Inovance MDBUN Series User manual

Inovance MDBUN Series Braking Unit User Manual
Page 1 of 24
Preface
Thank you for purchasing Inovance MDBUN series braking unit.
Inovance MDBUN series braking unit applies to the applications where an AC drive or
servo drive (hereinafter referred to as "drive") needs to perform deceleration, positioning
or braking operation. When the drive performs braking, kinetic energy is converted to
electric energy which is fed back to the drive due to the mechanical inertia of the load.
This will cause rising of the DC bus voltage of the drive. Therefore, a braking unit is
required to ensure normal running of the drive. The regenerative energy is consumed by
the braking resistor, preventing the drive from stopping or even being damaged due to
overvoltage protection.
Inovance MDBUN series braking unit provides full protection functions, such as
overcurrent, overheat, and braking unit open-circuit and short-circuit protection. It
supports the setting of parameters including braking start/stop voltage, and braking rate.
Multiple braking units can be deployed in master/slave mode to meet the braking
requirements of high power drive.
Inovance MDBUN braking unit also applies to large-inertia applications that require
sudden stop, for example, such as elevators, textile machines, paper making machines,
centrifuges, wire drawing machines, winding machines, proportional linkage systems, and
crown blocks.
Before performing installation, wiring, operation, maintenance, and inspection, read and
understand this manual thoroughly and follow the instructions. Failure to observe the
instructions may result in personal injury or even death.
Note
The drawings in this manual are sometimes shown without cover or protective guard.
Remember to install the cover or protective guard as specified first, and then perform
operations in accordance with the instructions.
The drawings in this manual are shown for description only and may not match the
product that you have purchased.
The instructions are subject to change due to product upgrade, specification
modification, as well as the efforts to increase the accuracy and convenience of the
manual
Contact the regional agent or customer service center of Inovance if the manual
delivered is lost or damaged.
Contact the customer service center of Inovance if you have problems during the use.

Inovance MDBUN Series Braking Unit User Manual
Chapter 1 Safety Information
In this manual, the notices are graded based on the degree of danger:

DANGER
indicates that failure to comply with the notice will result in severe
personal injury or even death.

WARNING
indicates that failure to comply with the notice will result in personal
injury or property damage.
Read this chapter carefully so that you have a thorough understanding. Installation,
commissioning or maintenance must be performed in conjunction with this chapter.
Inovance will assume no liability or responsibility for any injury or loss caused by improper
operation.
Use Stage
Safety
Grade
Precautions
Before
installation
DANGER
Do not install the device if you find water seepage, component
missing or damage upon unpacking.
Do not install the device if the packing list does not conform to the
product you received.
WARNING
Handle the device with care during transportation to prevent damage
to the device.
Do not use the device if any component is damaged or missing.
Failure to comply will result in personal injury.
Do not touch the components with your hands. Failure to comply will
result in static electricity damage.
During
installation
DANGER
Install the device on incombustible objects such as metal, and keep it
away from combustible materials. Failure to comply may result in a
fire.
Do not loosen the fixed screws of the components, especially the
screws with red mark.
WARNING
Do not drop wire end or screw into the braking unit. Failure to comply
will result in damage to the braking unit.
Install the braking unit in places free of vibration and direct sunlight.
When two braking units are laid in the same cabinet, arrange the
installation positions properly to ensure the cooling effect.
Keep the braking unit close to the drive and ensure that the cable
between them is twisted and does not exceed 5 m.
At wiring
DANGER
Wiring must be performed only by qualified personnel under
instructions described in this manual. Failure to comply may result in
unexpected accidents.
Ensure that the power supply is cut off before wiring. Failure to
comply may result in electric shock.
Ground the device properly. Failure to comply may result in electric
shock.

Inovance MDBUN Series Braking Unit User Manual
Page 3 of 24
WARNING
Connect the (+) and (-) terminals of the DC bus correctly.
Otherwise, the device may be damaged. Pay attention to the
terminal marks.
Ensure that wiring meets the EMC requirements and local safety
standard. Use wire sizes recommended in the manual. Failure to
comply may result in accidents.
Never connect the braking resistor between the DC bus terminals (+)
and (-). Failure to comply may result in a fire.
Before
power-on
WARNING
Check that the voltage class of the power supply is consistent with
the rated voltage class of the braking unit, and that the wiring
between the braking unit and the braking resistor is secure.
Otherwise, the braking unit may be abnormal or damaged.
Do not perform the voltage resistance test on any part of the braking
unit because such test has been done in the factory. Failure to
comply will result in accidents.
DANGER
Cover the braking unit properly before power-on to prevent electric
shock.
All peripheral devices must be connected properly under the
instructions described in this manual. Failure to comply will result in
accidents
After
power-on
DANGER
Do not open the cover of the braking unit cover after power-on.
Failure to comply may result in electric shock.
The braking unit automatically performs safety check on the
external strong-current circuit after power-on. Do not touch the +, -,
P(+), and BR terminals. Failure to comply may result in electric
shock.
Do not touch the externally connected braking resistor. Failure to
comply may result in electric shock.
During
operation
DANGER
Do not touch the fan or the braking resistor to check the temperature.
Failure to comply will result in personal burnt.
Signal detection must be performed only by qualified personnel
during operation. Failure to comply will result in personal injury or
damage to the braking unit.
During
maintenance
DANGER
Repair or maintenance of the braking unit may be performed only by
qualified personnel. Failure to comply will result in personal injury or
damage to the braking unit.
Do not repair or maintain the braking unit at power-on. Failure to
comply will result in electric shock.
Repair or maintain the braking unit only after ensuring that the input
bus voltage is lower than 36 VDC, 5 minutes after power off.
Otherwise, residual charge on the capacitor may result in personal
injury.
Set and check the parameters again after the braking unit is
replaced.
All the pluggable components must be plugged or removed only after
power-off.

Inovance MDBUN Series Braking Unit User Manual
Chapter 2 Product Information
2.1 Product Appearance and Designation Rules
Figure 2-1 Nameplate and designation rules of the MDBUN
MODEL: MDBUN-90-T
INPUT: DC 300 - 800V
OUTPUT: 0 - 90A
Suzhou Inovance Technology Co.,Ltd.
S/N: 010131264C800109
POWER: 63kW
Model
Rated power
Rated input
Rated output
S/N
Nameplate
Voltage Class
S220 VAC
Rated braking current
MDBUN 90 T
T380 VAC
5T 480 VAC
Series name
Position of
nameplate
2.2 Model and Technical Specifications
Table 2-1 Model and technical specifications of MDBUN series braking unit
Braking Unit
Model
Input Voltage
of Adaptable
Drive
Rated
Continuous
Braking Current
(A)
Peak
Braking
Current
(A)
Max.
Continuous
Braking Power
(kW)
Min. Braking
Resistance (Ω)
MDBUN-45-S
220 VAC
45
54
21
8
MDBUN-60-S
60
72
27
6
MDBUN-90-S
90
108
41
4
MDBUN-45-T
380 VAC
45
54
38
15
MDBUN-60-T
60
72
51
11
MDBUN-90-T
90
108
76
8
MDBUN-45-5
T
480 VAC
45
54
43
17
MDBUN-60-5
T
60
72
58
13
MDBUN-90-5
T
90
108
86
9

Inovance MDBUN Series Braking Unit User Manual
Page 5 of 24
2.3 Working Principle of the MDBUN
Figure 2-2 Application principle of the MDBUN braking unit
Status
indication Braking
control board
Operation
panel
interface
DI1
DO1
DO2
DC
+
P(+)
BR
External
braking
resistor
Block diagram of
the braking unit
Connect the common bus
terminal + of the drive
Connect the common bus
terminal –of the drive
DC Voltage
detection
Auxiliary
power supply
Braking
IGBT
–
The braking unit consumes the electric energy fed back from the motor to the drive to limit
the voltage of the drive within a secure range.
Before normal running of the braking unit, you need to set the braking start and stop
voltages based on theAC power voltage class of the drive. The following figure shows the
braking start and stop voltages and voltage during normal running of the main capacitor.
Figure 2-3 Working principle of the MDBUN braking unit
Acceleration or
stable-speed
running Braking running at
deceleration Stop Start Braking running at deceleration Stop
(P0-00)
(P0-01)
(P0-02)
Bus voltage (V)
Braking start
voltage
Braking stop
voltage
Normal bus voltage
Braking
IGBT state
Braking unit
DO output
Time (s)
As shown in the preceding figure, the relationship between three voltages is as follows:
Braking start voltage > Braking stop voltage> Normal bus voltage. When the braking unit
is in the master mode, the control circuit detects the bus voltage in real time. If the bus
voltage reaches the set braking start voltage (set in P0-00), the braking IGBT starts to
work and discharges the electricity in the main capacitor of the drive through the external
braking resistor, so that the bus voltage reduces to lower than the braking stop voltage
(set in P0-01). The start braking rate (set in P0-02) of the braking unit can also be set to
adjust the discharge rate during braking so as to change the braking time.

Inovance MDBUN Series Braking Unit User Manual
2.4 Load Curve Diagram
Figure 2-4 Load curve diagram of the MDBUN braking unit
110 100 1000 10000
36
54
72
90
108
126
Max. braking current (A)
MDBUN-45-X
MDBUN-60-X
MDBUN-90-X
Continuous braking time (s)
110 100 1000 10000
36
54
72
90
108
126
Max. braking current (A)
MDBUN-45-X
MDBUN-60-X
MDBUN-90-X
Continuous braking time (s)
Note
In the preceding figure, "X" indicates the voltage class S, T, or 5T. The preceding figure shows that the
MDBUN series braking unit can perform continuous braking at the maximum braking
unit.

Inovance MDBUN Series Braking Unit User Manual
Page 7 of 24
Chapter 3 Mechanical and Electrical Installation
3.1 Mechanical Installation
3.1.1 Installation Environment
1. Ensure that the ambient temperature and humidity meet the requirements in the
following table. Install the braking unit in an environment free from vibration and direct
sunlight.
2. Install the braking unit and external braking resistor on the surface of incombustible
objects with sufficient room for heat dissipation.
3. Ensure that the installation environment is free from corrosive, combustible, and
explosive gas.
4. Ensure that installation environment is free from dust and metal powder.
Item
Requirement
Altitude
Lower than 1000 m (1% de-rated for each 100 m above
this height; max. 4000 m)
Ambient temperature
–10C to +40C
Humidity
Lower than 95% RH, without condensing
Vibration
Lower than 5.9 m/s2(0.6 g)
Storage temperature
–20C to +60C
Pollution level
Level 2
Cooling method
Air cooling
Ingress level
IP20
3.1.2 Overall Dimensions and Installation Clearance Requirements
Figure 3-1 Overall dimensions of the MDBUN series braking unit
Φ5
60 mm
236 mm
247 mm
165 mm
224 mm
110 mm

Inovance MDBUN Series Braking Unit User Manual
Figure 3-2 Installation clearances of the MDBUN series braking unit
Installed vertically upward
10 cm
5 cm MDBUN
Hot air
Cold air
10 cm
5 cm
3.1.3 Mechanical Installation Suggestions
Install the braking resistor in a space with good ventilation, because the braking resistor
gets heated when consuming the feedback energy generated during braking.
Install the braking unit upright to facilitate heat dissipation. Do not lay it upside-down or
horizontally.
If multiple braking units are connected to the drive, install them side by side. If one row of
braking units needs to be installed above another row, install an insulation guide plate to
prevent braking units in the lower row to bake those in the upper row.
Ensure that the distance between the braking unit, drive, and other electric device meets
the requirements shown in Figure 3-2.
3.2 Electrical Installation
The following figure shows the terminal arrangement of the braking unit.
Figure 3-3 Terminal arrangement of the braking unit
12
3
T/A T/B T/C DI DO 24V CO
M
Power wiring
terminal
Control signal
terminal
Mechanical
installation hole
Mechanical
installation hole
Remove the
two screws. Lift the cover upward.
Remove the
cover.
3.2.1 Terminal Description
Description of Power Wiring Terminals
Terminal
Name
Description
+, –
Positive and
negative terminals
of the DC bus
Used as the input point of the
common DC bus

Inovance MDBUN Series Braking Unit User Manual
Page 9 of 24
Terminal
Name
Description
P(+), BR
Terminals for
connecting the
braking resistor
Used for connecting the
braking resistor
Grounding
terminal
Used for grounding
The wiring precautions are as follows:
1. Do not reverse the polarity of the DC bus terminals (+) and (-). Otherwise, the drive and
braking unit may be damaged.
2. The grounding terminal and the power zero line terminal N must be different
terminals.
3. The terminal PE must be grounded reliably, and the resistance value of the
grounding wire must be smaller than 4 Ω.
4. The cable between the braking unit and the drive must not longer than 5 m and must be
twisted-pair, and cable between the braking unit and the braking resistor must not longer
than 10 m.
Description of Control Terminals
The following table describes functions of the control terminals.
Terminal
Name
Description
DI
Digital input
In master mode: block input in the case of an
external fault
In slave mode: start or stop input of braking unit
DO
Digital output
Running/Stop signal output
TA/TB/TC
Fault relay output
Normally open (NO)/Normally closed (NC) contact,
which acts when the braking unit becomes faulty
24V and COM
Power supply/Common
terminal
I/O auxiliary power supply and reference ground
The following figure shows the internal equivalent circuit of the control terminals.
Figure 3-4 Internal equivalent circuit of the control terminals
Logic processing
circuit
COM
Internal equivalent
circuit of the control
board in the braking unit
0V
DI
DO1
External
signal wiring
Auxiliary
power supply
24V 24V+
T/A
T/B
T/C
The descriptions of the preceding figure are as follows:
1. Master braking unit
DI is used as block input. The master stops working and blocks the output when DI is valid.

Inovance MDBUN Series Braking Unit User Manual
DO is sent as the running/stop signal to the slave. When the master starts braking, DO is
valid; when the master stops braking, DO is cancelled.
2. Slave braking unit
DI is used as start/stop signal input. The slave starts braking when DI is valid and stops
braking when DI is cancelled. When the slave starts braking, DO is valid; when the slave
stops braking, DO is cancelled.
3. TA/TB/ TC
TA and TB are in NC contact, and TA and TC are in NO contact. The three terminals are
used as fault output.
Note that the TA, TB, and TC terminals use the following relay contact specifications. Pay
attention to the control power of the control coil in the main circuit contactor.
NC: 3 A, 250 VAC/1 A, 30 VDC
NO: 5 A, 250 VAC/3 A, 30 VDC
3.2.2 Wiring of the Braking Unit
1. Standard wiring method 1
Figure 3-5 Standard wiring method 1
P
MDBUN
braking
unit
－
＋
P(+)
BR Braking
resistor
Contactor
TB TA TC TB TA TC
A2
A1
Circuit
breaker Inovance
M
Drive
Power
supply
S
R
T
V
U
W
N
N
R
S
T
KM1
FU1
KM1
SA1
start
button
SA2
emergency
stop button
In the preceding wiring method, TA/TB/TC on the drive side are used as relay fault output
of the drive, and TA/TB/TC on the braking unit side are used as relay fault output of the
braking unit.
The input voltage class of the contactor control coil is 220 VAC.
2. Standard wiring method 2

Inovance MDBUN Series Braking Unit User Manual
Page 11 of 24
Figure 3-6 Standard wiring method 2
P
MDBUN
braking unit
－
＋
P(+)
BR
Braking
resistor
DIx
COM
TB TA TC
Circuit
breaker Inovance
M
Drive
Power
supply S
R
T
V
U
W
N
R
S
T
If the preceding wiring method is used, you need to allocate a certain DI (for example, DI1)
of the drive with the function of external fault NO input. Take Inovance IS300 servo drive
as an example; to allocate DI3 with the function of external fault NO input, set F4-02 to 11.
When you use the drive of other companies, perform the setting according to the user
manual of this drive.
3. Standard wiring method 3
Figure 3-7 Standard wiring method 3
P
Contactor
TB TA TC
A2
A1
Circuit
breaker Inovance
M
Drive
Power
supply
S
R
T
V
U
W
N
N
R
S
T
KM1
FU1
KM1
SA1
start button
SA2
emergency
stop button
TA
TC
－
＋
Braking unit 1
(P0-03 = 0, master)
－
＋
DO COM
COMDI
Braking unit 2
(P0-03 = 1, slave)
TB
TA
TC
TB
The preceding wiring method is used when multiple braking units are connected in parallel.
The wiring between the braking unit and the braking resistor is not shown in the figure.
The input voltage class of the contactor control coil is 220 VAC.
When multiple braking units are connected in parallel, set one braking unit as the master
(P0-03 = 0), and set all other braking units as the slave (P0-03 = 1).
Set the same braking start voltage (P0-00), braking stop voltage (P0-01), and start braking
rate (P0-02) for the master and all slaves.

Inovance MDBUN Series Braking Unit User Manual
Chapter 4 Operation and Display
4.1 Front Panel
Figure 4-1 Front panel of the braking unit
PWR
RUN
ERR
PWR: power indicator. It is ON after the braking unit is energized.
RUN: running indicator. It is ON when the braking unit is in running state.
ERR: fault indicator. It is ON when the braking unit becomes faulty.
Note
1. You can check whether the braking unit is faulty by viewing the status of the ERR indicator or
observing whether the TA-TB or TA-TC terminal acts.
2. The braking unit can store records of the latest four faults. You can view the records by reading the P2
function code group.
4.2 Operation Panel
An external operation panel is optional for the braking unit for setting the parameters. The
following figure shows the wiring between the external operation panel and the braking
unit.
Figure 4-2 Wiring between the external operation panel and the braking unit
Operation
panel
RJ45 cable
MDBUN braking unit
You can modify the braking unit parameters and monitor the working status of the braking
unit by using the operating panel. The following figure shows the appearance and function
areas of the operation panel.

Inovance MDBUN Series Braking Unit User Manual
Page 13 of 24
Figure 4-3 Diagram of the operation panel
MF.K
RUN STOP
RES
QUICK
PRG ENTER
RUN LOCAL/REMOT FED/REV TUNE/TC
RPM %
A VHz
Master/Slave
indicator Reserved
Running
indicator
Digital display
Programming
key
Reserved
Reserved
Reserved
Reset key
Shift key
Increment key
Decrement key
Confirm key
Unit indicator
Fault indicator
Unit Indicators
Hz A V
RPM %
: Unit indicators, used for displaying the current data unit.
means that the indicator is off, and means that the indicator is on.
Hz A V
RPM %
Hz: unit of frequency
Hz A V
RPM %
A: unit of current
Hz A V
RPM %
V: unit of voltage
Hz A V
RPM %
RPM: unit of rotation speed
Hz A V
RPM %
%: percentage
Running Indicator
This indicator is on when the braking unit is in running state.
Master/Slave indicator
ON indicates that the braking unit is in slave mode, and OFF indicates that the braking unit
is in ON state.
Digital Display
The 5-digit LED display is able to display the bus voltage, maximum continuous braking
current, IGB module base plate temperature, present braking rate, and fault code.
Keys on the Operation Panel
Key
Name
Function
PRG
Programming key
Enter or exit Level I menu.
ENTER
Confirm key
Enter the menu interfaces level by level, and confirm the
parameter setting.
Increment key
Increase data or function code.
Decrement key
Decrease data or function code.
Shift key
Select the displayed parameters in turn in the stop or running
state, and select the digit to be modified when modifying
parameters.
RUN
Reserved
-

Inovance MDBUN Series Braking Unit User Manual
STOP
RES
Reset key
Reset the braking unit after a fault occurs.
MF.K
Reserved
-
QUICK
Reserved
-
4.3 Viewing and Modifying Function Codes
The operation panel of the MDBUN series braking unit adopts three-level menu.
The three-level menu consists of function code group (Level I), function code (Level II),
and function code setting value (level III), as shown in the following figure.
Figure 4-4 Operation procedure on the operation panel
P0
P0-00
730
(Select the function
code group)
(Select the
function code)
(Set the value of
the function code)
Level-I menu
Level-II menu
Level-III menu
PRG
PRG ENTER
ENTER
548
ENTER
Status parameter
PRG
P0-01
ENTER
PRG
(default display) If there is a blinking digit, press
/ / to modify the digit.
You can return to Level II from Level III by pressing PRG or ENTER key.
After you press the ENTER key, the system saves parameter setting first, and then
goes back to Level II and shifts to the next function code.
After you press the PRG key, the system does not save parameter setting, but
directly returns to Level II and keeps staying at the current function code.
In Level III menu, if the parameter has no blinking digit, it means that the parameter
cannot be modified. This may be because:
Such function code is only readable, such as actually detected parameter and
running record parameter.
Such function code cannot be modified in the running state and can only be changed
at stop.
4.4 Setting Function Codes at First Power-On
At the first-use, reliably connect the braking unit, drive, and braking resistor, and power on
the drive. Then, the braking unit is energized, and you can set parameters in function code
group P0 on the operation panel according to the table in section 4.5.
After the parameters in function code group F0 are set, the braking unit starts working in
the preset working mode based on the bus voltage of the drive, and you need not operate
the operation panel, that is, pressing
RUN
or
STOP
RES
.
After the parameter setting is completed, the braking unit can work properly even if the
operation panel is removed.

Inovance MDBUN Series Braking Unit User Manual
Page 15 of 24
4.5 Viewing Status Parameters
When the braking unit is in stop or running state, you can press to display status
parameters in turn.
When the braking unit is in stop or running state, you can view the values of five status
parameters including the bus voltage, output current, present braking rate, and IGBT
module temperature, and fault code. You can press to view the parameter values in
turn, and pay attention to the state of the unit indicators when each parameter value is
displayed.
If the drive is powered off and then powered on, the bus voltage value is displayed by
default.

Inovance MDBUN Series Braking Unit User Manual
Chapter 5 Function Code Table
The symbols in the function code table are described as follows:
"☆": The parameter can be modified when the drive is in either stop or running state.
"★": The parameter cannot be modified when the drive is in the running state.
"●": The parameter is the actually measured value and cannot be modified.
Function
Code
Parameter
Name
Setting
Range
Parameter
Description
Min.
Unit
Default
Property
Group F0
P0-00
Braking
start
voltage
Voltage class:
1) 220 V: P0-01
to 390.0 V
2) 380 V: P0-01
to 730.0 V
3) 480 V: P0-01
to 820.0 V
The braking unit
starts braking
when the bus
voltage is higher
than the value.
0.1 V
Voltage
class:
1) 220 V:
350.0 V
2) 380 V:
670.0 V
3) 480 V:
760.0 V
☆
P0-01
Braking
stop
voltage
Voltage class:
1) 220 V: 320 V
to P0-00
2) 380 V: 620 V
to P0-00
3) 480 V: 700 V
to P0-00
The braking unit
stops braking
when the bus
voltage is lower
than the value.
0.1 V
Voltage
class:
1) 220 V:
340.0 V
2) 380 V:
650.0 V
3) 480 V:
730.0 V
☆
P0-02
Start
braking
rate
1%–100%
This parameter
specifies the
duty ratio when
the bus voltage
is equal to the
value of P0-00.
1%
100
☆
P0-03
Master/Sla
ve mode
selection
0: Master
1: Slave
This parameter
specifies
whether the
working mode of
the braking unit
is master or
slave.
1
0
☆
P0-04
Reserved
-
-
-
-
-
P0-05
Reserved
-
-
-
-
-
P0-06
Restore
default
setting
0: Not restore
1: Only restore
group P0
2: Clear all
information of
group P2
-
1
0
★
Group P2
P2-00
Software
version
-
-
-
-
●

Inovance MDBUN Series Braking Unit User Manual
Page 17 of 24
P2-01
Types of
latest four
faults
-
This parameter
specifies the latest
four fault types.
The digit in the unit's
place is the type of
the latest fault, and
the digit in the ten's
place is the type of
the latest second
fault, by analogy.
-
-
●
P2-02
Bus
voltage
upon fault
-
This parameter
specifies the bus
voltage when the
latest fault occurs.
-
-
●
P2-03
Current
upon fault
-
This parameter
specifies the current
when the latest fault
occurs.
-
-
●
P2-04
Braking
rate upon
fault
-
This parameter
specifies the braking
rate (duty ratio) when
the latest fault occurs.
-
-
●
P2-05
Module
temperatu
re upon
fault
-
This parameter
specifies the module
temperature when the
latest fault occurs.
-
-
●
P2-06
Braking
unit status
upon fault
-
This parameter
specifies the status of
the braking unit when
the latest fault occurs.
bit0: DI
bit1: DO
bit2: fan
bit3: relay
bit4: braking
bit5: power-on
detection
bit6: current sampling
detection
bit7: bus voltage
setup
-
-
●
P2-07
Running
time
before
fault
-
This parameter
specifies the running
time (in unit of
seconds) when the
latest fault occurs.
The time is measured
starting from this
power-on, and is
cleared in the case of
power-on again or
fault.
-
-
●
P2-08
Accumulat
ive
braking
time
-
This parameter
specifies the
accumulative braking
time, in unit of
-
-
●

Inovance MDBUN Series Braking Unit User Manual
seconds.
P2-09
Accumulat
ive
power-on
time
-
This parameter
specifies the
accumulative
power-on time, in unit
of hours.
-
-
●
P2-10
Braking
unit use
ratio
-
The value is equal to
P2-08 divided by
P2-09, in unit of
percentage.
-
-
●

Inovance MDBUN Series Braking Unit User Manual
Page 19 of 24
Chapter 6 Troubleshooting
The MDBUN series braking unit provides nine pieces of alarm information and protection
function. After a fault occurs, the protection function is implemented, and the braking unit
stops working and displays the fault code on the operation panel (if the operation panel is
available).
If a fault occurs during running or commissioning, you can determine the fault type,
analyze the causes, and perform troubleshooting according to the following table before
contacting Inovance.
If you do not know how to perform troubleshooting during commissioning, contact
technical support engineers of Inovance.
Fault
Code
Description
Possible Causes
Troubleshooting
ERR01
Hardware
overcurrent
1. The external circuit is
short-circuited.
2. The feedback energy
changes suddenly or becomes
abnormal.
3. The power of the braking unit
is too small.
4. The resistance of the braking
resistor is too small.
1. Check whether the external circuit is
short-circuited or abnormal. If yes, press
STOP
RES
or power on the braking unit
again.
2. Reduce sudden change of the
feedback energy.
3. Select a braking unit of higher power.
4. Select a proper braking resistor.
5. Contact technical support engineers
of Inovance.
ERR02
Software
overcurrent
ERR03
Overvoltage
1. The input voltage class of
the adaptable drive is
incorrectly set.
2. The feedback energy
becomes abnormal.
3. The braking unit has
insufficient capacity.
1. Correctly set the input voltage class of
the adaptable drive.
2. Check the input feedback energy.
3. Select a braking unit of higher power.
4. Contact technical support engineers
of Inovance.
ERR04
Overheat
1. The air filter is blocked or the
fan is damaged.
2. The power cable of the fan is
not securely inserted or is
damaged.
3. The ambient temperature is
too high.
4. The power of the braking unit
is too small.
1. Clear the air filter or replace the fan.
2. Check that the power cable of the fan
is securely inserted and is normal.
3. Reduce the ambient temperature.
4. Contact technical support engineers
of Inovance.
ERR05
Braking
resistor
short-circuit
1. The braking resistor or the
wiring of the braking resistor is
short-circuited.
1. Check that the braking resistor and
the wiring are normal.
2. Contact technical support engineers
of Inovance.
ERR06
Braking
resistor
open-circuit
protection
1. No braking resistor is
connected or the braking
resistor is burnt out.
2. The IGBT is burnt out.
1. Check that the braking resistor is
normal and connected properly.
2. Check that the IGBT is normal.
3. Contact technical support engineers
of Inovance.
ERR07
Reserved
Reserved
Reserved
ERR08
IGBT direct
break-over
The IGBT module is damaged
1. Replace the braking unit.
2. Contact technical support engineers
of Inovance.
ERR09
Reference
source fault
The reference source for
analog sampling is faulty.
1. Replace the braking unit.
2. Contact technical support engineers
of Inovance.

Inovance MDBUN Series Braking Unit User Manual
Chapter 7 Selection of Braking Unit and Braking Resistor
7.1 Selection of Braking Unit
Select the braking unit by following two rules:
1. Select the braking unit of a proper input voltage class based on the input voltage class
of the drive.
2. Select the braking unit of proper power based on the braking power required by braking
of the drive.
Ensure that the power of the braking unit is larger than the braking power. If the braking
power is not known, estimate it according to the formula: Pb = P x Td x K.
In the formula:
Pb: braking power
P: motor power
K: mechanical energy conversion efficiency; generally, k = 0.7
Td: ration of braking torque to rated motor torque
Application
Elevator, hoist,
crane
Winding and
unwinding
equipment
Large-inertia
equipment that
requires quick
stop
Common-inertia
equipment
Td
100%
120%
120%
80%
7.2 Selection of Braking Resistor
7.2.1 Calculating the Resistance
During braking, almost all regenerative energy of the motor is consumed by the braking
resistor.
According to the formula U x U/R = Pb:
U refers to the braking voltage at system stable braking.
The value of U varies with different systems:
220 VAC system: U = 380 V
380 VAC system: U = 700 V
480 VAC system: U = 800 V
If the calculated value of R is smaller than the minimum resistance under each voltage
class, multiple braking units need to be used.
7.2.2 Calculating Power of Braking Resistor
In theory, the power of the braking resistor is consistent with the braking power.
Considering de-rating use to 70%, you can calculate the power of the braking resistor
according to the formula 0.7 x Pr = Pb x ED.
Pr: power of the braking resistor
ED: braking frequency, that is, percentage of the regenerative process to the whole
working process