes directly related to the human
safety.
• Though the dynamic braking unit is manufactured under strict quality control, install safety devices for applications
where serious accidents or property damages are foreseen in relation to the failure of it.
An accident could occur.
Installation
• Install the dynamic braking unit on a base made of metal or other non-flammable material.
Otherwise, a fire could occur.
• Do not place flammable object nearby.
Doing so could cause fire.
• The dynamic braking unit whose protective structure is IP00 involves a possibility that a human body may touch the
live conductors of the main circuit terminal block. Install the dynamic braking unit in an inaccessible place.
Otherwise, electric shock or injuries could occur.
• Do not support the dynamic braking unit by its front cover during transportation.
Doing so could cause a drop of the inverter and injuries.
• Prevent lint, paper fibers, sawdust, dust, metallic chips, or other foreign materials from getting into the dynamic
braking unit or from accumulating on the heat sink.
• When installing the dynamic braking unit, use screws and bolts specified in the installation procedure and tighten
them with the specified tightening torque.
Otherwise, a fire or an accident might result.
• Do not install or run an dynamic braking unit that is damaged or lacking parts.
Doing so could cause fire, an accident or injuries.
iii

Wiring
• Do not connect the DC terminals (P(+) and N(-)) to the connection terminals on the inverter side in mistake for the
polarity （+ and –）.
• Use wires in the specified size.
• Tighten terminals with specified torque.
Otherwise, a fire could occur.
• Be sure to ground the grounding terminals ( G).
Otherwise, an electric shock or a fire could occur.
• Qualified electricians should carry out wiring.
• Be sure to perform wiring after turning the power OFF.
• Be sure to perform wiring after installing the inverter unit.
Otherwise, an electric shock could occur.
• In general, sheaths of the control signal wires are not specifically designed to withstand a high voltage (i.e.,
reinforced insulation is not applied). Therefore, if a control signal wire comes into direct contact with a live
conductor of the main circuit, the insulation of the sheath might break down, which would expose the signal wire to
a high voltage of the main circuit. Make sure that the control signal wires will not come into contact with live
conductors of the main circuit.
Doing so could cause an accident or an electric shock.
• Before changing the slide switches on the control printed circuit board, turn the power OFF, wait at least ten
minutes, and make sure that the charging lamp are turned OFF. Further, make sure, using a multimeter or a similar
instrument, that the DC link bus voltage between the terminals P(+) and N(-) has dropped to the safe level (+25 VDC
or below).
An electric shock could occur.
• The PWM converter, inverter, motor and wiring generate electric noise. Be careful about malfunction of the nearby
sensors and devices. To prevent them from malfunctioning, implement noise control measures.
Otherwise an accident could occur.
Operation
• Be sure to mount the front cover before turning the power ON. Do not remove the cover when the inverter power is
ON.
Otherwise, an electric shock could occur.
• Do not operate switches with wet hands.
• Do not touch the terminals of the dynamic braking unit in energized state of the inverter even if the inverter has
stopped.
Doing so could cause electric shock.
• Do not touch the heat sink because it becomes very hot.
Doing so could cause burns.
• The braking with this dynamic braking unit cannot function as mechanical holding.
Injuries could occur.
iv

Maintenance and inspection, and parts replacement
• Before changing the slide switches on the control printed circuit board in maintenance or inspection, turn the
power OFF, wait at least ten minutes, and make sure that the charging lamp are turned OFF. Further, make sure,
using a multimeter or a similar instrument, that the DC link bus voltage between the terminals P(+) and N(-) has
dropped to the safe level (+25 VDC or below).
Otherwise, an electric shock could occur.
• Maintenance, inspection, and parts replacement should be made only by qualified persons.
• Take off the watch, rings and other metallic objects before starting work.
• Use insulated tools.
Otherwise, an electric shock or injuries could occur.
• Never modify the inverter.
Doing so could cause an electric shock or injuries.
Disposal
• Treat the dynamic braking unit as an industrial waste when disposing of it.
Otherwise injuries could occur.
General precautions
Drawings in this manual are illustrated without the front cover or safety shields for explanation of detail parts. Do not turn
the power ON when the dynamic braking unit is as shown in drawings. Be sure to restore the covers and shields in the
original state before running the dynamic braking unit.
Icons
The following icons are used throughout this manual.
This icon indicates information which, if not heeded, can result in the dynamic braking unit not operating to full
efficiency, as well as information concerning incorrect operations and settings which can result in accidents.
This icon indicates information that can prove handy when performing certain settings or operations.
This icon indicates a reference to more detailed information.
v

Chapter 1 BEFORE USE
1.1 Acceptance Inspection
Unpack the package and check the following:
(1) A dynamic braking unit and the following accessories are contained.
Accessories - Instruction manual (this document)
(2) The dynamic braking unit has not been damaged during transportation—there should be no dents or parts missing.
(3) The dynamic braking unit is the type you ordered. You can check the type and specifications on the main and sub
nameplates. (The main and sub nameplates are attached to the dynamic braking unit as shown in Figures 1.2-1.)
1
(a) Main Nameplate (b) Sub Nameplate
Figure 1.1-1 Nameplates
BUC500S-69D
- -
1093V DC
594A
- -
- - -
500kW CONT.
135 kg
BUC50
0S
-
69D
TYPE: Type of the dynamic breaking unit
BUC 500 69 DS
Product Type：BUC
Rated output
Structure： S→stack type Voltage class： 69→690V
Series name：BUC-D series
SOURCE : Power ratings
OUTPUT : rated output capacity
MASS : Mass of the dynamic breaking unit in kilogram
SER. No. : Product number
2 8 A 4 5 6 A 0 0 0 1 AA 23 2
Production week
This indicates the week number that is numbered
from the 1st week of January.
The 1st week of January is indicated as "01."
Production year: Last digit of year
Product version
If you suspect the product is not working properly or if you have any questions about your product, contact your Fuji Electric
representative.

1.2 External Appearance
(1) Outside and inside views
Keypad
enclosure
Hoist hole
φ26
Cooling fans
N(-) bar
P(+) barHandle
Warning
plate
Handle
Front cover Hoist holes
φ26
Controle circuit
terminal block
Casters
Sub nameplate
Hoist hole
φ26
Main nameplate
Charge
lamp
Figure 1.2-1 Rank 4 (500 kW)
(2) Warning plates and label
Figure 1.2-2 Warning Plates and Label
2

3
1.3 Precautions for Using dynamic breaking unit
This section provides precautions in introducing dynamic breaking units, e.g. precautions for installation environment, power
supply lines, wiring, and connection to peripheral equipment. Be sure to observe those precautions.
1.3.1 Installation environment
Install the dynamic breaking unit in an environment that satisfies the requirements listed in Table 1.3-1.
Table 1.3-1 Environmental Requirements
Item Specifications
Site location Indoors
Ambient temperature -10 to +40C
Relative humidity 5 to 95% (No condensation)
Atmosphere The dynamic breaking unit must not be exposed to dust, direct sunlight, corrosive gases,
flammable gases, oil mist, vapor or water drops.
Pollution degree 2 (IEC60664-1) (Note 1)
The atmosphere can contain a small amount of salt. (0.01 mg/cm2or less per year)
The dynamic breaking unit must not be subjected to sudden changes in temperature that will
cause condensation to form.
Altitude Less than 1,000 m
If the altitude is 1,000 to 3,000 m, output current derating is required.
If the altitude is 2,001 to 3,000 m, the insulation level of the control circuits lowers from the
reinforced insulation to the basic insulation.
Vibration Compliant to the standard IEC61800-2
Amplitude 0.3 mm: 2 to less than 9 Hz
1 m/s2: 9 to 200 Hz
Compliant to the standard IEC61800-5-1
Amplitude 0.075 mm: 10 to less than 57 Hz
1 G: 57 to 150 Hz
(Note 1) Do not install the dynamic breaking unit in an environment where it may be exposed to lint, cotton waste or moist dust or dirt
which will clog the heat sink of the dynamic breaking unit. If the dynamic breaking unit is to be used in such an environment, install it in a
dustproof cabinet.

4
Fuji Electric strongly recommends installing dynamic breaking units in a cabinet for safety reasons.
When installing the dynamic breaking unit in a place out of the specified environmental requirements, it is necessary to
derate the dynamic breaking unit or consider the cabinet engineering design suitable for the special environment or the
cabinet installation location. For details, refer to the Fuji Electric technical information "Engineering Design of Panels" or
consult your Fuji Electric representative.
The special environments listed below require using the specially designed cabinet or considering the cabinet installation
location.
Environments Possible problems Sample measures Applications
Highly concentrated
sulfidizing gas or
other corrosive gases
Corrosive gases cause parts
inside the dynamic breaking
unit to corrode, resulting in
an inverter malfunction.
Any of the following measures may
be necessary.
- Mount the dynamic breaking unit
in a sealed cabinet with IP6X or
air-purge mechanism.
- Place the cabinet in a room free
from influence of the gases.
Paper manufacturing,
sewage disposal, sludge
treatment, tire
manufacturing, gypsum
manufacturing, metal
processing, and a
particular process in
textile factories.
A lot of conductive
dust or foreign
material (e.g., metal
powders or shavings,
carbon fibers, or
carbon dust)
Entry of conductive dust into
the dynamic breaking unit
causes a short circuit.
Any of the following measures may
be necessary.
- Mount the dynamic breaking unit
in a sealed cabinet.
- Place the cabinet in a room free
from influence of the conductive
dust.
Wiredrawing machines,
metal processing,
extruding machines,
printing presses,
combustors, and industrial
waste treatment.
A lot of fibrous or
paper dust
Fibrous or paper dust
accumulated on the heat sink
lowers the cooing effect.
Entry of dust into the
dynamic breaking unit causes
the electronic circuitry to
malfunction.
Any of the following measures may
be necessary.
- Mount the dynamic breaking unit
in a sealed cabinet that shuts out
dust.
- Ensure a maintenance space for
periodical cleaning of the heat sink
in cabinet engineering design.
- Employ external cooling when
mounting the dynamic breaking
unit in a cabinet for easy
maintenance and perform
periodical maintenance.
Textile manufacturing and
paper manufacturing.
High humidity or
dew condensation
In an environment where a
humidifier is used or where
the air conditioner is not
equipped with a
dehumidifier, high humidity
or dew condensation results,
which causes a
short-circuiting or
malfunction of electronic
circuitry inside the dynamic
breaking unit.
- Put a heating module such as a
space heater in the cabinet.
Outdoor installation.
Film manufacturing line,
pumps and food
processing.
Vibration or shock
exceeding the
specified level
If a large vibration or shock
exceeding the specified level
is applied to the dynamic
breaking unit, for example,
due to a carrier running on
seam joints of rails or
blasting at a construction site,
the inverter structure gets
damaged.
- Put shock-absorbing materials on
the mounting base of the dynamic
breaking unit for safe mounting.
Installation of an dynamic
breaking unit cabinet on a
carrier or self-propelled
machine.
Ventilating fan at a
construction site or a press
machine.
Fumigation for
export packaging
Halogen compounds such as
methyl bromide used in
fumigation corrodes some
parts inside the dynamic
breaking unit.
- When exporting a dynamic
breaking unit built in a cabinet or
equipment, pack them in a
previously fumigated wooden
crate.
- When packing a dynamic breaking
unit alone for export, use a
laminated veneer lumber (LVL).
Exporting.

5
1.3.2 Storage environment
The storage environment in which the dynamic breaking unit should be stored after purchase differs from the installation
environment. Store the dynamic breaking unit in an environment that satisfies the requirements listed below.
[ 1 ] Temporary storage
Table 1.3-2 Storage and Transport Environments
Item Specifications
Storage temperature *1-25 to +70C
Relative humidity 5 to 95% *2
Places not subjected to abrupt temperature changes or
condensation or freezing
Atmosphere The dynamic breaking unit must not be exposed to dust, direct sunlight, corrosive or flammable gases,
oil mist, vapor, water drops or vibration. The atmosphere must contain only a low level of salt. (0.01
mg/cm2 or less per year)
86 to 106 kPa (during storage)Atmospheric pressure
70 to 106 kPa (during transportation)
*1 Assuming comparatively short time storage, e.g., during transportation or the like.
*2 Even if the humidity is within the specified requirements, avoid such places where the dynamic breaking unit will be subjected to sudden
changes in temperature that will cause condensation or freezing.
Precautions for temporary storage
(1) Do not leave the dynamic breaking unit directly on the floor.
(2) If the environment does not satisfy the specified requirements listed in Table 1.3-2, wrap the dynamic breaking unit in an
airtight vinyl sheet or the like for storage.
(3) If the dynamic breaking unit is to be stored in a high-humidity environment, put a drying agent (such as silica gel) in the
airtight package described in (2) above.
[ 2 ] Long-term storage
The long-term storage method of the dynamic breaking unit varies largely according to the environment of the storage site.
General storage methods are described below.
(1) The storage site must satisfy the requirements specified for temporary storage.
However, for storage exceeding three months, the ambient temperature range should be within the range from -10 to
30°C. This is to prevent electrolytic capacitors in the dynamic breaking unit from deterioration.
(2) The package must be airtight to protect the dynamic breaking unit from moisture. Add a drying agent inside the package
to maintain the relative humidity inside the package within 70%.
(3) If the dynamic breaking unit has been installed to the equipment or cabinet at construction sites where it may be
subjected to humidity, dust or dirt, then temporarily remove the dynamic breaking unit and store it in the environment
specified in Table 1.3-2.
Precautions for storage over 1 year
If the dynamic breaking unit has not been powered on for a long time, the property of the electrolytic capacitors may
deteriorate. Power the dynamic breaking unit on once a year and keep the dynamic breaking unit powering on for 30 to 60
minutes.

Chapter 2 MOUNTING AND WIRING
2.1 Mounting the dynamic breaking unit
(1) Installation environment
Mount the dynamic breaking unit at the place satisfying the requirements given in Chapter 1, Section 1.3.1 "Installation
environment."
(2) Mounting base
Install the dynamic breaking unit on a base made of metal or other non-flammable material. Do not mount the dynamic
breaking unit upside down or horizontally.
Install the dynamic breaking unit on a base made of metal or other non-flammable material.
Otherwise, a fire could occur.
(3) Clearances
Mount the dynamic braking unit only in the direction shown in Figure 2.1-1 (in the reading direction of the nameplate). For
the clearances, refer to Figure 2.1-1 and Table 2.1-1. When mounting two or more dynamic braking units side by side,
observe also the clearances specified in Table 2.1-1.
6
E
B
C
D
A
Figure 2.1-1 Mounting Direction and Required Clearances
Table 2.1-1 Clearances (mm)
A B C D E
Rank 4: 500 kW dynamic braking unit size
Between
dynamic
braking units
Rank
4 10 10 300 350 20
With other
equipment 20 50 - 350
(100) 50
- Dynamic braking units cannot be mounted, one above the other.
- Above the dynamic braking unit (i.e. above the exhaust fans) at location "C," only a DC fuse (authorized by Fuji)
can be mounted. To mount general devices, select devices whose maximum allowable working temperature is
70C and prevent them from interfering with the effect of the exhaust fans.
- Beneath the dynamic braking unit (i.e. beneath the intake vent) at location "D," do not block about 60% of the
area in the 350 mm clearance. When mounting a device, ensure a 100 mm clearance.

2.1.1 Terminal Arrangement and Screw Sizes (Main circuit terminals)
[ 1 ] Rank 4 (500 kW)
Internal front view Right side view
(Unit: mm)
For external braking resistor connecting terminal of rank 4,
the cabinet should have relay bar terminals.
Secure terminals with insulators to prevent them from
short-circuiting each other.
Figure 2.1-2 Rank 4 (500 kW)
7

2.2 Wiring
2.2.1 Connection diagram
8
P(+) N(-)
DB1
Ｆdc1
)
Ｎ（－）
Ｐ（＋）
C
R1
T1
R0
T0
DC/DC
_(PLC)
(X2)
(X3)
(X7)
(CM)
(EN1)
(PS)
SINK
SOURCE
(EN2)
Processing
controller
0V+24VDC
30C
30B
30A
<Y2>
<Y3>
<Y4>
<CMY>
SW1
DCF1
DCF2 BUC-D
Dynamic braking unit (Master)
DB2
DB3
External braking resistor
The microswitch for DC fuse
blowout detection
Reset alarm
Changeover signal of
Master/Slave mode
G
Single-phase
690V
Ｆdc2
(Note2)
Cooling Fan ON/OFF
Control
【TX】
【RX】
OPC-VG1-TBSI
Y5A
Y5C
DB1
Ｆdc1
)
Ｎ（－）
Ｐ（＋）
C
R1
T1
R0
T0
DC/DC
_(PLC)
(X2)
(X3)
(X7)
(CM)
(EN1)
(PS)
SINK
SOURCE
(EN2)
Processing
controller
0V+24VDC
30C
30B
30A
<Y2>
<Y3>
<Y4>
<CMY>
SW1
DCF1
DCF2
DB2
DB3
Alarm relay outpu
G
Ｆdc2
Alarm content
【TX】
【RX】
OPC-VG1-TBSI
Y5A
Y5C Ready to run
U
Ｆdc1
Ｎ（－）
Ｐ（＋）
R1
T1
R0
T0
DCF1
DCF2
V
W
G
Ｆdc2
Fan power input
M
Optical cable
(Note3)
(Note4)
(Note5)
(Note6)
(Note2)
(Note3)
(Note4)
(Note5)
(Note6)
(Note9)
(Note9)
(Note1)
Fan power input
Fan power input Auxiliary fan
power input
Auxiliary control
power input
Charge
lamp
Auxiliary fan
power input
Auxiliary control
power input
Charge
lamp
Voltage
detector
Voltage
detector
Current
detector
Current
detector
External braking resistor
Reset alarm
Changeover signal of
Master/Slave mode
Cooling Fan ON/OFF
Control
Alarm relay outpu
Alarm content
Ready to run
BUC-D
Dynamic braking unit (Slave)
VG1
Inverter stack
The microswitch for DC fuse
blowout detection
The microswitch for DC fuse
blowout detection
(Note10)
(Note10)
(Note11)
(Note11)

(Note 1) Using a PWM converter for the connection, insert an insulation transformer or auxiliary B contact (normally-closed) of a
power side magnetic contactor.
(Note 2) To retain an alarm output signal even if the main power has shut down, connect these terminals to the power supply lines.
Without power supply to these terminals, the dynamic breaking unit can run.
(Note 3) Do not remove the short circuit conductor.
(Note 4) Slide switches on the control printed circuit board (control PCB).
(Note 5) For wiring enclosed with , use twisted or shielded wires. In principle, the shielded sheath of wires should be
connected to ground.
If the dynamic breaking unit is significantly affected by external induction noise, however, connection to [CM] may be
effective to suppress the influence of noise.
Keep the control circuit wiring away from the main circuit wiring as far as possible (recommended: 10 cm or more).
Never install them in the same wire duct. When crossing the control circuit wiring with the main circuit wiring, set them at
right angles.
(Note 6) If you use Master mode, then connect to [X7] – [CM]. If you use Slave mode , don’t connect.
(Note 7) Because of the need to connect and use the braking unit of two, this product requires a high-speed serial communications
(OPC-VG1-TBSI). An optical cable ( 5m ) is enclosed by standard attachment to the terminal block.
(Note 8) The failure signal of the dynamic braking unit is outputted. Set it as external alarm [THR] any of [X1] ‐[X9] terminal
of an inverter, and connect.
(Note 9) The wiring length of PN bus-bar between the master of dynamic braking unit and the slave and, between the dynamic
braking unit and the inverter should give as 5 m or less.
(Note 10) The charge lamp lights just to the energization of the auxiliary control power input.
(Note 11) The external braking resistor connects with DB1, DB2, and DB3 between DC link bus N bars.
9

Follow the procedure below. (In the following description, the dynamic breaking unit has already been installed.)
2.2.2 Removing and mounting the front cover and the wiring guide
(1) To remove the front cover, loosen the screws (ten) on the front cover.
The front cover fixing points have double circle holes that allow the front cover to be removed without removing the
screws.
(2) Hold the handles and slide the cover up and towards you.
(3) Mount the front cover in the reverse order of removal.
(4) To show the control circuit terminals on the control printed circuit board, open the keypad enclosure (left-hand door).
Keypad enclosure
Screws
Front cover
Screws
Figure 2.2-1 Removing the Front Cover
10

2.2.3 Basic Connections
(1) The grounding terminal must be grounded to prevent disasters such as electric shock and fire and reduce the noise.
(2) Use a reliable crimp terminal to connect each lead.
(3) After making connections (wiring), check that:
1) leads are correctly connected,
2) all necessary connections are made, and
3) no terminal or wire is short-circuited or grounded.
(4) When any connection is changed after the dynamic breaking unit is energized:
It takes a long time for the smoothing capacitor in the DC link circuit of the main circuit to be discharged after the power
supply is shut off. After the CHARGE lamp goes off, check with a multimeter or such that the DC voltage has been
reduced to a safe level (25V DC or less). Short-circuiting a circuit in which a voltage (potential) still remains may
generate sparks. Wait until the voltage goes away.
• Be sure to use wires in the specified size.
• Tighten terminals with specified torque.
Otherwise, a fire could occur..
• Be sure to ground the grounding terminals G.
Otherwise, an electric shock or fire could occur.
• Qualified electricians should carry out wiring.
• Be sure to perform wiring after shutting down the power.
Otherwise, electric shock could occur.
• Be sure to perform wiring after installing the dynamic breaking unit.
Otherwise, electric shock or injuries could occur.
2.2.4 Main circuit terminals
[ 1 ] Screw specifications and recommended wire sizes (main circuit terminals)
This section provides information on choices of wire sizes for main circuit.
Depending upon the main circuit wiring, electric noise could be applied to the control circuit, causing malfunctions.
Refer to the FRENIC-VG User's Manual (Stack type), Chapter 7 "EMC Compatible Peripherals," Appendix 5 "Proficient
Way to User Inverters (on Electric Noise), and Appendix 6 "Grounding As Noise Countermeasure and Ground Noise."
(1) Screw specifications Table 2.2-1 Screw Specifications
Inverter P(+)-N(-) line
connecting terminal
[P(+), N(-)]
External braking
resistor connecting
terminal
[DB1, DB2, DB3]
Type Grounding terminals
[G]
Auxiliary control
power input terminals
[R0, T0]
Auxiliary fan
power input terminals
[R1, T1]
Input terminals for fuse
blowout detection
[DCF1, DCF2]
BUCS-69D Screw
size
Tightening
torque
(N·m)
Screw
size
Tightening
torque
(N·m)
Screw
size
Tightening
torque
(N·m)
Screw
size
Tightening
torque
(N·m)
Screw
size
Tightening
torque
(N·m)
500 M12 48 M12 48 M12 48 M4 1.8 M3 0.5
(2) Recommended wire sizes
Table 2.2-2 Recommended Wire Sizes (Ambient temperature: 40°C)
11
Type
Inverter P(+)-N(-) line
connecting terminal
[P(+), N(-)] (mm2)
BUCS-69D When bus bar
is used When wire is used
External braking
resistor connecting
terminal
[DB1, DB2, DB3]
(mm2)
Grounding terminal
[G]
(mm2)
Auxiliary control
power input terminals
[R0, T0]
Auxiliary fan
power input terminals
[R1, T1]
(mm2)
Input terminal for fuse
blowout detection
[DCF1, DCF2]
(mm2)
t4x50500 100 38 38 2 1.25
(Note) The recommended wire sizes listed above are for 1500 V MLFC insulated wires.

[ 2 ] Terminal functions (main circuit terminals)
Classifi-
cation
Symbol Name Functions
DB1, DB2, DB3 External braking
resistor connecting
terminal
Three sets of external braking resistor are used, and it connects with DB1, DB2, and
DB3 between DC link bus N bars.
P(+), N(-) Inverter P(+)-N(-)
line connecting
terminal
Connects the P(+)-N(-) line of inverter.
R0, T0 Auxiliary power
inputs for control
circuit
Connect the same AC power lines as the main power input for a backup of the control
circuit power supply.
When the inverter is used in combination with the PWM converter, insert an insulation
transformer or auxiliary B contact (normally-closed) of a power side magnetic
contactor.
R1, T1 Auxiliary power
inputs for fans
Power terminals for AC cooling fans. Connect an AC power supply to these terminals.
To match the power specifications, set the fan power switching connectors U1 and U2.
For details, refer to Section 2.2.7.
DCF1, DCF2 Inputs for fuse
blowout detection
Terminals for detecting a blowout of the DC fuse.
When the circuit between terminals [DCF1] and [DCF2] is OFF, the dynamic breaking
unit can detect the blowout of the DC fuse.
To use the detection function, remove the short bar from these terminals to close the
microswitch of the DC fuse. (24 VDC 12 mA typ.)
Main circuit
G Grounding for
dynamic breaking
unit
Grounding terminals of the dynamic breaking unit.
2.2.5 Control circuit terminals
[ 1 ] Screw specifications and recommended wire sizes (control circuit terminals)
Table 2.2-3 lists the screw specifications and recommended wire size for wiring of the control circuit terminals.
Table 2.2-3 Screw Specifications and Recommended Wire Size
Screw specifications
Recommended wire size (mm2)
Screw size Tightening torque (N·m)
Control circuit terminals M3 0.7 1.25 *
[ 2 ] Terminal arrangement (control circuit terminals)
Not available terminal. Don’t connect any wire.
Do not remove the short bar of [EN1], [EN2] and [PS] terminal.
12